Open rate has been the headline metric of email marketing for two decades. It has never been less reliable than it is right now. Most email marketers still check it first, treat it as a signal of campaign health, and make decisions based on it. In most cases, it is telling them almost nothing useful.This is not a niche opinion anymore. The case against open rate as a primary metric has been building for years, and it has gotten harder to ignore. When I dug deeper into our own sending data at AutoSend and talked to customers running campaigns at scale, the pattern was consistent: the teams obsessing over open rates were making worse decisions than the ones ignoring it entirely.Here is why.<h3>The number is broken before you even read it</h3>Open rate works by embedding a tiny invisible image into every email you send. When a recipient opens the email and their client loads images, that pixel fires and logs an open. Seems straightforward. The problem is that almost every major inbox provider now interferes with this in some way.Apple Mail Privacy Protection, which rolled out in 2021, preloads all images through Apple's proxy servers before the user does anything. Every Apple Mail user on your list registers as an open automatically, whether or not they ever saw your email. Depending on your list composition, that could be 30 to 50 percent of your recipients registering as "opened" before a single human eyeball touched the email.Gmail caches images on its own servers, stripping out timestamp and device data in the process. You see an open. You do not know when, or from where, or if it was a real person at all, because email security scanners and bots routinely trigger pixels during automated scanning too.The number in your open rate dashboard is a cocktail of real opens, bot activity, Apple pre-fetches, Gmail caching, and blocked loads. It is not a metric. It is noise with a percentage sign attached.<h3>It is also quietly hurting your deliverability</h3>This is the part that does not get talked about enough. Open tracking does not just give you bad data. It can actively make your emails harder to deliver.Gmail and Outlook have gotten very good at identifying promotional and marketing emails. One of their clearest signals is the presence of a tracking pixel pointing to a third-party domain. It is exactly what spammers use. When your email arrives with a hidden image calling out to an external server, providers treat it with suspicion. Sometimes that means the spam folder. Sometimes that means a banner that reads "This message might be suspicious." Either way, your email is starting at a disadvantage before the recipient has a chance to engage.This is consistent with what we have observed across AutoSend customers too. When open tracking is disabled, deliverability improves. It is not a guaranteed fix for everything, but it is a meaningful variable.<h3>Optimizing for it makes your decisions worse</h3>Even if the data were accurate, open rate is the wrong thing to optimize for. It measures whether someone's email client loaded an image. That is not engagement. That is not intent. That is not conversion.The downstream effects of treating it like a real metric are subtle but compounding. You A/B test subject lines based on open rate and end up optimizing for curiosity rather than relevance. You conclude your list is healthy because opens look strong, while replies and clicks quietly tell a different story. You keep sending to people who technically "opened" your emails but never once acted on anything, gradually wearing down your sender reputation with an audience that is not actually interested.A high open rate can mask a broken campaign for a surprisingly long time.<h3>What to look at instead</h3>Click-through rate is a real signal. Someone read enough to click, then decided to act. No proxy server fakes that.Reply rate is better still, especially for campaigns where you are trying to start a conversation. A reply means someone read your email, had a reaction, and responded. That is about as high-intent as email engagement gets.For transactional or product-driven email, track completions. Did the user verify their account? Did they follow through on the action your email prompted? That is your metric.None of these numbers are as satisfying to look at as a big open rate percentage. But they reflect what is actually happening, and decisions made on them hold up.<h3>The practical change</h3>If you are using AutoSend, open tracking is off by default, so you are already starting in the right place. If you are on another platform, go into your settings and turn it off before your next send. Most tools have it enabled by default, so you will need to actively look for it. Then set up click tracking if you have not already, and define one primary metric for the campaign before you send it. Not after. Decide upfront whether success means a click, a reply, or a conversion, and measure against that.Give it two or three campaigns. Compare your spam complaint rate and click rate against previous sends. The open rate number will disappear from your dashboard, and you will likely find you do not miss it.

Open rate has been the headline metric of email marketing for two decades. It has never been less reliable than it is right now. Most email marketers still check it first, treat it as a signal of campaign health, and make decisions based on it. In most cases, it is telling them almost nothing useful.This is not a niche opinion anymore. The case against open rate as a primary metric has been building for years, and it has gotten harder to ignore. When I dug deeper into our own sending data at AutoSend and talked to customers running campaigns at scale, the pattern was consistent: the teams obsessing over open rates were making worse decisions than the ones ignoring it entirely.Here is why.The number is broken before you even read itOpen rate works by embedding a tiny invisible image into every email you send. When a recipient opens the email and their client loads images, that pixel fires and logs an open. Seems straightforward. The problem is that almost every major inbox provider now interferes with this in some way.Apple Mail Privacy Protection, which rolled out in 2021, preloads all images through Apple's proxy servers before the user does anything. Every Apple Mail user on your list registers as an open automatically, whether or not they ever saw your email. Depending on your list composition, that could be 30 to 50 percent of your recipients registering as "opened" before a single human eyeball touched the email.Gmail caches images on its own servers, stripping out timestamp and device data in the process. You see an open. You do not know when, or from where, or if it was a real person at all, because email security scanners and bots routinely trigger pixels during automated scanning too.The number in your open rate dashboard is a cocktail of real opens, bot activity, Apple pre-fetches, Gmail caching, and blocked loads. It is not a metric. It is noise with a percentage sign attached.It is also quietly hurting your deliverabilityThis is the part that does not get talked about enough. Open tracking does not just give you bad data. It can actively make your emails harder to deliver.Gmail and Outlook have gotten very good at identifying promotional and marketing emails. One of their clearest signals is the presence of a tracking pixel pointing to a third-party domain. It is exactly what spammers use. When your email arrives with a hidden image calling out to an external server, providers treat it with suspicion. Sometimes that means the spam folder. Sometimes that means a banner that reads "This message might be suspicious." Either way, your email is starting at a disadvantage before the recipient has a chance to engage.This is consistent with what we have observed across AutoSend customers too. When open tracking is disabled, deliverability improves. It is not a guaranteed fix for everything, but it is a meaningful variable.Optimizing for it makes your decisions worseEven if the data were accurate, open rate is the wrong thing to optimize for. It measures whether someone's email client loaded an image. That is not engagement. That is not intent. That is not conversion.The downstream effects of treating it like a real metric are subtle but compounding. You A/B test subject lines based on open rate and end up optimizing for curiosity rather than relevance. You conclude your list is healthy because opens look strong, while replies and clicks quietly tell a different story. You keep sending to people who technically "opened" your emails but never once acted on anything, gradually wearing down your sender reputation with an audience that is not actually interested.A high open rate can mask a broken campaign for a surprisingly long time.What to look at insteadClick-through rate is a real signal. Someone read enough to click, then decided to act. No proxy server fakes that.Reply rate is better still, especially for campaigns where you are trying to start a conversation. A reply means someone read your email, had a reaction, and responded. That is about as high-intent as email engagement gets.For transactional or product-driven email, track completions. Did the user verify their account? Did they follow through on the action your email prompted? That is your metric.None of these numbers are as satisfying to look at as a big open rate percentage. But they reflect what is actually happening, and decisions made on them hold up.The practical changeIf you are using AutoSend, open tracking is off by default, so you are already starting in the right place. If you are on another platform, go into your settings and turn it off before your next send. Most tools have it enabled by default, so you will need to actively look for it. Then set up click tracking if you have not already, and define one primary metric for the campaign before you send it. Not after. Decide upfront whether success means a click, a reply, or a conversion, and measure against that.Give it two or three campaigns. Compare your spam complaint rate and click rate against previous sends. The open rate number will disappear from your dashboard, and you will likely find you do not miss it.

Tracking open rates could be sending your emails to spam. Learn why the metric is unreliable and what to measure instead.

Stop Tracking Open Rates. Your Deliverability Will Thank You.

If your emails are landing in spam, chances are your domain authentication isn't set up correctly. SPF, DKIM, and DMARC are the three pillars of email authentication, and getting them right is the single most impactful thing you can do for your email deliverability.Why Email Authentication MattersEvery time you send an email, the receiving server (Gmail, Outlook, Yahoo, etc.) asks three questions:Is this server allowed to send emails for this domain? (SPF)Was this email actually sent by who it claims to be from? (DKIM)What should I do if authentication fails? (DMARC)If you can't answer these questions convincingly, your emails are treated as suspicious. That means spam folder, or worse, outright rejection.Think of it like showing up at a building entrance. SPF is the guest list. DKIM is your ID badge. DMARC is the security policy that tells the guard what to do when someone doesn't have proper credentials.Part 1: SPF (Sender Policy Framework)What SPF DoesSPF lets you publish a list of servers that are authorized to send emails on behalf of your domain. When a receiving server gets an email claiming to be from yourdomain.com, it checks your SPF record to see if the sending server is on the list.How to Set Up SPFSPF is a TXT record added to your domain's DNS. Here's the basic structure:v=spf1 include:amazonses.com ~all
Breaking this down:v=spf1 tells the server this is an SPF recordinclude:amazonses.com authorizes Amazon SES servers (which AutoSend uses) to send on your behalf~all tells receiving servers to treat any other sender as suspicious (soft fail)If you're sending from a subdomain (e.g., mail.yourdomain.com), add the SPF record to that specific subdomain, not the root domain.If you also use another email provider (like Google Workspace for internal email), your root domain SPF might look like:v=spf1 include:_spf.google.com include:amazonses.com ~all
SPF Qualifier ReferenceThe qualifier at the end of your SPF record controls what happens to emails from unauthorized servers:QualifierMeaningRecommendation+allAllow everyoneNever use this. It completely defeats the purpose of SPF.?allNeutralEssentially useless. Provides no protection.~allSoft failGood default. Flags unauthorized senders as suspicious.-allHard failStrongest option. Use once you're confident your setup is correct.Start with ~all and move to -all after a few weeks of confirmed clean delivery.Common SPF MistakesMistake 1: Multiple SPF records on the same domainThis is probably the most common SPF mistake, and it's a silent killer. If your domain has two TXT records that both start with v=spf1, SPF will return a permerror and fail completely. That's worse than having no SPF at all.Wrong:v=spf1 include:amazonses.com ~all
v=spf1 include:_spf.google.com ~all
Correct:v=spf1 include:amazonses.com include:_spf.google.com ~all
Merge all your authorized senders into a single SPF record.Mistake 2: Exceeding the 10 DNS lookup limitSPF has a hard limit of 10 DNS lookups. Every include: triggers one or more lookups, and nested includes count too. If you exceed 10, SPF returns permerror and fails.For example, include:_spf.google.com alone uses up 3-4 lookups because Google's SPF record includes further nested records.How to check: Use a tool like MXToolbox SPF Lookup to see your total lookup count.How to fix: If you're close to the limit, consider using ip4: or ip6: mechanisms for services with static IPs, as these don't count toward the lookup limit.Mistake 3: Using +allThis authorizes every server on the internet to send email from your domain. It's the equivalent of leaving your front door wide open with a sign that says "come on in." Inbox providers like Gmail view +all as a negative reputation signal.Mistake 4: Including unnecessary domainsEvery include: costs you a DNS lookup (and you only have 10). Don't include your root domain's SPF in your subdomain's SPF record unless the subdomain actually needs those same servers authorized.For example, if you send marketing emails from mail.yourdomain.com through AutoSend, the SPF for that subdomain only needs:v=spf1 include:amazonses.com ~all
Don't add include:yourdomain.com just because it exists. That pulls in all the root domain's authorized senders, which is unnecessary and wastes lookups.Mistake 5: Forgetting subdomain SPFSPF records don't cascade down to subdomains. If you have SPF on yourdomain.com but send emails from mail.yourdomain.com, you need a separate SPF record on the subdomain. The root domain's SPF won't cover it.Part 2: DKIM (DomainKeys Identified Mail)What DKIM DoesDKIM adds a cryptographic signature to every outgoing email. The receiving server uses a public key published in your DNS to verify that the email wasn't tampered with in transit and that it genuinely came from your domain.Think of it as a wax seal on a letter. If the seal is intact, you know the letter hasn't been opened or modified since it was sent.How to Set Up DKIMDKIM setup involves two parts:The private key stays on the sending server (AutoSend handles this for you). It's used to sign every outgoing email.The public key gets published in your DNS as a TXT or CNAME record so receiving servers can verify the signature.Option A: CNAME record (recommended for AutoSend)Type: CNAME
Name: autosend._domainkey
Content: autosend._domainkey.yourdomain.com.d.autosend.email
The CNAME approach is preferred because if we ever rotate keys, the update happens on our end automatically. You don't have to touch your DNS.Option B: TXT record (manual key)Type: TXT
Name: autosend._domainkey
Content: v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GN...
If you go with a TXT record, make sure you include the full record with v=DKIM1; k=rsa; before the p= value. Just pasting the raw key starting with p= can cause verification failures with some email providers.Common DKIM MistakesMistake 1: Missing the v=DKIM1 tagA proper DKIM TXT record should start with v=DKIM1; k=rsa; before the public key. While technically optional per the spec, some receiving servers are strict about this. Missing it can cause intermittent DKIM failures that are hard to debug.Wrong:p=MIGfMA0GCSqGSIb3DQEBAQUAA4GN...
Correct:v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GN...
Mistake 2: Using a TXT record when you should use CNAMEIf your email provider (like AutoSend) gives you a CNAME to add, use the CNAME. Don't copy the public key and paste it as a TXT record. The CNAME approach means key rotations are handled automatically. With a TXT record, if the signing key changes on the provider's end, your DNS still has the old key, and every email will fail DKIM silently.Mistake 3: Truncated key in DNSSome DNS providers have character limits on TXT records. If your DKIM public key gets cut off, DKIM verification will fail every time. After adding the record, always verify it using a tool like MXToolbox DKIM Lookup to make sure the full key is present.Mistake 4: DKIM alignment failureDKIM can pass verification but still fail DMARC alignment. This happens when the d= domain in the DKIM signature doesn't match (or isn't a subdomain of) the From address domain. For example, if your From address is you@mail.yourdomain.com but DKIM signs with d=yourdomain.com, that's fine in relaxed alignment mode. But if DKIM signs with d=senderprovider.com, alignment fails even though the signature itself is valid.Part 3: DMARC (Domain-based Message Authentication, Reporting &amp; Conformance)What DMARC DoesDMARC ties SPF and DKIM together and tells receiving servers what to do when authentication fails. It also gives you reporting so you can see who's sending email from your domain and whether authentication is passing or failing.Without DMARC, even if SPF and DKIM fail, the receiving server has no guidance on what to do. DMARC is the policy layer that makes everything actionable.How DMARC Lookup WorksThis is important to understand. When a receiving server gets an email from user@mail.yourdomain.com, it checks for DMARC in this order:_dmarc.mail.yourdomain.com (exact match on the sending subdomain)_dmarc.yourdomain.com (fallback to the organizational/root domain)If it finds a record at step 1, it uses that. If not, it falls back to step 2. This means a single DMARC record at the root domain covers all subdomains automatically. You don't need to add DMARC to every subdomain unless you want different policies for different subdomains.How to Set Up DMARCAdd a TXT record to your root domain:Type: TXT
Name: _dmarc
Content: v=DMARC1; p=quarantine; sp=quarantine; rua=mailto:dmarc@yourdomain.com; pct=100; adkim=r; aspf=r;
Breaking this down:TagMeaningRecommended Valuev=DMARC1Protocol versionAlways DMARC1p=Policy for root domainStart with quarantine, move to rejectsp=Policy for subdomainsStart with quarantine, move to rejectrua=Where to send aggregate reportsAn email address you monitorpct=Percentage of emails the policy applies to100 (apply to all)adkim=DKIM alignment moder (relaxed) allows subdomain matchingaspf=SPF alignment moder (relaxed) allows subdomain matchingThe DMARC Policy ProgressionDon't jump straight to p=reject. Follow this progression:Week 1-2: Monitor modev=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com;
This doesn't affect delivery but starts sending you reports. Use this time to identify all legitimate email sources and make sure SPF/DKIM are passing.Week 3-4: Quarantine modev=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com; pct=100;
Failed emails go to spam. Monitor reports to make sure nothing legitimate is getting caught.Week 5+: Reject modev=DMARC1; p=reject; rua=mailto:dmarc@yourdomain.com; pct=100;
Failed emails are outright rejected. This is the strongest protection and gives the best deliverability signal to inbox providers.The sp= Tag for Subdomain ControlThe sp= tag lets you set a different policy for subdomains than the root domain. This is useful during transition:v=DMARC1; p=reject; sp=quarantine; rua=mailto:dmarc@yourdomain.com;
This rejects failures from the root domain but only quarantines failures from subdomains, giving you a safety net while you're still setting up authentication on newer subdomains.Common DMARC MistakesMistake 1: Staying on p=none foreverThis is the most common mistake we see. p=none is monitoring mode only. It tells receiving servers "don't do anything about authentication failures." It provides zero deliverability benefit. It's meant to be temporary while you get SPF and DKIM sorted out. Staying on p=none is like installing a security camera but telling the guards to never actually stop anyone.Gmail, Yahoo, and other major providers have explicitly stated that a p=none DMARC policy is not sufficient for good deliverability. Move to p=quarantine as soon as your reports show clean results.Mistake 2: No rua= tag (no reporting)Without the rua= tag, you get no DMARC reports. That means you have no visibility into whether authentication is passing or failing, who's sending email from your domain, or whether someone is spoofing you. Always include a rua= tag and actually monitor the reports.Make sure the email address in rua= actually exists and can receive mail. Setting up dmarc@yourdomain.com and never creating the mailbox is a common oversight.Mistake 3: Misunderstanding alignmentDMARC doesn't just check if SPF and DKIM pass. It checks if they pass and align with the From domain. This is a critical distinction.For example:SPF passes for the envelope sender bounce@esp.comDKIM passes with d=esp.comBut the From header says you@yourdomain.comBoth SPF and DKIM passed, but neither aligns with the From domain. DMARC fails.For DMARC to pass, you need at least one of:SPF to pass AND the envelope sender domain to match the From domainDKIM to pass AND the DKIM d= domain to match the From domainWith relaxed alignment (adkim=r; aspf=r;), subdomain matching counts. So DKIM signing with d=mail.yourdomain.com aligns with a From address of you@yourdomain.com.Mistake 4: Adding DMARC to every subdomainYou don't need a separate DMARC record for every subdomain. A single record at _dmarc.yourdomain.com covers all subdomains automatically via the fallback mechanism. Only add subdomain-level DMARC if you need a different policy for a specific subdomain.Putting It All Together: A Complete Setup ChecklistHere's the step-by-step process for a clean email authentication setup:Step 1: Set up SPF on your sending domainIf you're sending through AutoSend from a subdomain:Type: TXT
Name: mail (or whatever your sending subdomain is)
Content: v=spf1 include:amazonses.com ~all
If your root domain also sends email (e.g., through Google Workspace):Type: TXT
Name: @ (root domain)
Content: v=spf1 include:_spf.google.com ~all
Remember: one SPF record per domain/subdomain. Never two.Step 2: Set up DKIMAdd the CNAME or TXT record provided by AutoSend:Type: CNAME
Name: autosend._domainkey
Content: (value provided by AutoSend)
Step 3: Set up DMARC on the root domainType: TXT
Name: _dmarc
Content: v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com; adkim=r; aspf=r;
Step 4: Send a test emailUse Mail Tester or check the raw headers in Gmail. Look for:spf=passdkim=passdmarc=passIf all three show "pass," you're in good shape.Step 5: Monitor DMARC reports for 1-2 weeksCheck your DMARC reports to make sure there are no legitimate emails failing authentication. You can use free tools like DMARC Analyzer to parse the XML reports into something readable.Step 6: Tighten your policiesOnce reports are clean:Upgrade DMARC from p=none to p=quarantineAfter another 2 weeks, upgrade to p=rejectUpgrade SPF from ~all to -allQuick Reference: DNS Records at a GlanceHere's what a properly configured domain looks like in DNS:Root domain (yourdomain.com):TypeNameContentTXT@v=spf1 include:_spf.google.com ~allTXT_dmarcv=DMARC1; p=reject; rua=mailto:dmarc@yourdomain.com;Sending subdomain (mail.yourdomain.com):TypeNameContentTXTmailv=spf1 include:amazonses.com ~allCNAMEautosend._domainkey.mail(AutoSend DKIM value)Clean, minimal, and effective.Need Help?If you're an AutoSend customer and your emails are still landing in spam after following this guide, reach out to us. We'll check your DNS records, review your sending patterns, and help you get to the inbox.

This guide walks you through what each protocol does, how to set them up, and the common mistakes that silently wreck your inbox placement.

The Complete Guide to Email Authentication: SPF, DKIM, and DMARC

You're sending legitimate emails to your customers, but Gmail is showing them a big orange warning: "We can't verify that this email came from the sender so it might not be safe to respond to it."<img class="rounded-2xl border border-primaryBorder mx-auto" src="https://dqy38fnwh4fqs.cloudfront.net/blog/blog-content-image-5cf0637a-7f5d-4b67-839e-e65bf98b9ecc.webp">This sucks. Your emails aren't spam. You're not phishing anyone. But to Gmail and other inbox providers, they look suspicious.If you're using an email service like AutoSend, Amazon SES, SendGrid, Postmark, or Mailgun to send emails, there's a good chance your DNS records are misconfigured. Specifically, something called DMARC alignment.Here's what's actually happening and how to fix it.<h2>What's Really Going On</h2>When your email service sends an email on your behalf, there's a behind-the-scenes address called the Return-Path. This is different from the From address your customers see.For example, when you send an email from <code>hello@yourcompany.com</code>, your email service might use <code>bounces@mail.yourcompany.com</code> as the Return-Path. This is normal. Email services do this to handle bounces and track delivery.The problem happens when you have something called "strict alignment" turned on in your DMARC settings. With strict alignment, these two addresses need to match exactly. But they don't because one uses a subdomain. So Gmail sees the mismatch and freaks out.This is the issue most people hit when using email services. The fix is simple once you know what to look for.<h2>Understanding the Three Email Records</h2>Think of email authentication like a security system with three checks. Each one verifies something different about your email.<h3>SPF: The Authorized Sender List</h3><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/spf-sender-policy-framework">SPF</a> is a list in your DNS that says "these mail servers are allowed to send emails for my domain." When you use an email service to send emails, you need to add them to this list.The most common mistake is using <code>-all</code> at the end of your SPF record instead of <code>~all</code>. The <code>-all</code> means "reject anything not on this list" which is too strict. If your email service isn't properly listed, your emails get rejected. Use <code>~all</code> instead, which means "mark as suspicious" rather than outright rejection.Another mistake is adding your email service to a subdomain but forgetting to add it to your main domain. If you send from <code>hello@yourcompany.com</code>, make sure your main domain's SPF record includes your email service.Example SPF records:If you're using Google Workspace and AutoSend:<pre><code>v=spf1 include:_spf.google.com include:amazonses.com ~all</code></pre>If you're using Google Workspace and SendGrid:<pre><code>v=spf1 include:_spf.google.com include:sendgrid.net ~all</code></pre>If you're using Microsoft 365 and Postmark:<pre><code>v=spf1 include:spf.protection.outlook.com include:spf.mtasv.net ~all</code></pre>The pattern is always: <code>v=spf1</code> followed by domains, ending with <code>~all</code>.<h3>DKIM: The Tamper-Proof Seal</h3><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/dkim-domainkeys-identified-mail">DKIM</a> is a digital signature that proves your email hasn't been modified in transit. Your email service signs the email with a private key, and receivers check it with a public key in your DNS.The issue happens when you have old DKIM keys from a previous email service but no keys from your current one. Or worse, empty DKIM records that say "we sign emails" but don't provide a way to verify them.Make sure you have DKIM keys from your current email service in your DNS. Your email service dashboard will show you what records to add.Example DKIM records:Most email services give you TXT records to add. For AutoSend, you might add:<pre><code>Record name: autosend._domainkey
Record type: TXT
Record value: p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBg...</code></pre>For SendGrid, it might look like:<pre><code>Record name: s1._domainkey.yourcompany.com
Record type: CNAME
Record value: s1.domainkey.u12345.wl.sendgrid.net</code></pre>For Google Workspace, you'll get a TXT record:<pre><code>Record name: google._domainkey.yourcompany.com
Record type: TXT
Record value: v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBA...</code></pre>Your email service will provide the exact values. Just copy them into your DNS.<h3>DMARC: The Policy That Ties It Together</h3><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/dmarc-domain-based-message-authentication-reporting-conformance">DMARC</a> tells email receivers what to do if SPF or DKIM checks fail. But it also does something tricky called "alignment checking."There are two types of alignment: strict and relaxed. Strict alignment means the domains have to match exactly. So <code>hello@yourcompany.com</code> and <code>bounces@mail.yourcompany.com</code> don't match because one uses a subdomain.Relaxed alignment is smarter. It understands that <code>mail.yourcompany.com</code> and <code>yourcompany.com</code> are part of the same organization, so it counts them as matching.Almost every email service uses subdomains for technical stuff like bounces. This is why relaxed alignment is the standard, and why strict alignment breaks things.Example DMARC records:A good starting DMARC record with relaxed alignment:<pre><code>Record name: _dmarc.yourcompany.com
Record type: TXT
Record value: v=DMARC1; p=none; rua=mailto:dmarc@yourcompany.com; adkim=r; aspf=r</code></pre>Once you've verified everything works, change to quarantine:<pre><code>v=DMARC1; p=quarantine; rua=mailto:dmarc@yourcompany.com; adkim=r; aspf=r; pct=100</code></pre>Breaking down what each part means:<ul><li><code>v=DMARC1</code> - DMARC version</li><li><code>p=quarantine</code> - Put suspicious emails in spam (use <code>p=none</code> while testing)</li><li><code>rua=mailto:dmarc@yourcompany.com</code> - Where to send reports</li><li><code>adkim=r</code> - Relaxed DKIM alignment (this is the important one)</li><li><code>aspf=r</code> - Relaxed SPF alignment (also important)</li><li><code>pct=100</code> - Apply policy to 100% of emails</li></ul>The key parts are <code>adkim=r</code> and <code>aspf=r</code>. These need to be set to <code>r</code> (relaxed) not <code>s</code> (strict).<h2>How to Figure Out What's Wrong</h2>First, check your actual DNS records. Don't trust what your DNS service provider's dashboard says. Use a command line tool or an online DNS checker to see what's actually there. Look up your domain's TXT records and your DMARC records.Common things you'll find: multiple DMARC records (you can only have one), strict alignment enabled when it should be relaxed, or your email service missing from your main domain's SPF record.Next, send yourself a test email and look at the raw headers. In Gmail, click the three dots and choose "Show original." Look for the Return-Path and Authentication-Results headers. This will show you exactly what's failing.<img class="rounded-2xl border border-primaryBorder mx-auto" src="https://dqy38fnwh4fqs.cloudfront.net/blog/blog-content-image-723cc788-05ab-49a5-b736-974ae17bb1ff.webp">If you've set up DMARC reports (the <code>rua=</code> part of your DMARC record), you'll get XML reports showing authentication failures. They're ugly to read but they tell you exactly what's going wrong. Just give it to Claude or ChatGPT for interpretation. <h2>The Fix</h2>The fix usually involves three changes.Change your DMARC to relaxed alignment. Find your DMARC record and look for <code>adkim=s; aspf=s</code>. Change both of those to <code>r</code> instead of <code>s</code>. This tells email receivers that subdomains are okay as long as they're part of the same organization.Add your email service to your main domain's SPF record. If you're using AutoSend, add <code>include:amazonses.com</code> to your SPF record. For SendGrid, add <code>include:sendgrid.net</code>. For Postmark, add <code>include:spf.mtasv.net</code>. Your email service's documentation will tell you what to add.Change <code>-all</code> to <code>~all</code> in your SPF record. This changes from "reject" to "mark as suspicious" which is safer and more forgiving if something goes wrong.That's it. No content changes, no IP warming, no deliverability magic. Just three DNS updates and your emails will stop showing warnings.<h2>Quick Checklist</h2>If you're seeing warnings, here's what to check. Is your email service included in your main domain's SPF record? Are you using <code>~all</code> at the end of that record instead of <code>-all</code>? Do you have DKIM keys from your current email service in your DNS? Do you have only one DMARC record with relaxed alignment?Send yourself a test email and check the headers in Gmail (three dots, then Show original). Make sure SPF, DKIM, and DMARC all show as passing.<img class="rounded-2xl border border-primaryBorder mx-auto" src="https://dqy38fnwh4fqs.cloudfront.net/blog/blog-content-image-ef3b7beb-05cd-4e42-a69f-f56ed52c3474.webp"><h2>Why This Matters Now</h2>Email authentication has been around for years, but Gmail and Yahoo made their requirements stricter in 2024. What used to work fine might now trigger warnings.That orange warning banner kills trust. But it's fixable with DNS records. Once you understand what SPF, DKIM, and DMARC actually do, fixing them is straightforward.Think of it this way: SPF says who can send emails for you. DKIM proves the email hasn't been tampered with. DMARC says what to do if those checks fail. Get those three working with relaxed alignment and you're done.<h2>One More Thing</h2>Email authentication shouldn't be this confusing. The problem is that most email services just give you DNS records to copy without explaining what they do or why they matter.If you're stuck on this, check your email service's documentation for their SPF and DKIM setup instructions. Most have a support article that walks through it step by step.And if you're still seeing warnings after making these changes, reach out to your email service's support. They can usually spot the issue in a few minutes since they've seen it hundreds of times before.The key is understanding that strict alignment is what breaks things for most people. Switch to relaxed alignment and make sure your email service is properly authorized in your DNS. That solves it 90% of the time.<hr>Bonus tip: Disable open rate tracking for your emails if you're using a new domain to send emails.

You're sending legitimate emails to your customers, but Gmail is showing them a big orange warning: "We can't verify that this email came from the sender so it might not be safe to respond to it."This sucks. Your emails aren't spam. You're not phishing anyone. But to Gmail and other inbox providers, they look suspicious.If you're using an email service like AutoSend, Amazon SES, SendGrid, Postmark, or Mailgun to send emails, there's a good chance your DNS records are misconfigured. Specifically, something called DMARC alignment.Here's what's actually happening and how to fix it.What's Really Going OnWhen your email service sends an email on your behalf, there's a behind-the-scenes address called the Return-Path. This is different from the From address your customers see.For example, when you send an email from hello@yourcompany.com, your email service might use bounces@mail.yourcompany.com as the Return-Path. This is normal. Email services do this to handle bounces and track delivery.The problem happens when you have something called "strict alignment" turned on in your DMARC settings. With strict alignment, these two addresses need to match exactly. But they don't because one uses a subdomain. So Gmail sees the mismatch and freaks out.This is the issue most people hit when using email services. The fix is simple once you know what to look for.Understanding the Three Email RecordsThink of email authentication like a security system with three checks. Each one verifies something different about your email.SPF: The Authorized Sender ListSPF is a list in your DNS that says "these mail servers are allowed to send emails for my domain." When you use an email service to send emails, you need to add them to this list.The most common mistake is using -all at the end of your SPF record instead of ~all. The -all means "reject anything not on this list" which is too strict. If your email service isn't properly listed, your emails get rejected. Use ~all instead, which means "mark as suspicious" rather than outright rejection.Another mistake is adding your email service to a subdomain but forgetting to add it to your main domain. If you send from hello@yourcompany.com, make sure your main domain's SPF record includes your email service.Example SPF records:If you're using Google Workspace and AutoSend:v=spf1 include:_spf.google.com include:amazonses.com ~allIf you're using Google Workspace and SendGrid:v=spf1 include:_spf.google.com include:sendgrid.net ~allIf you're using Microsoft 365 and Postmark:v=spf1 include:spf.protection.outlook.com include:spf.mtasv.net ~allThe pattern is always: v=spf1 followed by domains, ending with ~all.DKIM: The Tamper-Proof SealDKIM is a digital signature that proves your email hasn't been modified in transit. Your email service signs the email with a private key, and receivers check it with a public key in your DNS.The issue happens when you have old DKIM keys from a previous email service but no keys from your current one. Or worse, empty DKIM records that say "we sign emails" but don't provide a way to verify them.Make sure you have DKIM keys from your current email service in your DNS. Your email service dashboard will show you what records to add.Example DKIM records:Most email services give you TXT records to add. For AutoSend, you might add:Record name: autosend._domainkey
Record type: TXT
Record value: p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBg...For SendGrid, it might look like:Record name: s1._domainkey.yourcompany.com
Record type: CNAME
Record value: s1.domainkey.u12345.wl.sendgrid.netFor Google Workspace, you'll get a TXT record:Record name: google._domainkey.yourcompany.com
Record type: TXT
Record value: v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBA...Your email service will provide the exact values. Just copy them into your DNS.DMARC: The Policy That Ties It TogetherDMARC tells email receivers what to do if SPF or DKIM checks fail. But it also does something tricky called "alignment checking."There are two types of alignment: strict and relaxed. Strict alignment means the domains have to match exactly. So hello@yourcompany.com and bounces@mail.yourcompany.com don't match because one uses a subdomain.Relaxed alignment is smarter. It understands that mail.yourcompany.com and yourcompany.com are part of the same organization, so it counts them as matching.Almost every email service uses subdomains for technical stuff like bounces. This is why relaxed alignment is the standard, and why strict alignment breaks things.Example DMARC records:A good starting DMARC record with relaxed alignment:Record name: _dmarc.yourcompany.com
Record type: TXT
Record value: v=DMARC1; p=none; rua=mailto:dmarc@yourcompany.com; adkim=r; aspf=rOnce you've verified everything works, change to quarantine:v=DMARC1; p=quarantine; rua=mailto:dmarc@yourcompany.com; adkim=r; aspf=r; pct=100Breaking down what each part means:v=DMARC1 - DMARC versionp=quarantine - Put suspicious emails in spam (use p=none while testing)rua=mailto:dmarc@yourcompany.com - Where to send reportsadkim=r - Relaxed DKIM alignment (this is the important one)aspf=r - Relaxed SPF alignment (also important)pct=100 - Apply policy to 100% of emailsThe key parts are adkim=r and aspf=r. These need to be set to r (relaxed) not s (strict).How to Figure Out What's WrongFirst, check your actual DNS records. Don't trust what your DNS service provider's dashboard says. Use a command line tool or an online DNS checker to see what's actually there. Look up your domain's TXT records and your DMARC records.Common things you'll find: multiple DMARC records (you can only have one), strict alignment enabled when it should be relaxed, or your email service missing from your main domain's SPF record.Next, send yourself a test email and look at the raw headers. In Gmail, click the three dots and choose "Show original." Look for the Return-Path and Authentication-Results headers. This will show you exactly what's failing.If you've set up DMARC reports (the rua= part of your DMARC record), you'll get XML reports showing authentication failures. They're ugly to read but they tell you exactly what's going wrong. Just give it to Claude or ChatGPT for interpretation. The FixThe fix usually involves three changes.Change your DMARC to relaxed alignment. Find your DMARC record and look for adkim=s; aspf=s. Change both of those to r instead of s. This tells email receivers that subdomains are okay as long as they're part of the same organization.Add your email service to your main domain's SPF record. If you're using AutoSend, add include:amazonses.com to your SPF record. For SendGrid, add include:sendgrid.net. For Postmark, add include:spf.mtasv.net. Your email service's documentation will tell you what to add.Change -all to ~all in your SPF record. This changes from "reject" to "mark as suspicious" which is safer and more forgiving if something goes wrong.That's it. No content changes, no IP warming, no deliverability magic. Just three DNS updates and your emails will stop showing warnings.Quick ChecklistIf you're seeing warnings, here's what to check. Is your email service included in your main domain's SPF record? Are you using ~all at the end of that record instead of -all? Do you have DKIM keys from your current email service in your DNS? Do you have only one DMARC record with relaxed alignment?Send yourself a test email and check the headers in Gmail (three dots, then Show original). Make sure SPF, DKIM, and DMARC all show as passing.Why This Matters NowEmail authentication has been around for years, but Gmail and Yahoo made their requirements stricter in 2024. What used to work fine might now trigger warnings.That orange warning banner kills trust. But it's fixable with DNS records. Once you understand what SPF, DKIM, and DMARC actually do, fixing them is straightforward.Think of it this way: SPF says who can send emails for you. DKIM proves the email hasn't been tampered with. DMARC says what to do if those checks fail. Get those three working with relaxed alignment and you're done.One More ThingEmail authentication shouldn't be this confusing. The problem is that most email services just give you DNS records to copy without explaining what they do or why they matter.If you're stuck on this, check your email service's documentation for their SPF and DKIM setup instructions. Most have a support article that walks through it step by step.And if you're still seeing warnings after making these changes, reach out to your email service's support. They can usually spot the issue in a few minutes since they've seen it hundreds of times before.The key is understanding that strict alignment is what breaks things for most people. Switch to relaxed alignment and make sure your email service is properly authorized in your DNS. That solves it 90% of the time.Bonus tip: Disable open rate tracking for your emails if you're using a new domain to send emails.

Gmail marking your emails as suspicious? Fix DMARC strict alignment with this SPF, DKIM, and DMARC DNS configuration guide.

Why Gmail Says Your Emails "Appear Suspicious" (And How to Fix It)

You're staring at your email dashboard. Open rate: 24%. Click rate: 3.2%. Unsubscribe rate: 0.8%.Are those numbers good? Bad? Should you change something, or keep doing what you're doing?Most email analytics dashboards throw numbers at you with zero context. You see percentages and graphs, but no explanation of what they actually mean or what to do about them. Even worse, the metrics people obsess over most (like open rates) are increasingly unreliable.Here's what actually matters: complaint rates tell you if people hate your emails. Bounce rates show list quality and technical issues. Click-through rates reveal genuine engagement. Unsubscribe patterns indicate content fit. And when you read these metrics together instead of in isolation, they tell you exactly what's working and what needs to fix.This guide breaks down each metric that actually impacts your email performance. For each one, you'll learn what it measures, what healthy benchmarks look like, what trends mean, and what action to take. By the end, you'll know how to read your email analytics like a pro and make data-driven improvements.Let's start with why everyone's favorite metric is fundamentally broken.<h2>Why Open Rates Don't Mean What They Used To</h2>Open rates used to be simple: someone opened your email, a tiny tracking pixel loaded, and you counted it as an open.Then Apple Mail Privacy Protection came along. Now when Apple Mail users download emails, Apple's servers pre-load all images and tracking pixels automatically, whether the person actually opened the email or not. This happens for roughly 40-50% of email users, and that percentage keeps growing.The result: your open rates are inflated with phantom opens from people who never actually saw your email. A 35% open rate might really be 20%. You have no way to know which opens are real and which are Apple's servers.Open rates aren't useless, but they're no longer reliable as a primary metric. You can still track trends (if your open rate suddenly drops from 30% to 15%, something's wrong), but don't make decisions based on absolute numbers or small changes.Here's what to track instead.<h2>Complaint Rate: Your Most Critical Metric</h2>Complaint rate is the percentage of recipients who marked your email as spam. This is the single most important number in your analytics because it directly destroys your sender reputation.Email service providers watch this metric obsessively. If your complaint rate goes above 0.1% (1 complaint per 1,000 emails), you're in dangerous territory. Above 0.3%, you're likely to get throttled or blacklisted.Healthy benchmark: Under 0.1% Warning zone: 0.1% - 0.3% Critical: Above 0.3%What trends mean:A sudden spike in complaints usually means something specific went wrong. You sent to an old list, your subject line was misleading, you emailed people who unsubscribed, or your content was completely off-brand from what people expected.Gradual increases mean you're slowly losing relevance with your audience. Your content isn't matching what people signed up for, or you're sending too frequently.What to do:If you see a spike, immediately identify what was different about that send. Different subject line? New list segment? Content change? Stop that immediately.If complaints are gradually rising, segment your list and look at who's complaining. Are they new subscribers or old? Did they come from a specific signup source? Are certain email types getting more complaints than others? This tells you where the mismatch is.Never ignore complaints. Every person who hits the spam button is telling both you and their email provider that you're unwanted. Fix it fast.<hr><h2>Bounce Rate: List Quality and Technical Health</h2>Bounces happen when your email can't be delivered. There are two types, and they mean very different things.Hard bounces are permanent failures. The email address doesn't exist, the domain is invalid, or the recipient's server has permanently rejected you. These addresses will never work.Soft bounces are temporary. The recipient's inbox is full, their server is down, or the email was too large. These might work if you try again later.Healthy benchmarks: Hard bounce rate: Under 2% Soft bounce rate: Under 5%What trends mean:High hard bounce rates indicate list quality problems. You're either collecting email addresses incorrectly, buying lists (don't), or haven't cleaned your list in forever. Hard bounces also include spam traps, which will destroy your reputation.Rising soft bounce rates usually mean technical issues. Your emails might be too large, your content triggers receiving server filters, or you're hitting rate limits.What to do:Remove hard bounces from your list immediately. There's no point sending to addresses that don't exist, and it hurts your sender reputation every time you try.For soft bounces, AutoSend will retry a few times before giving up. If an address soft bounces repeatedly over weeks, treat it like a hard bounce and remove it.If your hard bounce rate is above 4%, you have a serious list quality problem. Stop sending, figure out where bad addresses are coming from, and clean your list. At AutoSend, we automatically suppress hard bounces so you don't keep hitting dead addresses, but you need to fix the source of the problem.<h2>Click-Through Rate: Actual Engagement</h2>Click-through rate (CTR) is the percentage of recipients who clicked a link in your email. Unlike open rates, clicks are reliable. Someone either clicked or they didn't.This is your best measure of genuine engagement. It tells you if your content is interesting enough to act on, if your calls-to-action are working, and if you're reaching people who actually care.Healthy benchmarks: Transactional emails: 10-20% Marketing emails: 2-5% Cold outreach: 1-3%These vary wildly by industry and email type, so track your own baseline and measure against that.What trends mean:Declining CTR means your content is becoming less relevant. Your subject lines might be misleading (high opens, low clicks), your CTAs are unclear, or you're sending to disengaged subscribers.High opens with low clicks specifically means a mismatch between subject line and content. People open expecting one thing and get something else.Low opens with high clicks means your subject lines are weak but your content is strong. The people who do open are engaged.What to do:If clicks are declining across all emails, you have a content problem. Survey your audience, test different formats, or segment more carefully to match content to interests.If specific emails have low CTR, look at the email itself. Is the CTA clear? Are you asking too much? Is there too much text before the link? Test different approaches.Track which links get clicked. If you have five links but everyone only clicks one, that tells you what people actually care about. Double down on that.<hr><h2>Unsubscribe Rate: Signal vs Noise</h2>Unsubscribe rate is the percentage of recipients who opted out. This metric confuses people because it's not inherently bad.Some unsubscribes are healthy. People's needs change, they no longer need your product, or they signed up for one thing and you're sending another. It's better they unsubscribe than mark you as spam.Healthy benchmark: 0.2% - 0.5% per sendWhat trends mean:A sudden spike in unsubscribes (above 1%) means something was wrong with that specific email. Misleading subject line, content completely off-brand, wrong audience segment, or you accidentally sent to an old/inactive list.Gradual increases mean slow relevance decay. You're losing alignment with your audience's interests.Very low unsubscribe rates (under 0.1%) combined with low engagement might mean your unsubscribe link is hard to find, which is worse. People will just mark you as spam instead.What to do:If you see a spike, figure out what was different about that send, just like with complaints. But don't panic over normal unsubscribe rates. Losing people who aren't interested is good for your engagement metrics and sender reputation.If unsubscribes are trending up slowly, segment your list and see who's leaving. New subscribers? Old ones? Specific signup sources? This tells you where the mismatch is happening.The worst scenario is high unsubscribes AND high complaints. That means people are so annoyed they're taking two different actions to stop hearing from you. Fix this immediately.<hr><h2>Conversion Rate: The Bottom Line</h2>Conversion rate measures how many recipients took the action you actually wanted. Made a purchase, signed up for something, downloaded a resource, replied to your email, whatever your goal was.This is the metric that matters to your business, but it's also the hardest to track because it requires connecting email clicks to actions taken elsewhere.Healthy benchmarks: These vary so wildly by industry, email type, and goal that generic benchmarks are useless. Track your own baseline.What trends mean:Low conversion despite high CTR means your landing page or offer is the problem, not your email. People are interested enough to click but something on the other side isn't working.Low conversion with low CTR means the email itself isn't compelling enough to get people to take the first step.What to do:Make sure you're actually tracking conversions. Use UTM parameters, conversion pixels, or unique tracking links so you can attribute actions back to specific emails.If clicks are high but conversions are low, fix what happens after the click. Test your landing page, simplify the conversion path, or adjust your offer.If both clicks and conversions are low, the problem is in the email. Test different subject lines, content formats, and CTAs.<hr><h2>Time-to-Open and Time-to-Click Patterns</h2>Most people don't think about timing, but when people open and click tells you a lot.If 80% of your opens happen in the first hour after sending, your subject line is strong and your audience is engaged. If opens trickle in over days, you're hitting inactive users or your content isn't time-sensitive enough to prioritize.Click timing is even more interesting. Fast clicks (within minutes of opening) suggest impulse actions or high-intent content. Delayed clicks might mean people are reading carefully or coming back to something they saved.What to do:Look at when your emails get the most engagement and send during those windows. If your audience opens emails at 8am on Tuesdays, don't send at 3pm on Fridays.For transactional emails, fast open times are critical. If it takes hours for someone to see their password reset, that's a problem. Check if your sending is delayed or if emails are getting filtered.Track how timing correlates with conversions. Sometimes the people who click immediately convert poorly (impulse, not ready), while delayed clicks convert better (thoughtful consideration). This changes how you optimize.<hr><h2>Re-Engagement Patterns</h2>This isn't a single metric but a pattern to watch: how often do the same people engage with your emails over time?Some subscribers open everything you send. Others open once every few months. Some clicked five emails in a row, then nothing for weeks. These patterns tell you who's genuinely engaged versus who's passively on your list.What to track:Segment your list by engagement recency. Who opened in the last 7 days? 30 days? 90 days? Never?Watch for engagement decay. If someone goes from opening every email to opening every third email to not opening at all, they're slowly churning. Catch them before they're completely disengaged.What to do:Create win-back campaigns for people who haven't engaged in 60-90 days. Ask if they still want to hear from you, offer to change email frequency, or give them a compelling reason to re-engage.For your most engaged subscribers, consider sending them more content or exclusive offers. These are your best customers, don't ignore them by treating everyone the same.Regularly clean your list by removing people who haven't engaged in 6+ months. They're hurting your metrics and costing you money with no benefit.<hr><h2>How to Read Metrics Together</h2>Individual metrics are useful, but reading them in combination tells you what's actually happening.High opens, low clicks: Subject line works but content doesn't deliver. Your emails promise one thing and deliver another, or your CTAs are weak.Low opens, high clicks: Subject lines are terrible but content is great. The people who do open are highly engaged. Improve your subject lines.High clicks, low conversions: Email is working, but your landing page, offer, or next step is broken. Fix what happens after the click.Rising unsubscribes, stable complaints: People are politely leaving instead of marking you spam. Content mismatch, but you're making it easy to opt out. Good.Rising complaints, rising unsubscribes: People are so frustrated they're taking multiple actions to stop hearing from you. Major content problem or you're emailing the wrong people.High bounces, high complaints: List quality disaster. You're sending to bad addresses and the ones that do exist don't want your emails. Stop immediately and clean your list.Declining engagement across all metrics: General relevance decay. Your content is becoming less interesting, you're sending too frequently, or your audience is changing and you're not adapting.Look at your metrics together every week, not just when something goes wrong. Patterns emerge over time that aren't visible in single sends.<hr><h2>Vanity Metrics That Don't Actually Matter</h2>Some metrics look impressive but tell you nothing useful:Total subscribers: Meaningless without engagement rates. 100,000 subscribers with 1% engagement is worse than 10,000 with 20% engagement. Quality over quantity always.Email sent count: Sending more emails doesn't mean anything if they're not being read or acted on. Don't celebrate volume, celebrate engagement.List growth rate: Growing fast is only good if you're growing with engaged, relevant subscribers. Adding 1,000 people who never open your emails hurts more than it helps.Delivery rate: This just means the email technically arrived at a server somewhere. It doesn't mean it hit the inbox versus the spam folder. Focus on engagement, not technical delivery.Stop tracking these or at least stop making decisions based on them. They make you feel good without indicating real email health.<hr><h2>Start With the Metrics That Impact Deliverability</h2>You don't need to track everything at once. Start with the metrics that directly impact your sender reputation: complaint rate, bounce rate, and engagement patterns.Get those right and you'll land in inboxes consistently. Then layer in conversion tracking and more sophisticated analysis as you scale.The goal isn't to obsess over numbers. It's to understand what your audience is telling you through their behavior and respond accordingly. Low engagement means your content isn't relevant. High complaints mean you're annoying people. Rising bounces mean your list is degrading.Fix the signals, and the numbers will improve naturally.

You're staring at your email dashboard. Open rate: 24%. Click rate: 3.2%. Unsubscribe rate: 0.8%.Are those numbers good? Bad? Should you change something, or keep doing what you're doing?Most email analytics dashboards throw numbers at you with zero context. You see percentages and graphs, but no explanation of what they actually mean or what to do about them. Even worse, the metrics people obsess over most (like open rates) are increasingly unreliable.Here's what actually matters: complaint rates tell you if people hate your emails. Bounce rates show list quality and technical issues. Click-through rates reveal genuine engagement. Unsubscribe patterns indicate content fit. And when you read these metrics together instead of in isolation, they tell you exactly what's working and what needs to fix.This guide breaks down each metric that actually impacts your email performance. For each one, you'll learn what it measures, what healthy benchmarks look like, what trends mean, and what action to take. By the end, you'll know how to read your email analytics like a pro and make data-driven improvements.Let's start with why everyone's favorite metric is fundamentally broken.Why Open Rates Don't Mean What They Used ToOpen rates used to be simple: someone opened your email, a tiny tracking pixel loaded, and you counted it as an open.Then Apple Mail Privacy Protection came along. Now when Apple Mail users download emails, Apple's servers pre-load all images and tracking pixels automatically, whether the person actually opened the email or not. This happens for roughly 40-50% of email users, and that percentage keeps growing.The result: your open rates are inflated with phantom opens from people who never actually saw your email. A 35% open rate might really be 20%. You have no way to know which opens are real and which are Apple's servers.Open rates aren't useless, but they're no longer reliable as a primary metric. You can still track trends (if your open rate suddenly drops from 30% to 15%, something's wrong), but don't make decisions based on absolute numbers or small changes.Here's what to track instead.Complaint Rate: Your Most Critical MetricComplaint rate is the percentage of recipients who marked your email as spam. This is the single most important number in your analytics because it directly destroys your sender reputation.Email service providers watch this metric obsessively. If your complaint rate goes above 0.1% (1 complaint per 1,000 emails), you're in dangerous territory. Above 0.3%, you're likely to get throttled or blacklisted.Healthy benchmark: Under 0.1%Warning zone: 0.1% - 0.3%Critical: Above 0.3%What trends mean:A sudden spike in complaints usually means something specific went wrong. You sent to an old list, your subject line was misleading, you emailed people who unsubscribed, or your content was completely off-brand from what people expected.Gradual increases mean you're slowly losing relevance with your audience. Your content isn't matching what people signed up for, or you're sending too frequently.What to do:If you see a spike, immediately identify what was different about that send. Different subject line? New list segment? Content change? Stop that immediately.If complaints are gradually rising, segment your list and look at who's complaining. Are they new subscribers or old? Did they come from a specific signup source? Are certain email types getting more complaints than others? This tells you where the mismatch is.Never ignore complaints. Every person who hits the spam button is telling both you and their email provider that you're unwanted. Fix it fast.Bounce Rate: List Quality and Technical HealthBounces happen when your email can't be delivered. There are two types, and they mean very different things.Hard bounces are permanent failures. The email address doesn't exist, the domain is invalid, or the recipient's server has permanently rejected you. These addresses will never work.Soft bounces are temporary. The recipient's inbox is full, their server is down, or the email was too large. These might work if you try again later.Healthy benchmarks:Hard bounce rate: Under 2%Soft bounce rate: Under 5%What trends mean:High hard bounce rates indicate list quality problems. You're either collecting email addresses incorrectly, buying lists (don't), or haven't cleaned your list in forever. Hard bounces also include spam traps, which will destroy your reputation.Rising soft bounce rates usually mean technical issues. Your emails might be too large, your content triggers receiving server filters, or you're hitting rate limits.What to do:Remove hard bounces from your list immediately. There's no point sending to addresses that don't exist, and it hurts your sender reputation every time you try.For soft bounces, AutoSend will retry a few times before giving up. If an address soft bounces repeatedly over weeks, treat it like a hard bounce and remove it.If your hard bounce rate is above 4%, you have a serious list quality problem. Stop sending, figure out where bad addresses are coming from, and clean your list. At AutoSend, we automatically suppress hard bounces so you don't keep hitting dead addresses, but you need to fix the source of the problem.Click-Through Rate: Actual EngagementClick-through rate (CTR) is the percentage of recipients who clicked a link in your email. Unlike open rates, clicks are reliable. Someone either clicked or they didn't.This is your best measure of genuine engagement. It tells you if your content is interesting enough to act on, if your calls-to-action are working, and if you're reaching people who actually care.Healthy benchmarks:Transactional emails: 10-20%Marketing emails: 2-5%Cold outreach: 1-3%These vary wildly by industry and email type, so track your own baseline and measure against that.What trends mean:Declining CTR means your content is becoming less relevant. Your subject lines might be misleading (high opens, low clicks), your CTAs are unclear, or you're sending to disengaged subscribers.High opens with low clicks specifically means a mismatch between subject line and content. People open expecting one thing and get something else.Low opens with high clicks means your subject lines are weak but your content is strong. The people who do open are engaged.What to do:If clicks are declining across all emails, you have a content problem. Survey your audience, test different formats, or segment more carefully to match content to interests.If specific emails have low CTR, look at the email itself. Is the CTA clear? Are you asking too much? Is there too much text before the link? Test different approaches.Track which links get clicked. If you have five links but everyone only clicks one, that tells you what people actually care about. Double down on that.Unsubscribe Rate: Signal vs NoiseUnsubscribe rate is the percentage of recipients who opted out. This metric confuses people because it's not inherently bad.Some unsubscribes are healthy. People's needs change, they no longer need your product, or they signed up for one thing and you're sending another. It's better they unsubscribe than mark you as spam.Healthy benchmark: 0.2% - 0.5% per sendWhat trends mean:A sudden spike in unsubscribes (above 1%) means something was wrong with that specific email. Misleading subject line, content completely off-brand, wrong audience segment, or you accidentally sent to an old/inactive list.Gradual increases mean slow relevance decay. You're losing alignment with your audience's interests.Very low unsubscribe rates (under 0.1%) combined with low engagement might mean your unsubscribe link is hard to find, which is worse. People will just mark you as spam instead.What to do:If you see a spike, figure out what was different about that send, just like with complaints. But don't panic over normal unsubscribe rates. Losing people who aren't interested is good for your engagement metrics and sender reputation.If unsubscribes are trending up slowly, segment your list and see who's leaving. New subscribers? Old ones? Specific signup sources? This tells you where the mismatch is happening.The worst scenario is high unsubscribes AND high complaints. That means people are so annoyed they're taking two different actions to stop hearing from you. Fix this immediately.Conversion Rate: The Bottom LineConversion rate measures how many recipients took the action you actually wanted. Made a purchase, signed up for something, downloaded a resource, replied to your email, whatever your goal was.This is the metric that matters to your business, but it's also the hardest to track because it requires connecting email clicks to actions taken elsewhere.Healthy benchmarks:These vary so wildly by industry, email type, and goal that generic benchmarks are useless. Track your own baseline.What trends mean:Low conversion despite high CTR means your landing page or offer is the problem, not your email. People are interested enough to click but something on the other side isn't working.Low conversion with low CTR means the email itself isn't compelling enough to get people to take the first step.What to do:Make sure you're actually tracking conversions. Use UTM parameters, conversion pixels, or unique tracking links so you can attribute actions back to specific emails.If clicks are high but conversions are low, fix what happens after the click. Test your landing page, simplify the conversion path, or adjust your offer.If both clicks and conversions are low, the problem is in the email. Test different subject lines, content formats, and CTAs.Time-to-Open and Time-to-Click PatternsMost people don't think about timing, but when people open and click tells you a lot.If 80% of your opens happen in the first hour after sending, your subject line is strong and your audience is engaged. If opens trickle in over days, you're hitting inactive users or your content isn't time-sensitive enough to prioritize.Click timing is even more interesting. Fast clicks (within minutes of opening) suggest impulse actions or high-intent content. Delayed clicks might mean people are reading carefully or coming back to something they saved.What to do:Look at when your emails get the most engagement and send during those windows. If your audience opens emails at 8am on Tuesdays, don't send at 3pm on Fridays.For transactional emails, fast open times are critical. If it takes hours for someone to see their password reset, that's a problem. Check if your sending is delayed or if emails are getting filtered.Track how timing correlates with conversions. Sometimes the people who click immediately convert poorly (impulse, not ready), while delayed clicks convert better (thoughtful consideration). This changes how you optimize.Re-Engagement PatternsThis isn't a single metric but a pattern to watch: how often do the same people engage with your emails over time?Some subscribers open everything you send. Others open once every few months. Some clicked five emails in a row, then nothing for weeks. These patterns tell you who's genuinely engaged versus who's passively on your list.What to track:Segment your list by engagement recency. Who opened in the last 7 days? 30 days? 90 days? Never?Watch for engagement decay. If someone goes from opening every email to opening every third email to not opening at all, they're slowly churning. Catch them before they're completely disengaged.What to do:Create win-back campaigns for people who haven't engaged in 60-90 days. Ask if they still want to hear from you, offer to change email frequency, or give them a compelling reason to re-engage.For your most engaged subscribers, consider sending them more content or exclusive offers. These are your best customers, don't ignore them by treating everyone the same.Regularly clean your list by removing people who haven't engaged in 6+ months. They're hurting your metrics and costing you money with no benefit.How to Read Metrics TogetherIndividual metrics are useful, but reading them in combination tells you what's actually happening.High opens, low clicks: Subject line works but content doesn't deliver. Your emails promise one thing and deliver another, or your CTAs are weak.Low opens, high clicks: Subject lines are terrible but content is great. The people who do open are highly engaged. Improve your subject lines.High clicks, low conversions: Email is working, but your landing page, offer, or next step is broken. Fix what happens after the click.Rising unsubscribes, stable complaints: People are politely leaving instead of marking you spam. Content mismatch, but you're making it easy to opt out. Good.Rising complaints, rising unsubscribes: People are so frustrated they're taking multiple actions to stop hearing from you. Major content problem or you're emailing the wrong people.High bounces, high complaints: List quality disaster. You're sending to bad addresses and the ones that do exist don't want your emails. Stop immediately and clean your list.Declining engagement across all metrics: General relevance decay. Your content is becoming less interesting, you're sending too frequently, or your audience is changing and you're not adapting.Look at your metrics together every week, not just when something goes wrong. Patterns emerge over time that aren't visible in single sends.Vanity Metrics That Don't Actually MatterSome metrics look impressive but tell you nothing useful:Total subscribers: Meaningless without engagement rates. 100,000 subscribers with 1% engagement is worse than 10,000 with 20% engagement. Quality over quantity always.Email sent count: Sending more emails doesn't mean anything if they're not being read or acted on. Don't celebrate volume, celebrate engagement.List growth rate: Growing fast is only good if you're growing with engaged, relevant subscribers. Adding 1,000 people who never open your emails hurts more than it helps.Delivery rate: This just means the email technically arrived at a server somewhere. It doesn't mean it hit the inbox versus the spam folder. Focus on engagement, not technical delivery.Stop tracking these or at least stop making decisions based on them. They make you feel good without indicating real email health.Start With the Metrics That Impact DeliverabilityYou don't need to track everything at once. Start with the metrics that directly impact your sender reputation: complaint rate, bounce rate, and engagement patterns.Get those right and you'll land in inboxes consistently. Then layer in conversion tracking and more sophisticated analysis as you scale.The goal isn't to obsess over numbers. It's to understand what your audience is telling you through their behavior and respond accordingly. Low engagement means your content isn't relevant. High complaints mean you're annoying people. Rising bounces mean your list is degrading.Fix the signals, and the numbers will improve naturally.

Email metrics explained: what each number means, healthy benchmarks, red flags to watch for, and how to turn analytics into better email performance.

How to Read Email Metrics and Actually Improve Email Performance

You already know which emails are the problem.The welcome email that 30% of new users never see. The password reset buried under Gmail's Promotions tab. The product update your customers swear they never received.Most frustrating part of email is, these problems are very hard to find and figure out. You might think all of this is happening because of the email content. But many times it's a technical or behavioral mistake that spam filters have been trained to catch and most of them are completely fixable once you know what to look for.I run AutoSend, an email service that helps you send transactional and marketing emails. I have seen many of our customers making these mistakes constantly.A customer with 100k sending volume reached out to us because none of their campaigns were working out. I check their setup and spot it immediately: they're sending from noreply@, and they just blasted 17,000 emails from a three-week-old domain.These aren't edge cases. They're the most common reasons emails land in spam.<h2>Quick Self-Diagnosis</h2>Before reading the full guide, check these first. If any of these are true, fix them before anything else:<ol><li>SPF record missing or misconfigured</li><li>DKIM not enabled on your sending domain</li><li>DMARC policy not set</li><li> Sending from noreply@ or no-reply@</li><li> Domain is less than 60 days old and you're sending volume</li><li>No unsubscribe link in marketing emails</li><li>Complaint rate above 0.1%</li><li>Bounce rate above 3%</li></ol>If you checked two or more of these, start there. Those are your biggest deliverability killers.<h2>Critical Mistakes (Fix These First)</h2>These will get you blacklisted or blocked fast. If you're making any of these, everything else is secondary.<h3>1. Missing Email Authentication (SPF, DKIM, DMARC)</h3>Why it causes spam: Inbox providers treat unauthenticated emails as impersonation attempts, with no way to verify you are who you claim to be.Inbox providers automatically flag unauthenticated emails as potential impersonation attempts. Without these three protocols configured, your emails have no way to prove they're legitimately from you.How to fix it: Set up all three in your DNS records. Verify they're working with a tool like MXToolbox or <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="http://mail-tester.com">mail-tester.com</a>. If you're sending through AutoSend, we verify your DKIM during domain setup. You'll see a green check in your dashboard once it's confirmed.For a full walkthrough: <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/blog/how-spf-dkim-and-dmarc-work">How SPF, DKIM, and DMARC Work Together</a><h3>2. Sending from noreply@ or no-reply@</h3>You might want to send OTPs and transactional email via no-reply email ids as this is a standard practice. But, if your domain is new and you do not have much sending reputation, try to avoid it. These addresses signal to spam filters that you don't want engagement, which is exactly what spam does. Inbox providers prioritize emails that look like two-way communication.How to fix it: Use a real address. hello@, support@, team@, or your own name. If you need to suppress replies for a specific email type, use a filter on the inbox instead of a dead-address sender.But honestly, it's the best if you receive replies to your emails. That signals you are a legitimate sender and ISPs will start trusting you.<h3>3. Deleting Contacts and Re-Uploading to Bypass Unsubscribes</h3>This one is a BIG NO! This violates CAN-SPAM and GDPR. When users get emails they already unsubscribed from, they report spam immediately. Your domain reputation tanks fast and the damage is hard to recover from.How to fix it: Never delete suppression lists. They're not a list of failures. They're a record of people who have the legal right not to hear from you. Honor them permanently. If you want to re-engage, run a proper win-back campaign to people who simply stopped opening, not people who explicitly opted out.<h3>4. Missing Unsubscribe Link or Postal Address</h3>CAN-SPAM requires a working unsubscribe mechanism and a physical postal address in every commercial email. No exceptions.How to fix it: Every marketing email needs a one-click unsubscribe and your business address in the footer. <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/blog/do-transactional-emails-need-an-unsubscribe-link">Transactional emails do not strictly need unsubscribe link</a>. You can mention them as system-notifications. But if the email has any promotional element, you need it.<h2>High-Impact Mistakes</h2>These won't get you blacklisted overnight, but they cause a steady reputation decline. If you're seeing a gradual drop in deliverability or inconsistent inbox placement, one of these is likely the cause.<h3>5. Blasting Volume from a Brand New Domain</h3>A new domain has zero sending history. When you immediately send thousands of emails from it, you look exactly like a spam operation — because that's also what spam operations do.How to fix it: Warm up your domain over 2–4 weeks. Start with 50–100 emails per day to your most engaged contacts. Gradually increase volume. This builds the reputation signal that inbox providers need before they'll trust you at scale.Full guide: <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/blog/new-email-domain-warmup-guide">How to Warm Up a New Email Domain</a><h3>6. Cold Emailing from a New Domain</h3>A new domain plus unsolicited emails is a double red flag. Even legitimate cold outreach needs a warmed domain first.How to fix it: Before you start any cold outreach, spend at least two weeks warming your domain with transactional or engaged-subscriber email. Keep cold outreach volume small and separate it from your main sending domain if possible.<h3>7. Using URL Shorteners (<a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="http://bit.ly">bit.ly</a>, tinyurl, etc.)</h3>Spammers use URL shorteners to hide malicious destinations, so filters treat them as a red flag regardless of who's using them. Also, it is hard for the users to see the actual URL and trust your email. So while you are sending your email, think of every possible way to increase trust of your users. Show all your links, let them see what they are clicking on and committing to. This engagement with your email is going to help you build trust.How to fix it: Use full destination URLs. If you need click tracking, use a custom domain short link that's authenticated and associated with your brand.<blockquote>Note: If you're using AutoSend's click tracking, we handle this automatically using our branded tracking domain, so your links stay clean.</blockquote><h3>8. Purchased or Scraped Email Lists</h3>These lists contain spam traps, inactive addresses, and people who never gave any permission to hear from you. Your complaint rate spikes immediately, and that damage follows your domain.How to fix it: Only email people who explicitly opted in. No shortcuts here. If you're trying to build a list fast, focus on owned channels — product signups, content opt-ins, referrals.<h3>9. Mismatched From and Reply-To Domains</h3>When your From address is @<a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="http://yourcompany.com">yourcompany.com</a> but your Reply-To is @<a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="http://anotherdomain.com">anotherdomain.com</a>, it looks like a phishing setup, because that's how phishing emails are often structured.How to fix it: Keep both addresses on the same authenticated domain. If you genuinely need replies to go somewhere else, make sure both domains are authenticated and the difference is explained clearly to recipients.<h2>For Developers Sending Transactional Email via API</h2>This section is specifically for developers sending transactional email programmatically including password resets, receipts, notifications, onboarding sequences. The mistakes here are different from marketing email issues and they're often invisible until something breaks badly.<h3>10. Not Handling Bounces via Webhook</h3>If your application keeps retrying sends to addresses that hard bounced, your reputation degrades quickly. Most developers don't realize their email provider is silently logging bounces while their code keeps firing.How to fix it: Set up webhook listeners for bounce and complaint events. Hard bounces should be suppressed immediately. Soft bounces should be retried a limited number of times before suppression.In AutoSend, bounce and complaint webhooks are available under Settings &gt; Webhooks.<h3>11. Sending All Email Types from the Same Domain</h3>Mixing your transactional email (password resets, receipts) with your marketing email (campaigns, newsletters) on one domain is risky. A spam complaint from a marketing email can affect deliverability for your transactional email.How to fix it: Use a subdomain for transactional email maybe <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="http://mail.yourdomain.com">mail.yourdomain.com</a> or <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="http://notifications.yourdomain.com">notifications.yourdomain.com</a>. This separates the reputation so a marketing issue doesn't interrupt your product's critical email flow.<h3>12. Not Monitoring Complaint Rate</h3>Most developers check delivery rates but not complaint rates. Gmail's Postmaster Tools and inbox providers surface complaint data that your sending platform alone won't show you.How to fix it: Set up [Google Postmaster Tools](<a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://postmaster.google.com">https://postmaster.google.com</a>) for your sending domain. Your complaint rate should stay below 0.1%. Above 0.3% and you're in danger of bulk filtering. AutoSend's Email Activity dashboard also surfaces complaint events in real time.<h3>13. Ignoring Soft Bounces</h3>Soft bounces (mailbox full, temporary server error) are often overlooked because emails eventually get through. But a pattern of soft bounces to the same address signals list hygiene problems.How to fix it: Track soft bounce patterns. If an address soft bounces three or more times in a row, treat it as a hard bounce and suppress it.<h2>Medium-Impact Mistakes</h2>These increase your spam score incrementally. None of them will tank you alone, but in combination, especially with one of the above, they push you over the threshold.<h3>14. Poor Text-to-Image Ratio</h3>Emails that are mostly images with little text look like advertisements to spam filters, and they have nothing to analyze for content signals. They're also bad for accessibility and dark mode.How to fix it: Keep a 60/40 or 70/30 text-to-image ratio. Always include a plain text version of every email. If you're sending HTML, make sure the copy carries the message even without images loading.<h3>15. Too Many Links</h3>Each link adds to your spam score, and 10+ links in a single email looks like a link farm. Spam filters count them.How to fix it: Keep it to 3–5 links maximum. Every link should have a clear purpose. If you're finding yourself adding more, it's a sign the email is trying to do too many things at once.<h3>16. Spammy Subject Lines</h3>"URGENT!!!", "You've been selected", "Re:" with no prior thread, these trigger filters and erode recipient trust even when they don't land in spam. Don't create urgency for people to act on something.How to fix it: Write subject lines that accurately describe what's inside. If the email is worth sending, the subject line shouldn't need to manufacture urgency. Specificity beats clickbait every time.<h3>17. Generic Greetings</h3>"Dear Friend", "Hello there", "Hey valued customer", generic greetings tell spam filters (and recipients) that you don't actually know who you're writing to.How to fix it: Use first name personalization. If you don't have their name, consider whether you should be emailing them at all.<h3>18. Excessive Capitalization and Exclamation Marks</h3>WRITING IN ALL CAPS or piling on exclamation marks triggers filters and looks unprofessional. Spam has trained both algorithms and people to associate these patterns with low-quality senders.How to fix it: Write like a human having a normal conversation. If your email needs ALL CAPS to feel urgent, the problem is the message, not the formatting.<hr><h2>Closing note</h2>You don't need to fix all 18 at once. Work through them in order of severity:1. Critical first: Authentication (SPF, DKIM, DMARC), list hygiene, legal compliance2. Then high-impact: Domain warmup, bounce handling, list quality3. Then developer-specific: Webhook setup, subdomain separation, monitoring4. Medium last: Formatting, subject lines, content patternsMost of the critical and high-impact fixes are one-time setups. Do them once, do them right, and they stop being a problem.The medium-impact ones are habits. They get easier once you've internalized what spam filters are actually looking for: signs that a real person sent this to another real person who wanted to receive it.The bottom line for emails is, be genuine with your users and you will get more value from everyone. Email is a 40-year-old technology, so in whatever way you try to hack it, it will catch you and that will impact your business directly. So best way is to go slowly and genuinely.<hr><h3>Need Help With Sending Emails?</h3>If you're dealing with a specific deliverability issue, complaint rate spikes, sudden inbox placement drops, or setting up a new sending domain from scratch, I'm happy to take a look.AutoSend gives you full visibility into your email activity, bounce and complaint webhooks, domain warmup and a clean API that handles a lot of these best practices by default. If you are looking to send transactional, marketing or automation emails, you should check this out.<a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://asend.email/demo">Book a 20-minute call</a> or <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com">sign up and start autosending</a>.

You already know which emails are the problem.The welcome email that 30% of new users never see. The password reset buried under Gmail's Promotions tab. The product update your customers swear they never received.Most frustrating part of email is, these problems are very hard to find and figure out. You might think all of this is happening because of the email content. But many times it's a technical or behavioral mistake that spam filters have been trained to catch and most of them are completely fixable once you know what to look for.I run AutoSend, an email service that helps you send transactional and marketing emails. I have seen many of our customers making these mistakes constantly.A customer with 100k sending volume reached out to us because none of their campaigns were working out. I check their setup and spot it immediately: they're sending from noreply@, and they just blasted 17,000 emails from a three-week-old domain.These aren't edge cases. They're the most common reasons emails land in spam.Quick Self-DiagnosisBefore reading the full guide, check these first. If any of these are true, fix them before anything else:SPF record missing or misconfiguredDKIM not enabled on your sending domainDMARC policy not set Sending from noreply@ or no-reply@ Domain is less than 60 days old and you're sending volumeNo unsubscribe link in marketing emailsComplaint rate above 0.1%Bounce rate above 3%If you checked two or more of these, start there. Those are your biggest deliverability killers.Critical Mistakes (Fix These First)These will get you blacklisted or blocked fast. If you're making any of these, everything else is secondary.1. Missing Email Authentication (SPF, DKIM, DMARC)Why it causes spam: Inbox providers treat unauthenticated emails as impersonation attempts, with no way to verify you are who you claim to be.Inbox providers automatically flag unauthenticated emails as potential impersonation attempts. Without these three protocols configured, your emails have no way to prove they're legitimately from you.How to fix it: Set up all three in your DNS records. Verify they're working with a tool like MXToolbox or mail-tester.com. If you're sending through AutoSend, we verify your DKIM during domain setup. You'll see a green check in your dashboard once it's confirmed.For a full walkthrough: How SPF, DKIM, and DMARC Work Together2. Sending from noreply@ or no-reply@You might want to send OTPs and transactional email via no-reply email ids as this is a standard practice. But, if your domain is new and you do not have much sending reputation, try to avoid it. These addresses signal to spam filters that you don't want engagement, which is exactly what spam does. Inbox providers prioritize emails that look like two-way communication.How to fix it: Use a real address. hello@, support@, team@, or your own name. If you need to suppress replies for a specific email type, use a filter on the inbox instead of a dead-address sender.But honestly, it's the best if you receive replies to your emails. That signals you are a legitimate sender and ISPs will start trusting you.3. Deleting Contacts and Re-Uploading to Bypass UnsubscribesThis one is a BIG NO! This violates CAN-SPAM and GDPR. When users get emails they already unsubscribed from, they report spam immediately. Your domain reputation tanks fast and the damage is hard to recover from.How to fix it: Never delete suppression lists. They're not a list of failures. They're a record of people who have the legal right not to hear from you. Honor them permanently. If you want to re-engage, run a proper win-back campaign to people who simply stopped opening, not people who explicitly opted out.4. Missing Unsubscribe Link or Postal AddressCAN-SPAM requires a working unsubscribe mechanism and a physical postal address in every commercial email. No exceptions.How to fix it: Every marketing email needs a one-click unsubscribe and your business address in the footer. Transactional emails do not strictly need unsubscribe link. You can mention them as system-notifications. But if the email has any promotional element, you need it.High-Impact MistakesThese won't get you blacklisted overnight, but they cause a steady reputation decline. If you're seeing a gradual drop in deliverability or inconsistent inbox placement, one of these is likely the cause.5. Blasting Volume from a Brand New DomainA new domain has zero sending history. When you immediately send thousands of emails from it, you look exactly like a spam operation — because that's also what spam operations do.How to fix it: Warm up your domain over 2–4 weeks. Start with 50–100 emails per day to your most engaged contacts. Gradually increase volume. This builds the reputation signal that inbox providers need before they'll trust you at scale.Full guide: How to Warm Up a New Email Domain6. Cold Emailing from a New DomainA new domain plus unsolicited emails is a double red flag. Even legitimate cold outreach needs a warmed domain first.How to fix it: Before you start any cold outreach, spend at least two weeks warming your domain with transactional or engaged-subscriber email. Keep cold outreach volume small and separate it from your main sending domain if possible.7. Using URL Shorteners (bit.ly, tinyurl, etc.)Spammers use URL shorteners to hide malicious destinations, so filters treat them as a red flag regardless of who's using them. Also, it is hard for the users to see the actual URL and trust your email. So while you are sending your email, think of every possible way to increase trust of your users. Show all your links, let them see what they are clicking on and committing to. This engagement with your email is going to help you build trust.How to fix it: Use full destination URLs. If you need click tracking, use a custom domain short link that's authenticated and associated with your brand.Note: If you're using AutoSend's click tracking, we handle this automatically using our branded tracking domain, so your links stay clean.8. Purchased or Scraped Email ListsThese lists contain spam traps, inactive addresses, and people who never gave any permission to hear from you. Your complaint rate spikes immediately, and that damage follows your domain.How to fix it: Only email people who explicitly opted in. No shortcuts here. If you're trying to build a list fast, focus on owned channels — product signups, content opt-ins, referrals.9. Mismatched From and Reply-To DomainsWhen your From address is @yourcompany.com but your Reply-To is @anotherdomain.com, it looks like a phishing setup, because that's how phishing emails are often structured.How to fix it: Keep both addresses on the same authenticated domain. If you genuinely need replies to go somewhere else, make sure both domains are authenticated and the difference is explained clearly to recipients.For Developers Sending Transactional Email via APIThis section is specifically for developers sending transactional email programmatically including password resets, receipts, notifications, onboarding sequences. The mistakes here are different from marketing email issues and they're often invisible until something breaks badly.10. Not Handling Bounces via WebhookIf your application keeps retrying sends to addresses that hard bounced, your reputation degrades quickly. Most developers don't realize their email provider is silently logging bounces while their code keeps firing.How to fix it: Set up webhook listeners for bounce and complaint events. Hard bounces should be suppressed immediately. Soft bounces should be retried a limited number of times before suppression.In AutoSend, bounce and complaint webhooks are available under Settings &gt; Webhooks.11. Sending All Email Types from the Same DomainMixing your transactional email (password resets, receipts) with your marketing email (campaigns, newsletters) on one domain is risky. A spam complaint from a marketing email can affect deliverability for your transactional email.How to fix it: Use a subdomain for transactional email maybe mail.yourdomain.com or notifications.yourdomain.com. This separates the reputation so a marketing issue doesn't interrupt your product's critical email flow.12. Not Monitoring Complaint RateMost developers check delivery rates but not complaint rates. Gmail's Postmaster Tools and inbox providers surface complaint data that your sending platform alone won't show you.How to fix it: Set up [Google Postmaster Tools](https://postmaster.google.com) for your sending domain. Your complaint rate should stay below 0.1%. Above 0.3% and you're in danger of bulk filtering. AutoSend's Email Activity dashboard also surfaces complaint events in real time.13. Ignoring Soft BouncesSoft bounces (mailbox full, temporary server error) are often overlooked because emails eventually get through. But a pattern of soft bounces to the same address signals list hygiene problems.How to fix it: Track soft bounce patterns. If an address soft bounces three or more times in a row, treat it as a hard bounce and suppress it.Medium-Impact MistakesThese increase your spam score incrementally. None of them will tank you alone, but in combination, especially with one of the above, they push you over the threshold.14. Poor Text-to-Image RatioEmails that are mostly images with little text look like advertisements to spam filters, and they have nothing to analyze for content signals. They're also bad for accessibility and dark mode.How to fix it: Keep a 60/40 or 70/30 text-to-image ratio. Always include a plain text version of every email. If you're sending HTML, make sure the copy carries the message even without images loading.15. Too Many LinksEach link adds to your spam score, and 10+ links in a single email looks like a link farm. Spam filters count them.How to fix it: Keep it to 3–5 links maximum. Every link should have a clear purpose. If you're finding yourself adding more, it's a sign the email is trying to do too many things at once.16. Spammy Subject Lines"URGENT!!!", "You've been selected", "Re:" with no prior thread, these trigger filters and erode recipient trust even when they don't land in spam. Don't create urgency for people to act on something.How to fix it: Write subject lines that accurately describe what's inside. If the email is worth sending, the subject line shouldn't need to manufacture urgency. Specificity beats clickbait every time.17. Generic Greetings"Dear Friend", "Hello there", "Hey valued customer", generic greetings tell spam filters (and recipients) that you don't actually know who you're writing to.How to fix it: Use first name personalization. If you don't have their name, consider whether you should be emailing them at all.18. Excessive Capitalization and Exclamation MarksWRITING IN ALL CAPS or piling on exclamation marks triggers filters and looks unprofessional. Spam has trained both algorithms and people to associate these patterns with low-quality senders.How to fix it: Write like a human having a normal conversation. If your email needs ALL CAPS to feel urgent, the problem is the message, not the formatting.Closing noteYou don't need to fix all 18 at once. Work through them in order of severity:1. Critical first: Authentication (SPF, DKIM, DMARC), list hygiene, legal compliance2. Then high-impact: Domain warmup, bounce handling, list quality3. Then developer-specific: Webhook setup, subdomain separation, monitoring4. Medium last: Formatting, subject lines, content patternsMost of the critical and high-impact fixes are one-time setups. Do them once, do them right, and they stop being a problem.The medium-impact ones are habits. They get easier once you've internalized what spam filters are actually looking for: signs that a real person sent this to another real person who wanted to receive it.The bottom line for emails is, be genuine with your users and you will get more value from everyone. Email is a 40-year-old technology, so in whatever way you try to hack it, it will catch you and that will impact your business directly. So best way is to go slowly and genuinely.Need Help With Sending Emails?If you're dealing with a specific deliverability issue, complaint rate spikes, sudden inbox placement drops, or setting up a new sending domain from scratch, I'm happy to take a look.AutoSend gives you full visibility into your email activity, bounce and complaint webhooks, domain warmup and a clean API that handles a lot of these best practices by default. If you are looking to send transactional, marketing or automation emails, you should check this out.Book a 20-minute call or sign up and start autosending.

Most deliverability problems come down to a small set of fixable mistakes. Let's discuss 18 mistakes, what they are, why they happen, and how to fix each one.

Why Your Emails Go to Spam: 18 Reasons and How to Fix Each One

Starting to send emails from a brand new domain without proper preparation will land your messages in spam folders. Email providers like Gmail, Outlook, and Yahoo don't trust new domains by default. They have no history with you, no data on whether you're a legitimate sender or a spammer.This is where domain warming comes in. It's the process of gradually building your sender reputation by slowly increasing your email volume over 4-8 weeks while maintaining strong engagement metrics. Skip this step, and you'll spend months fighting deliverability problems. Do it properly, and you'll establish a foundation for consistently high inbox placement.This guide covers everything you need to know about warming up a new domain for both transactional and marketing emails.<h2>Why Domain Warming Matters</h2>Email providers like Gmail, Outlook, and Yahoo don't trust new domains by default. They have no history with you. No data on whether your emails are legitimate or spam. So they watch closely.When you suddenly start sending thousands of emails from a fresh domain, it triggers red flags. The algorithm thinks: "This looks like a spammer who just registered a domain." Your emails get filtered, your domain gets a poor reputation score, and you're starting from a much worse position than if you'd warmed up properly.The warming process proves you're legitimate. You're gradually increasing volume, maintaining good engagement, and following email best practices. This builds sender reputation and trains inbox providers to trust your domain.<h2>Before You Start: Technical Foundation</h2>Domain warming isn't just about volume. You need the technical infrastructure in place first.Set up your DNS authentication records properly. This means SPF, DKIM, and DMARC. These records verify that you're authorized to send emails from your domain and help prevent spoofing. Without them, you'll struggle to reach inboxes regardless of how slowly you ramp up. If you need help with the technical setup, check out <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/blog/how-spf-dkim-and-dmarc-work">how SPF, DKIM, and DMARC works</a>.If you're using AutoSend, <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://docs.autosend.com/domain">here's how to setup DNS records.</a>Use a dedicated subdomain for email. Avoid sending from your main domain like <code>example.com</code>. Use a subdomain like <code>mail.example.com</code> or <code>send.example.com</code>. This protects your main domain's reputation if something goes wrong with your email sending. It also gives you better control over authentication and monitoring.Set up proper reverse DNS (rDNS). Your IP address should have a PTR record that points back to your sending domain. Most email service providers including AutoSend handle this automatically, but verify it's configured correctly.Create a real postmaster and abuse email address. Set up <code>postmaster@yourdomain.com</code> and <code>abuse@yourdomain.com</code> that actually receive mail. Inbox providers check these addresses and may send important feedback to them.Configure your email infrastructure. Whether you're using AutoSend or another provider, make sure your <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/transactional-emails">email API</a> integration is working, you can track bounces and complaints, and your webhook endpoints are ready to receive delivery events.<h2>Understanding the Warming Timeline</h2>The warming process typically takes 4-8 weeks depending on your sending volume. Here's why it takes this long:Inbox providers are watching multiple signals over time. They look at your sending patterns, engagement rates, spam complaints, bounce rates, and consistency. They need enough data to establish that you're a legitimate sender. Rushing this process by jumping to high volume too quickly will hurt your reputation.Different volume levels require different approaches. Sending 1,000 emails per day requires a different strategy than sending 100,000 per day.<h2>The Week-by-Week Warming Schedule</h2>For Low Volume Senders (up to 5,000 emails/day)<ol><li>Week 1: Start with 50-100 emails per day. Send to your most engaged contacts. These should be people who definitely want your emails and are likely to open them.</li><li>Week 2: Increase to 200-500 emails per day. Maintain high engagement by sending relevant content.</li><li>Week 3: Move to 1,000-2,000 emails per day. You can start including slightly less engaged contacts, but still focus on quality over quantity.</li><li>Week 4: Reach 3,000-5,000 emails per day. By now, you should see consistent deliverability and can operate at your target volume.</li></ol>For Medium Volume Senders (5,000-50,000 emails/day)<ol><li>Week 1: Send 200-500 emails per day to your most engaged segments.</li><li>Week 2: Increase to 1,000-2,000 emails per day.</li><li>Week 3: Jump to 5,000-10,000 emails per day.</li><li>Week 4: Reach 15,000-20,000 emails per day.</li><li>Week 5: Scale to 30,000-40,000 emails per day.</li><li>Week 6: Hit your target volume of 50,000 emails per day.</li></ol>For High Volume Senders (50,000+ emails/day)<ol><li>Week 1-2: Start with 500-1,000 emails per day, focusing exclusively on highly engaged contacts.</li><li>Week 3-4: Increase to 10,000-20,000 emails per day.</li><li>Week 5-6: Scale to 40,000-80,000 emails per day.</li><li>Week 7-8: Reach 100,000+ emails per day and maintain consistent patterns.</li></ol>For high volume sending, you may want to split across multiple dedicated IPs and warm each IP separately following a similar schedule.<h2>The Most Important Rule: Consistency</h2>Don't send 1,000 emails on Monday, skip Tuesday, send 5,000 on Wednesday, and nothing on Thursday. Inconsistent sending patterns look suspicious to inbox providers.Send every day or every business day during your warming period. Maintain a regular schedule. If you're warming up for a newsletter that goes out weekly, send smaller test batches to engaged contacts on your off days to maintain consistency.Keep your daily volume increases gradual. Don't double your volume overnight. A 30-50% increase every few days is much safer than aggressive jumps.<h2>Engagement is Your Best Friend</h2>Inbox providers measure engagement heavily. Opens, clicks, replies, and forwards signal that people want your emails. Spam complaints, deletes without opening, and ignoring your emails signal the opposite.Start with your most engaged contacts. These are people who have recently interacted with you, explicitly opted in, or have a history of engagement. For transactional emails, this means customers who just completed an action. For marketing, this means subscribers who recently joined your list or have opened recent emails.Send content people actually want. During warming, every email matters. Don't send mediocre content just to hit your daily volume. Send your best stuff. If you're warming a transactional domain, trigger real, valuable notifications. If you're warming a marketing domain, send genuinely useful content to subscribers who will appreciate it.Avoid sending to old, cold lists during warming. That list of 50,000 contacts you collected over three years? Don't send to them during warming. Many of those email addresses are probably dead, the engaged people have moved on, and you'll see terrible metrics. Save cold reactivation campaigns for after you've established your reputation.Make it easy to engage. Use clear, compelling subject lines. Make your emails mobile-friendly. Include a clear call-to-action. The easier you make it for people to engage positively, the better your reputation will be.<h2>Segmentation Strategy During Warming</h2>For marketing email warming, segment your list by engagement level. Create tiers:Tier 1 - Highly Engaged: Opened or clicked in the last 30 days, recent subscribers, customers who regularly interact with you.Tier 2 - Moderately Engaged: Opened in the last 90 days, less frequent but consistent engagement.Tier 3 - Low Engagement: Opened in the last 180 days, infrequent interaction.Tier 4 - Cold/Unengaged: No opens in 180+ days, very old subscribers.During warming, follow this sequence:<ul><li>Weeks 1-2: Only Tier 1</li><li>Weeks 3-4: Tier 1 + Tier 2</li><li>Weeks 5-6: Tier 1 + Tier 2 + Tier 3</li><li>Week 7+: All tiers, but consider a reactivation campaign for Tier 4</li></ul><h2>Transactional vs. Marketing Email Warming</h2>The principles are the same, but the execution differs.<a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/blog/how-to-warm-up-a-new-domain-for-transactional-emails">Transactional email warming</a> is often easier because engagement rates are naturally higher. People want their receipts, notifications, and account updates. Your strategy should focus on:<ul><li>Starting with the most critical, time-sensitive notifications first. Password resets and order confirmations have the highest engagement. Gradually add less critical notifications like weekly digests or feature announcements.</li><li>Maintaining consistent daily volume by staggering non-urgent notifications if needed. If you don't have enough natural transactional volume during warming, you can supplement with well-targeted marketing content to engaged users.</li><li>Avoiding bulk promotional sends during the warming period. Save marketing campaigns for after you've established transactional credibility.</li></ul>Marketing email warming requires more careful planning because engagement rates vary more. Your strategy should emphasize:<ul><li>Building a warming calendar with your best content scheduled for the warming period. Don't waste your warming sends on weak campaigns.</li><li>Segmenting aggressively by engagement level as described above. Never send to your full list during warming.</li><li>Adjusting your normal send schedule if needed. If you usually send twice a week, continue that schedule but only to your most engaged segments initially.</li></ul>Creating special content that encourages engagement during warming. Ask questions, run polls, share genuinely valuable resources. This isn't the time for hard sells.<h2>Monitoring Your Progress</h2>Track these metrics daily during warming:Delivery rate: Should stay above 95%. If it drops, you have list quality issues or technical problems.Bounce rate: Should be under 3%, ideally under 1%. High bounces damage your reputation quickly. Remove bounced addresses immediately and investigate why you're seeing bounces.Spam complaint rate: Must stay under 0.1% (1 complaint per 1,000 emails). Anything higher is a serious problem. If you're seeing high complaints, stop sending, identify the issue, and fix it before continuing.Open rate: This varies by industry, but you want to see consistent or improving open rates as you warm up. If open rates drop as you increase volume, you're scaling too fast or including less engaged contacts too early.Click rate: Similar to open rate. Stable or improving click rates indicate healthy engagement.Spam folder placement: Use seed testing tools to check where your emails land across different providers. If you're hitting spam folders frequently, slow down your warming and improve engagement.Most email service providers give you access to these metrics in real-time. <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline underline underline underline-offset-2 decoration-1 decoration-current/40 hover:decoration-current focus:decoration-current" href="https://autosend.io">AutoSend</a> shows all of this in your dashboard, including detailed activity tracking and webhook events for bounces and complaints.<h2>Tools for Testing and Monitoring</h2><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline underline underline underline-offset-2 decoration-1 decoration-current/40 hover:decoration-current focus:decoration-current" href="https://www.mail-tester.com/">Mail-Tester</a>: Quick check of your email's spam score and technical setup. Useful for spot-checking during warming.<a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline underline underline underline-offset-2 decoration-1 decoration-current/40 hover:decoration-current focus:decoration-current" href="https://glockapps.com/">GlockApps</a>: Send test emails to seed lists across major providers and see exactly where you land. Use this weekly during warming to catch deliverability issues early.<a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline underline underline underline-offset-2 decoration-1 decoration-current/40 hover:decoration-current focus:decoration-current" href="https://postmaster.google.com/">Google Postmaster Tools</a>: If you're sending significant volume to Gmail addresses, set up Postmaster Tools. It shows your domain reputation, spam rate, and feedback loop data directly from Google.<a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline underline underline underline-offset-2 decoration-1 decoration-current/40 hover:decoration-current focus:decoration-current" href="https://sendersupport.olc.protection.outlook.com/snds/">Microsoft SNDS</a>: Similar to Google Postmaster but for Outlook/Hotmail. Monitor your IP reputation and complaint rates.Your email provider's analytics: Whatever platform you're using should give you detailed metrics. Check them daily during warming and watch for trends.<h2>Common Mistakes to Avoid</h2>Don't buy or scrape email lists. This kills your reputation instantly. Only send to people who explicitly opted in to receive your emails.Don't send from free email provider addresses (Gmail, Yahoo, etc.) for bulk sending. Use your own domain with proper authentication.Don't ignore bounces and complaints. These are direct signals that something is wrong. Address them immediately.Don't use misleading subject lines or hide your identity. This generates complaints and damages trust.Don't forget to include a working unsubscribe link. It's required by law and helps maintain a healthy list. People who unsubscribe are better than people who mark you as spam.Don't panic if you see occasional spam folder placement during warming. Some variation is normal. Look for trends, not individual incidents.<h2>Special Scenarios</h2>Warming multiple domains: If you need to send from multiple domains, warm each separately. Don't try to transfer reputation from one domain to another. You can run warming processes in parallel if needed.Adding a new IP address: If you're adding a new dedicated IP to an already-warmed domain, you still need to warm the IP. Use a similar schedule but you can move slightly faster since your domain already has reputation.Switching email providers: Your domain reputation follows your domain, not your provider. However, you may need a brief re-warming period (1-2 weeks) when switching providers, especially if moving to dedicated IPs.Seasonal senders: If you only send emails seasonally, plan extra time for warming when you start each season. Your reputation degrades over time without sending activity.<h2>After Warming: Maintaining Your Reputation</h2>Once you've completed your warming schedule and reached your target volume, the work isn't over. Sender reputation requires ongoing maintenance.Keep sending consistently. Large gaps in sending or dramatic volume changes can hurt your reputation even after warming.Continue monitoring your metrics. If you see bounce rates creeping up or engagement dropping, investigate immediately.Clean your list regularly. Remove bounces immediately, suppress complaints, and consider removing addresses that haven't engaged in 6-12 months.Segment your sends to maintain good engagement. Don't send everything to everyone just because you can.Test new content approaches gradually. If you want to try a new format or messaging strategy, test with your most engaged segments first.<h2>Starting Your Warming Process</h2>Domain warming requires patience, but it's worth the investment. A properly warmed domain with strong reputation delivers better results for years. Rushing the process saves you a few weeks now but costs you months of poor deliverability later.Start with your technical foundation. Make sure your DNS authentication is correct and your infrastructure is ready. Then begin sending small volumes to your most engaged contacts and gradually scale up following the schedules outlined above.Monitor your metrics daily. Stay consistent with your sending. Focus on engagement over volume. And give yourself the full 4-8 weeks to establish your reputation properly.The domains that skip warming are the ones dealing with spam folder problems six months later. The domains that warm properly are the ones hitting inboxes consistently and driving real results from their email programs.

Starting to send emails from a brand new domain without proper preparation will land your messages in spam folders. Email providers like Gmail, Outlook, and Yahoo don't trust new domains by default. They have no history with you, no data on whether you're a legitimate sender or a spammer.This is where domain warming comes in. It's the process of gradually building your sender reputation by slowly increasing your email volume over 4-8 weeks while maintaining strong engagement metrics. Skip this step, and you'll spend months fighting deliverability problems. Do it properly, and you'll establish a foundation for consistently high inbox placement.This guide covers everything you need to know about warming up a new domain for both transactional and marketing emails.Why Domain Warming MattersEmail providers like Gmail, Outlook, and Yahoo don't trust new domains by default. They have no history with you. No data on whether your emails are legitimate or spam. So they watch closely.When you suddenly start sending thousands of emails from a fresh domain, it triggers red flags. The algorithm thinks: "This looks like a spammer who just registered a domain." Your emails get filtered, your domain gets a poor reputation score, and you're starting from a much worse position than if you'd warmed up properly.The warming process proves you're legitimate. You're gradually increasing volume, maintaining good engagement, and following email best practices. This builds sender reputation and trains inbox providers to trust your domain.Before You Start: Technical FoundationDomain warming isn't just about volume. You need the technical infrastructure in place first.Set up your DNS authentication records properly. This means SPF, DKIM, and DMARC. These records verify that you're authorized to send emails from your domain and help prevent spoofing. Without them, you'll struggle to reach inboxes regardless of how slowly you ramp up. If you need help with the technical setup, check out how SPF, DKIM, and DMARC works.If you're using AutoSend, here's how to setup DNS records.Use a dedicated subdomain for email. Avoid sending from your main domain like example.com. Use a subdomain like mail.example.com or send.example.com. This protects your main domain's reputation if something goes wrong with your email sending. It also gives you better control over authentication and monitoring.Set up proper reverse DNS (rDNS). Your IP address should have a PTR record that points back to your sending domain. Most email service providers including AutoSend handle this automatically, but verify it's configured correctly.Create a real postmaster and abuse email address. Set up postmaster@yourdomain.com and abuse@yourdomain.com that actually receive mail. Inbox providers check these addresses and may send important feedback to them.Configure your email infrastructure. Whether you're using AutoSend or another provider, make sure your email API integration is working, you can track bounces and complaints, and your webhook endpoints are ready to receive delivery events.Understanding the Warming TimelineThe warming process typically takes 4-8 weeks depending on your sending volume. Here's why it takes this long:Inbox providers are watching multiple signals over time. They look at your sending patterns, engagement rates, spam complaints, bounce rates, and consistency. They need enough data to establish that you're a legitimate sender. Rushing this process by jumping to high volume too quickly will hurt your reputation.Different volume levels require different approaches. Sending 1,000 emails per day requires a different strategy than sending 100,000 per day.The Week-by-Week Warming ScheduleFor Low Volume Senders (up to 5,000 emails/day)Week 1: Start with 50-100 emails per day. Send to your most engaged contacts. These should be people who definitely want your emails and are likely to open them.Week 2: Increase to 200-500 emails per day. Maintain high engagement by sending relevant content.Week 3: Move to 1,000-2,000 emails per day. You can start including slightly less engaged contacts, but still focus on quality over quantity.Week 4: Reach 3,000-5,000 emails per day. By now, you should see consistent deliverability and can operate at your target volume.For Medium Volume Senders (5,000-50,000 emails/day)Week 1: Send 200-500 emails per day to your most engaged segments.Week 2: Increase to 1,000-2,000 emails per day.Week 3: Jump to 5,000-10,000 emails per day.Week 4: Reach 15,000-20,000 emails per day.Week 5: Scale to 30,000-40,000 emails per day.Week 6: Hit your target volume of 50,000 emails per day.For High Volume Senders (50,000+ emails/day)Week 1-2: Start with 500-1,000 emails per day, focusing exclusively on highly engaged contacts.Week 3-4: Increase to 10,000-20,000 emails per day.Week 5-6: Scale to 40,000-80,000 emails per day.Week 7-8: Reach 100,000+ emails per day and maintain consistent patterns.For high volume sending, you may want to split across multiple dedicated IPs and warm each IP separately following a similar schedule.The Most Important Rule: ConsistencyDon't send 1,000 emails on Monday, skip Tuesday, send 5,000 on Wednesday, and nothing on Thursday. Inconsistent sending patterns look suspicious to inbox providers.Send every day or every business day during your warming period. Maintain a regular schedule. If you're warming up for a newsletter that goes out weekly, send smaller test batches to engaged contacts on your off days to maintain consistency.Keep your daily volume increases gradual. Don't double your volume overnight. A 30-50% increase every few days is much safer than aggressive jumps.Engagement is Your Best FriendInbox providers measure engagement heavily. Opens, clicks, replies, and forwards signal that people want your emails. Spam complaints, deletes without opening, and ignoring your emails signal the opposite.Start with your most engaged contacts. These are people who have recently interacted with you, explicitly opted in, or have a history of engagement. For transactional emails, this means customers who just completed an action. For marketing, this means subscribers who recently joined your list or have opened recent emails.Send content people actually want. During warming, every email matters. Don't send mediocre content just to hit your daily volume. Send your best stuff. If you're warming a transactional domain, trigger real, valuable notifications. If you're warming a marketing domain, send genuinely useful content to subscribers who will appreciate it.Avoid sending to old, cold lists during warming. That list of 50,000 contacts you collected over three years? Don't send to them during warming. Many of those email addresses are probably dead, the engaged people have moved on, and you'll see terrible metrics. Save cold reactivation campaigns for after you've established your reputation.Make it easy to engage. Use clear, compelling subject lines. Make your emails mobile-friendly. Include a clear call-to-action. The easier you make it for people to engage positively, the better your reputation will be.Segmentation Strategy During WarmingFor marketing email warming, segment your list by engagement level. Create tiers:Tier 1 - Highly Engaged: Opened or clicked in the last 30 days, recent subscribers, customers who regularly interact with you.Tier 2 - Moderately Engaged: Opened in the last 90 days, less frequent but consistent engagement.Tier 3 - Low Engagement: Opened in the last 180 days, infrequent interaction.Tier 4 - Cold/Unengaged: No opens in 180+ days, very old subscribers.During warming, follow this sequence:Weeks 1-2: Only Tier 1Weeks 3-4: Tier 1 + Tier 2Weeks 5-6: Tier 1 + Tier 2 + Tier 3Week 7+: All tiers, but consider a reactivation campaign for Tier 4Transactional vs. Marketing Email WarmingThe principles are the same, but the execution differs.Transactional email warming is often easier because engagement rates are naturally higher. People want their receipts, notifications, and account updates. Your strategy should focus on:Starting with the most critical, time-sensitive notifications first. Password resets and order confirmations have the highest engagement. Gradually add less critical notifications like weekly digests or feature announcements.Maintaining consistent daily volume by staggering non-urgent notifications if needed. If you don't have enough natural transactional volume during warming, you can supplement with well-targeted marketing content to engaged users.Avoiding bulk promotional sends during the warming period. Save marketing campaigns for after you've established transactional credibility.Marketing email warming requires more careful planning because engagement rates vary more. Your strategy should emphasize:Building a warming calendar with your best content scheduled for the warming period. Don't waste your warming sends on weak campaigns.Segmenting aggressively by engagement level as described above. Never send to your full list during warming.Adjusting your normal send schedule if needed. If you usually send twice a week, continue that schedule but only to your most engaged segments initially.Creating special content that encourages engagement during warming. Ask questions, run polls, share genuinely valuable resources. This isn't the time for hard sells.Monitoring Your ProgressTrack these metrics daily during warming:Delivery rate: Should stay above 95%. If it drops, you have list quality issues or technical problems.Bounce rate: Should be under 3%, ideally under 1%. High bounces damage your reputation quickly. Remove bounced addresses immediately and investigate why you're seeing bounces.Spam complaint rate: Must stay under 0.1% (1 complaint per 1,000 emails). Anything higher is a serious problem. If you're seeing high complaints, stop sending, identify the issue, and fix it before continuing.Open rate: This varies by industry, but you want to see consistent or improving open rates as you warm up. If open rates drop as you increase volume, you're scaling too fast or including less engaged contacts too early.Click rate: Similar to open rate. Stable or improving click rates indicate healthy engagement.Spam folder placement: Use seed testing tools to check where your emails land across different providers. If you're hitting spam folders frequently, slow down your warming and improve engagement.Most email service providers give you access to these metrics in real-time. AutoSend shows all of this in your dashboard, including detailed activity tracking and webhook events for bounces and complaints.Tools for Testing and MonitoringMail-Tester: Quick check of your email's spam score and technical setup. Useful for spot-checking during warming.GlockApps: Send test emails to seed lists across major providers and see exactly where you land. Use this weekly during warming to catch deliverability issues early.Google Postmaster Tools: If you're sending significant volume to Gmail addresses, set up Postmaster Tools. It shows your domain reputation, spam rate, and feedback loop data directly from Google.Microsoft SNDS: Similar to Google Postmaster but for Outlook/Hotmail. Monitor your IP reputation and complaint rates.Your email provider's analytics: Whatever platform you're using should give you detailed metrics. Check them daily during warming and watch for trends.Common Mistakes to AvoidDon't buy or scrape email lists. This kills your reputation instantly. Only send to people who explicitly opted in to receive your emails.Don't send from free email provider addresses (Gmail, Yahoo, etc.) for bulk sending. Use your own domain with proper authentication.Don't ignore bounces and complaints. These are direct signals that something is wrong. Address them immediately.Don't use misleading subject lines or hide your identity. This generates complaints and damages trust.Don't forget to include a working unsubscribe link. It's required by law and helps maintain a healthy list. People who unsubscribe are better than people who mark you as spam.Don't panic if you see occasional spam folder placement during warming. Some variation is normal. Look for trends, not individual incidents.Special ScenariosWarming multiple domains: If you need to send from multiple domains, warm each separately. Don't try to transfer reputation from one domain to another. You can run warming processes in parallel if needed.Adding a new IP address: If you're adding a new dedicated IP to an already-warmed domain, you still need to warm the IP. Use a similar schedule but you can move slightly faster since your domain already has reputation.Switching email providers: Your domain reputation follows your domain, not your provider. However, you may need a brief re-warming period (1-2 weeks) when switching providers, especially if moving to dedicated IPs.Seasonal senders: If you only send emails seasonally, plan extra time for warming when you start each season. Your reputation degrades over time without sending activity.After Warming: Maintaining Your ReputationOnce you've completed your warming schedule and reached your target volume, the work isn't over. Sender reputation requires ongoing maintenance.Keep sending consistently. Large gaps in sending or dramatic volume changes can hurt your reputation even after warming.Continue monitoring your metrics. If you see bounce rates creeping up or engagement dropping, investigate immediately.Clean your list regularly. Remove bounces immediately, suppress complaints, and consider removing addresses that haven't engaged in 6-12 months.Segment your sends to maintain good engagement. Don't send everything to everyone just because you can.Test new content approaches gradually. If you want to try a new format or messaging strategy, test with your most engaged segments first.Starting Your Warming ProcessDomain warming requires patience, but it's worth the investment. A properly warmed domain with strong reputation delivers better results for years. Rushing the process saves you a few weeks now but costs you months of poor deliverability later.Start with your technical foundation. Make sure your DNS authentication is correct and your infrastructure is ready. Then begin sending small volumes to your most engaged contacts and gradually scale up following the schedules outlined above.Monitor your metrics daily. Stay consistent with your sending. Focus on engagement over volume. And give yourself the full 4-8 weeks to establish your reputation properly.The domains that skip warming are the ones dealing with spam folder problems six months later. The domains that warm properly are the ones hitting inboxes consistently and driving real results from their email programs.

Learn how to warm up a new email domain with proven schedules and strategies. Avoid spam folders and build lasting sender reputation.

How to Warm Up a New Email Domain: Step-by-Step Guide for High Deliverability

If your legitimate emails are landing in spam or being spoofed by attackers, your authentication setup might be the problem. To make sure your emails are trusted, you need three essential protocols: SPF, DKIM, and DMARC.These technologies form the foundation of secure email delivery. Together, they prevent phishing, domain impersonation, and spam, ensuring that your messages reach the inbox safely.This guide explains what each protocol does, how they work together, and how to set them up correctly.<h2>Why Email Authentication Matters</h2>Every day, millions of phishing emails are sent pretending to be from legitimate companies. Without proper authentication, spammers can forge your domain name and send fake messages that look real.Strong email authentication:<ul><li>Protects your brand reputation</li><li>Improves deliverability</li><li>Increases user trust</li><li>Prevents unauthorized senders from using your domain</li></ul><h2>What Is SPF?</h2><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/spf-sender-policy-framework">SPF (Sender Policy Framework)</a> is a DNS record that specifies which mail servers are allowed to send emails on behalf of your domain.When an email is received, the receiving mail server checks the sender’s domain and verifies if the sending IP address is listed in the SPF record.If it matches, the SPF check passes. If not, it fails and may be marked as spam or rejected.Example SPF Record<pre><code>v=spf1 include:autosend.com -all
</code></pre>How it works:<ol><li>The receiving mail server extracts the domain from the “Return-Path” header.</li><li>It looks up the SPF record for that domain.</li><li>If the IP address sending the message matches one listed, the email is authenticated.</li></ol>Best Practices for SPF<ul><li>Use <code>-all</code> instead of <code>~all</code> to enforce strict validation.</li><li>Keep the record under 10 DNS lookups to avoid breaking SPF.</li><li>Update it whenever you add or remove an email service.</li></ul><h2>What Is DKIM?</h2><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/dkim-domainkeys-identified-mail">DKIM (DomainKeys Identified Mail)</a> adds a digital signature to your emails to prove that the content has not been modified.Each outgoing email is signed with a private key that only your mail server knows. The recipient can then verify this signature using a public key stored in your domain’s DNS.Example DKIM Record<pre><code>v=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0B...
</code></pre>How it works:<ol><li>Your mail server generates a DKIM signature and attaches it to each email header.</li><li>The receiving server fetches the public key from your DNS.</li><li>It verifies the signature to ensure that the email body and headers were not altered.</li></ol>Best Practices for DKIM<ul><li>Use at least a 2048-bit key for stronger security.</li><li>Rotate DKIM keys periodically (every 6–12 months).</li><li>Ensure your “From” domain matches the signing domain for alignment with DMARC.</li></ul><h2>What Is DMARC?</h2><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/dmarc-domain-based-message-authentication-reporting-conformance">DMARC (Domain-based Message Authentication, Reporting, and Conformance)</a> ties SPF and DKIM together and defines what to do when an email fails authentication.DMARC allows you to tell receiving servers how to handle unauthenticated messages (none, quarantine, or reject) and provides detailed reports on who is sending emails using your domain.Example DMARC Record<pre><code>v=DMARC1; p=quarantine; rua=mailto:dmarc-reports@yourdomain.com; adkim=s; aspf=s
</code></pre>How it works:<ol><li>The receiving server checks if the email passes SPF or DKIM.</li><li>It verifies if the domain in those checks aligns with the “From” domain.</li><li>Based on your DMARC policy (<code>p=</code>), it either delivers, quarantines, or rejects the message.</li></ol>Policy Options<ul><li><code>p=none</code>: Monitor only (no enforcement)</li><li><code>p=quarantine</code>: Mark suspicious emails as spam</li><li><code>p=reject</code>: Block unauthorized emails entirely</li></ul>Best Practices for DMARC<ul><li>Start with <code>p=none</code> to collect reports.</li><li>Review your DMARC reports for legitimate senders.</li><li>Move to <code>quarantine</code> and finally <code>reject</code> once everything is aligned.</li></ul><h2>How SPF, DKIM, and DMARC Work Together</h2>Think of SPF, DKIM, and DMARC as three layers of email defense.Layer Purpose Protects Against SPF Authorizes sending IP addresses Spoofing and unauthorized senders DKIM Signs messages to verify integrity Message tampering DMARC Enforces policy and alignment Phishing and domain abuseHere’s how the process works when you send an email:<ol><li>The recipient’s server checks if the sending IP is authorized by SPF.</li><li>It verifies the DKIM signature to ensure the message is intact.</li><li>It applies your DMARC policy to decide what to do with emails that fail either check.</li></ol>If both SPF and DKIM align with your domain and pass validation, your message is considered legitimate.<h2>How to Set Them Up for Your Domain</h2>Setting up these records takes just a few minutes but has long-term benefits.<h3>Step 1: Add SPF Record</h3>In your DNS settings, add a TXT record:<pre><code>v=spf1 include:autosend.com -all
</code></pre><h3>Step 2: Add DKIM Record</h3>Your email service provider (like AutoSend) gives you a DKIM key. Add it as:<pre><code>default._domainkey.yourdomain.com IN TXT "v=DKIM1; k=rsa; p=MIIBIjANBgkq..."
</code></pre><h3>Step 3: Add DMARC Record</h3>Finally, publish your DMARC policy:<pre><code>_dmarc.yourdomain.com IN TXT "v=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com; aspf=s; adkim=s"
</code></pre>Once added, use tools like:<ul><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://mxtoolbox.com/">MXToolbox</a></li><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://www.dmarcanalyzer.com/">DMARC Analyzer</a></li><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://www.mail-tester.com/">Mail-Tester</a></li></ul>to confirm that everything is working.<h2>Why This Matters for Deliverability</h2>Mailbox providers like Gmail and Yahoo use these checks to decide whether to trust your domain. Without them, even legitimate emails can end up in spam. Strong authentication helps build domain reputation, leading to better inbox placement and fewer delivery issues.Once SPF, DKIM, and DMARC are properly configured, you can take authentication a step further with <a target="_new" rel="noopener" class="break-all link-break text-gray-500 hover:underline decorated-link" href="https://autosend.com/blog/how-to-get-a-verified-checkmark-in-gmail-with-bimi">BIMI (Brand Indicators for Message Identification)</a>. BIMI allows you to display your verified logo and checkmark next to your emails in supported inboxes, signaling authenticity and boosting brand trust.<hr><h2>TL;DR</h2>To protect your domain and ensure your emails reach the inbox:<ol><li>Set up SPF to authorize your sending IPs.</li><li>Enable DKIM to sign and verify message integrity.</li><li>Enforce DMARC to align and control authentication results.</li></ol>Together, these three protocols secure your brand, prevent abuse, and improve deliverability.

If your legitimate emails are landing in spam or being spoofed by attackers, your authentication setup might be the problem. To make sure your emails are trusted, you need three essential protocols: SPF, DKIM, and DMARC.These technologies form the foundation of secure email delivery. Together, they prevent phishing, domain impersonation, and spam, ensuring that your messages reach the inbox safely.This guide explains what each protocol does, how they work together, and how to set them up correctly.Why Email Authentication MattersEvery day, millions of phishing emails are sent pretending to be from legitimate companies. Without proper authentication, spammers can forge your domain name and send fake messages that look real.Strong email authentication:Protects your brand reputationImproves deliverabilityIncreases user trustPrevents unauthorized senders from using your domainWhat Is SPF?SPF (Sender Policy Framework) is a DNS record that specifies which mail servers are allowed to send emails on behalf of your domain.When an email is received, the receiving mail server checks the sender’s domain and verifies if the sending IP address is listed in the SPF record.If it matches, the SPF check passes. If not, it fails and may be marked as spam or rejected.Example SPF Recordv=spf1 include:autosend.com -all
How it works:The receiving mail server extracts the domain from the “Return-Path” header.It looks up the SPF record for that domain.If the IP address sending the message matches one listed, the email is authenticated.Best Practices for SPFUse -all instead of ~all to enforce strict validation.Keep the record under 10 DNS lookups to avoid breaking SPF.Update it whenever you add or remove an email service.What Is DKIM?DKIM (DomainKeys Identified Mail) adds a digital signature to your emails to prove that the content has not been modified.Each outgoing email is signed with a private key that only your mail server knows.The recipient can then verify this signature using a public key stored in your domain’s DNS.Example DKIM Recordv=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0B...
How it works:Your mail server generates a DKIM signature and attaches it to each email header.The receiving server fetches the public key from your DNS.It verifies the signature to ensure that the email body and headers were not altered.Best Practices for DKIMUse at least a 2048-bit key for stronger security.Rotate DKIM keys periodically (every 6–12 months).Ensure your “From” domain matches the signing domain for alignment with DMARC.What Is DMARC?DMARC (Domain-based Message Authentication, Reporting, and Conformance) ties SPF and DKIM together and defines what to do when an email fails authentication.DMARC allows you to tell receiving servers how to handle unauthenticated messages (none, quarantine, or reject) and provides detailed reports on who is sending emails using your domain.Example DMARC Recordv=DMARC1; p=quarantine; rua=mailto:dmarc-reports@yourdomain.com; adkim=s; aspf=s
How it works:The receiving server checks if the email passes SPF or DKIM.It verifies if the domain in those checks aligns with the “From” domain.Based on your DMARC policy (p=), it either delivers, quarantines, or rejects the message.Policy Optionsp=none: Monitor only (no enforcement)p=quarantine: Mark suspicious emails as spamp=reject: Block unauthorized emails entirelyBest Practices for DMARCStart with p=none to collect reports.Review your DMARC reports for legitimate senders.Move to quarantine and finally reject once everything is aligned.How SPF, DKIM, and DMARC Work TogetherThink of SPF, DKIM, and DMARC as three layers of email defense.Layer Purpose Protects Against SPF Authorizes sending IP addresses Spoofing and unauthorized senders DKIM Signs messages to verify integrity Message tampering DMARC Enforces policy and alignment Phishing and domain abuseHere’s how the process works when you send an email:The recipient’s server checks if the sending IP is authorized by SPF.It verifies the DKIM signature to ensure the message is intact.It applies your DMARC policy to decide what to do with emails that fail either check.If both SPF and DKIM align with your domain and pass validation, your message is considered legitimate.How to Set Them Up for Your DomainSetting up these records takes just a few minutes but has long-term benefits.Step 1: Add SPF RecordIn your DNS settings, add a TXT record:v=spf1 include:autosend.com -all
Step 2: Add DKIM RecordYour email service provider (like AutoSend) gives you a DKIM key.Add it as:default._domainkey.yourdomain.com IN TXT "v=DKIM1; k=rsa; p=MIIBIjANBgkq..."
Step 3: Add DMARC RecordFinally, publish your DMARC policy:_dmarc.yourdomain.com IN TXT "v=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com; aspf=s; adkim=s"
Once added, use tools like:MXToolboxDMARC AnalyzerMail-Testerto confirm that everything is working.Why This Matters for DeliverabilityMailbox providers like Gmail and Yahoo use these checks to decide whether to trust your domain.Without them, even legitimate emails can end up in spam.Strong authentication helps build domain reputation, leading to better inbox placement and fewer delivery issues.Once SPF, DKIM, and DMARC are properly configured, you can take authentication a step further with BIMI (Brand Indicators for Message Identification).BIMI allows you to display your verified logo and checkmark next to your emails in supported inboxes, signaling authenticity and boosting brand trust.TL;DRTo protect your domain and ensure your emails reach the inbox:Set up SPF to authorize your sending IPs.Enable DKIM to sign and verify message integrity.Enforce DMARC to align and control authentication results.Together, these three protocols secure your brand, prevent abuse, and improve deliverability.

Learn how SPF, DKIM, and DMARC protect your domain from spoofing and phishing, improve trust, and boost email deliverability.

How SPF, DKIM, and DMARC Work Together to Protect Your Domain

When you open an email from Apple or Google, you might notice a small blue checkmark or the brand’s official logo next to the sender’s name. That tiny icon is not decorative. It is a sign of verified authenticity, powered by BIMI (Brand Indicators for Message Identification).Implementing BIMI is one of the most effective ways to increase trust, visibility, and open rates for your <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/transactional-emails">transactional</a> and <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/marketing-emails">marketing emails</a>. This guide explains everything you need to know from DNS setup to logo requirements and verification so you can earn that verified checkmark for your brand.<h2>What Is BIMI?</h2>BIMI is an email authentication standard that allows brands to display their official logo next to their emails in recipients’ inboxes. It builds on top of <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/dmarc-domain-based-message-authentication-reporting-conformance">DMARC</a>, <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/spf-sender-policy-framework">SPF</a>, and <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/dkim-domainkeys-identified-mail">DKIM</a>, ensuring that only legitimate senders can use a company’s logo.In short:<ul><li>SPF verifies the sending IP address.</li><li>DKIM verifies that the message content has not been tampered with.</li><li>DMARC enforces alignment and policy.</li><li>BIMI adds a visual trust layer using your brand logo.</li></ul><h2>Why BIMI Matters</h2><ul><li>Boosts Trust: The verified logo signals authenticity and reduces phishing risk.</li><li>Increases Open Rates: Emails with visible brand logos stand out in crowded inboxes.</li><li>Enhances Brand Recognition: Your logo appears alongside your sender name across supported email clients.</li><li>Supports Deliverability: BIMI indirectly improves domain reputation through strong authentication.</li></ul><h2>Email Clients That Support BIMI</h2>BIMI is still growing in adoption but is already supported by major inbox providers.Currently supported by:<ul><li>Gmail (requires a Verified Mark Certificate)</li><li>Yahoo Mail</li><li>Apple Mail (macOS and iOS 16 and above)</li><li>Fastmail</li><li>AOL Mail</li></ul><h2>Step-by-Step Guide to Getting the Verified Checkmark with BIMI</h2>There are four main steps to implement BIMI correctly:<ol><li>Set up email authentication</li><li>Create and host your logo in the right format</li><li>Obtain a Verified Mark Certificate (VMC)</li><li>Publish your BIMI DNS record</li></ol>Let’s go through each step in detail.<h3>Step 1: Set Up Email Authentication (SPF, DKIM, and DMARC)</h3>BIMI works only if your email domain passes all authentication checks.1. Configure SPFSPF (Sender Policy Framework) ensures that only your authorized servers can send emails on behalf of your domain.Example DNS TXT record:<pre><code>v=spf1 include:autosend.com -all
</code></pre>Replace <code>autosend.com</code> with your actual email service provider’s sending domain.2. Configure DKIMDKIM (DomainKeys Identified Mail) adds a digital signature to your emails.Example DKIM DNS record:<pre><code>v=DKIM1; k=rsa; p=MIIBIjANBgkqhk...
</code></pre>Your ESP (like AutoSend) provides this key. Add it to your DNS as a TXT record (usually under a selector like <code>default._domainkey.yourdomain.com</code>).3. Configure DMARCDMARC enforces alignment between SPF and DKIM. It also tells receiving servers what to do when emails fail authentication.Example DMARC DNS record:<pre><code>v=DMARC1; p=quarantine; rua=mailto:dmarc-reports@yourdomain.com; ruf=mailto:dmarc-failures@yourdomain.com; sp=none; adkim=s; aspf=s
</code></pre>Make sure your policy (<code>p=</code>) is set to quarantine or reject. BIMI will not work if your DMARC policy is set to none.<h3>Step 2: Create and Host a BIMI-Compatible Logo</h3>Your logo must meet BIMI’s strict visual and technical requirements.Logo Requirements:<ul><li>Format: SVG Tiny Portable/Secure (SVG-P/S)</li><li>Shape: Square (1:1 aspect ratio)</li><li>No text or taglines</li><li>Transparent background</li><li>File size: Under 32 KB</li></ul>If your logo is not in SVG Tiny PS format, you can convert it using Adobe Illustrator or online tools like the <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://easydmarc.com/tools/bimi-logo-converter">BIMI Logo Generator</a>.Example file name:<pre><code class="language-bash">https://yourdomain.com/logo.svg
</code></pre>Host this logo on an HTTPS-secured URL without redirects.<h3>Step 3: Obtain a Verified Mark Certificate (VMC)</h3>To show a verified checkmark (especially in Gmail), you will need a VMC, a digital certificate proving that your organization owns the logo and trademark.How to get a VMC:<ol><li>Register your logo as a trademark with an official authority such as USPTO or EUIPO. This is required before applying for a VMC.</li><li>Buy a VMC from a trusted certificate authority:<ul><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://www.entrust.com/">Entrust</a></li><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://www.digicert.com/">DigiCert</a></li></ul></li><li>Provide your trademark details, logo file, and proof of domain control during verification.</li></ol>The verification process usually takes 5 to 15 business days. Once approved, you will receive a <code>.pem</code> file that links your domain to your verified brand logo.<h3>Step 4: Publish the BIMI DNS Record</h3>After you have your logo and VMC, publish your BIMI record in DNS.Example TXT record:<pre><code>default._bimi.yourdomain.com IN TXT "v=BIMI1; l=https://yourdomain.com/logo.svg; a=https://yourdomain.com/vmc.pem"
</code></pre>Explanation:<ul><li><code>v=BIMI1</code> → version</li><li><code>l=</code> → location of your logo</li><li><code>a=</code> → location of your VMC file</li></ul>Note: The <code>a=</code> tag is optional for non-VMC implementations, but Gmail requires it for the verified checkmark.<h3>Step 5: Test Your BIMI Setup</h3>You can verify your BIMI configuration with these tools:<ul><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://www.bimigroup.org/bimi-generator/">BIMI Inspector</a></li><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://www.valimail.com/bimi-inspector/">Valimail BIMI Checker</a></li><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://mxtoolbox.com/BIMI.aspx">MXToolbox BIMI Lookup</a></li></ul>These tools check:<ul><li>DNS record syntax</li><li>SVG format</li><li>VMC validity</li><li>DMARC enforcement</li></ul>Once everything passes, your verified logo should appear in Gmail and other supported inboxes within a few days.<h2>Troubleshooting Common BIMI Issues</h2>Problem Cause Solution Logo not showing: <ul><li>Cause: DMARC policy set to <code>none</code> </li><li>Solution: Change it to <code>quarantine</code> or <code>reject</code> </li></ul>“No VMC found” error <ul><li>Cause: Missing or invalid <code>a=</code> tag </li><li>Solution: Add the correct VMC file URL </li></ul>Incorrect logo size<ul><li>Cause: SVG not compliant</li><li>Solution: Use SVG Tiny PS format </li></ul>No HTTPS<ul><li>Cause: Insecure logo hosting</li><li>Solution: Host logo and VMC over HTTPS</li></ul><h2>How Long Does It Take to Show?</h2>Once your BIMI record is published, it can take up to 7 days for mailbox providers to pick up and display the logo. Gmail may take a few extra days to cache the verification.<h2>The Business Value of BIMI</h2>Implementing BIMI is not just a technical task. It is a brand-building investment.<ul><li>Higher engagement: Users are more likely to open verified emails.</li><li>Reduced phishing risk: Impersonators cannot spoof your brand easily.</li><li>Consistent branding: Your logo is visible across inboxes, reinforcing recognition.</li><li>Improved deliverability: Providers trust domains that use BIMI.</li></ul><hr><h2>TL;DR</h2>To get a verified checkmark in Gmail and other inboxes:<ol><li>Set up SPF, DKIM, and DMARC with strict enforcement.</li><li>Create a square SVG Tiny PS logo and host it securely on HTTPS.</li><li>Register your logo as a trademark and obtain a Verified Mark Certificate (VMC).</li><li>Publish a BIMI DNS TXT record linking your logo and VMC.</li><li>Test and wait a few days for propagation.</li></ol>BIMI is becoming the modern trust signal for email, similar to the verified badge on social networks. By implementing it, you not only protect your brand but also show customers that you care about authenticity and security.If you are using AutoSend, BIMI setup is straightforward. AutoSend fully supports SPF, DKIM, and DMARC alignment, making it simple to authenticate and verify your domain.<hr><h2>Frequently Asked Questions (FAQ)</h2><h3>1. Does BIMI improve deliverability?</h3>Indirectly, yes. BIMI itself does not guarantee better inbox placement, but it relies on strong authentication. That improved trust and alignment positively impact your domain reputation and overall deliverability.<h3>2. How much does a Verified Mark Certificate (VMC) cost?</h3>A VMC usually costs between $900 and $1,500 per year, depending on the certificate authority. Some providers offer discounts for multi-year subscriptions.<h3>3. Can startups use BIMI without a trademark?</h3>Not if you want the verified checkmark in Gmail. Gmail requires a VMC, and a VMC requires a registered trademark. However, you can still implement BIMI without a VMC to display your logo in clients that support it without verification (such as Yahoo Mail).<h3>4. How long does it take to get verified after publishing BIMI?</h3>After publishing your BIMI DNS record and passing authentication checks, it usually takes 3 to 7 days for the logo and verified checkmark to appear in supported inboxes.<h3>5. What happens if my DMARC policy is set to “none”?</h3>BIMI will not activate. You must change your DMARC policy to quarantine or reject for BIMI to work.<h3>6. Do I need a separate BIMI record for subdomains?</h3>Yes, if you send emails from multiple subdomains, each subdomain should have its own BIMI record and logo configuration.<h3>7. Is BIMI supported in Outlook or Microsoft 365?</h3>Not yet. Microsoft has not implemented BIMI as of now, but it may support it in the future as adoption grows.

When you open an email from Apple or Google, you might notice a small blue checkmark or the brand’s official logo next to the sender’s name. That tiny icon is not decorative. It is a sign of verified authenticity, powered by BIMI (Brand Indicators for Message Identification).Implementing BIMI is one of the most effective ways to increase trust, visibility, and open rates for your transactional and marketing emails. This guide explains everything you need to know from DNS setup to logo requirements and verification so you can earn that verified checkmark for your brand.What Is BIMI?BIMI is an email authentication standard that allows brands to display their official logo next to their emails in recipients’ inboxes.It builds on top of DMARC, SPF, and DKIM, ensuring that only legitimate senders can use a company’s logo.In short:SPF verifies the sending IP address.DKIM verifies that the message content has not been tampered with.DMARC enforces alignment and policy.BIMI adds a visual trust layer using your brand logo.Why BIMI MattersBoosts Trust: The verified logo signals authenticity and reduces phishing risk.Increases Open Rates: Emails with visible brand logos stand out in crowded inboxes.Enhances Brand Recognition: Your logo appears alongside your sender name across supported email clients.Supports Deliverability: BIMI indirectly improves domain reputation through strong authentication.Email Clients That Support BIMIBIMI is still growing in adoption but is already supported by major inbox providers.Currently supported by:Gmail (requires a Verified Mark Certificate)Yahoo MailApple Mail (macOS and iOS 16 and above)FastmailAOL MailStep-by-Step Guide to Getting the Verified Checkmark with BIMIThere are four main steps to implement BIMI correctly:Set up email authenticationCreate and host your logo in the right formatObtain a Verified Mark Certificate (VMC)Publish your BIMI DNS recordLet’s go through each step in detail.Step 1: Set Up Email Authentication (SPF, DKIM, and DMARC)BIMI works only if your email domain passes all authentication checks.1. Configure SPFSPF (Sender Policy Framework) ensures that only your authorized servers can send emails on behalf of your domain.Example DNS TXT record:v=spf1 include:autosend.com -all
Replace autosend.com with your actual email service provider’s sending domain.2. Configure DKIMDKIM (DomainKeys Identified Mail) adds a digital signature to your emails.Example DKIM DNS record:v=DKIM1; k=rsa; p=MIIBIjANBgkqhk...
Your ESP (like AutoSend) provides this key.Add it to your DNS as a TXT record (usually under a selector like default._domainkey.yourdomain.com).3. Configure DMARCDMARC enforces alignment between SPF and DKIM. It also tells receiving servers what to do when emails fail authentication.Example DMARC DNS record:v=DMARC1; p=quarantine; rua=mailto:dmarc-reports@yourdomain.com; ruf=mailto:dmarc-failures@yourdomain.com; sp=none; adkim=s; aspf=s
Make sure your policy (p=) is set to quarantine or reject. BIMI will not work if your DMARC policy is set to none.Step 2: Create and Host a BIMI-Compatible LogoYour logo must meet BIMI’s strict visual and technical requirements.Logo Requirements:Format: SVG Tiny Portable/Secure (SVG-P/S)Shape: Square (1:1 aspect ratio)No text or taglinesTransparent backgroundFile size: Under 32 KBIf your logo is not in SVG Tiny PS format, you can convert it using Adobe Illustrator or online tools like the BIMI Logo Generator.Example file name:https://yourdomain.com/logo.svg
Host this logo on an HTTPS-secured URL without redirects.Step 3: Obtain a Verified Mark Certificate (VMC)To show a verified checkmark (especially in Gmail), you will need a VMC, a digital certificate proving that your organization owns the logo and trademark.How to get a VMC:Register your logo as a trademark with an official authority such as USPTO or EUIPO. This is required before applying for a VMC.Buy a VMC from a trusted certificate authority:EntrustDigiCertProvide your trademark details, logo file, and proof of domain control during verification.The verification process usually takes 5 to 15 business days. Once approved, you will receive a .pem file that links your domain to your verified brand logo.Step 4: Publish the BIMI DNS RecordAfter you have your logo and VMC, publish your BIMI record in DNS.Example TXT record:default._bimi.yourdomain.com IN TXT "v=BIMI1; l=https://yourdomain.com/logo.svg; a=https://yourdomain.com/vmc.pem"
Explanation:v=BIMI1 → versionl= → location of your logoa= → location of your VMC fileNote: The a= tag is optional for non-VMC implementations, but Gmail requires it for the verified checkmark.Step 5: Test Your BIMI SetupYou can verify your BIMI configuration with these tools:BIMI InspectorValimail BIMI CheckerMXToolbox BIMI LookupThese tools check:DNS record syntaxSVG formatVMC validityDMARC enforcementOnce everything passes, your verified logo should appear in Gmail and other supported inboxes within a few days.Troubleshooting Common BIMI IssuesProblem Cause Solution Logo not showing: Cause: DMARC policy set to none Solution: Change it to quarantine or reject “No VMC found” error Cause: Missing or invalid a= tag Solution: Add the correct VMC file URL Incorrect logo sizeCause: SVG not compliantSolution: Use SVG Tiny PS format No HTTPSCause: Insecure logo hostingSolution: Host logo and VMC over HTTPSHow Long Does It Take to Show?Once your BIMI record is published, it can take up to 7 days for mailbox providers to pick up and display the logo. Gmail may take a few extra days to cache the verification.The Business Value of BIMIImplementing BIMI is not just a technical task. It is a brand-building investment.Higher engagement: Users are more likely to open verified emails.Reduced phishing risk: Impersonators cannot spoof your brand easily.Consistent branding: Your logo is visible across inboxes, reinforcing recognition.Improved deliverability: Providers trust domains that use BIMI.TL;DRTo get a verified checkmark in Gmail and other inboxes:Set up SPF, DKIM, and DMARC with strict enforcement.Create a square SVG Tiny PS logo and host it securely on HTTPS.Register your logo as a trademark and obtain a Verified Mark Certificate (VMC).Publish a BIMI DNS TXT record linking your logo and VMC.Test and wait a few days for propagation.BIMI is becoming the modern trust signal for email, similar to the verified badge on social networks.By implementing it, you not only protect your brand but also show customers that you care about authenticity and security.If you are using AutoSend, BIMI setup is straightforward. AutoSend fully supports SPF, DKIM, and DMARC alignment, making it simple to authenticate and verify your domain.Frequently Asked Questions (FAQ)1. Does BIMI improve deliverability?Indirectly, yes. BIMI itself does not guarantee better inbox placement, but it relies on strong authentication. That improved trust and alignment positively impact your domain reputation and overall deliverability.2. How much does a Verified Mark Certificate (VMC) cost?A VMC usually costs between $900 and $1,500 per year, depending on the certificate authority. Some providers offer discounts for multi-year subscriptions.3. Can startups use BIMI without a trademark?Not if you want the verified checkmark in Gmail. Gmail requires a VMC, and a VMC requires a registered trademark. However, you can still implement BIMI without a VMC to display your logo in clients that support it without verification (such as Yahoo Mail).4. How long does it take to get verified after publishing BIMI?After publishing your BIMI DNS record and passing authentication checks, it usually takes 3 to 7 days for the logo and verified checkmark to appear in supported inboxes.5. What happens if my DMARC policy is set to “none”?BIMI will not activate. You must change your DMARC policy to quarantine or reject for BIMI to work.6. Do I need a separate BIMI record for subdomains?Yes, if you send emails from multiple subdomains, each subdomain should have its own BIMI record and logo configuration.7. Is BIMI supported in Outlook or Microsoft 365?Not yet. Microsoft has not implemented BIMI as of now, but it may support it in the future as adoption grows.

Learn how to set up BIMI to display your verified logo and checkmark in Gmail to boost trust and email deliverability.

How to Get a Verified Checkmark in Gmail with BIMI

When you start using AutoSend to send <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/transactional-emails">transactional emails</a>, you’re likely using a freshly connected domain or subdomain. That domain might be perfectly configured with verified DNS, working SPF, DKIM, and DMARC. But to mailbox providers like Gmail or Outlook, it’s brand new. They don’t yet know your sending behavior or your engagement quality.If you start sending thousands of password resets or verification emails right away, filters may flag your messages as suspicious. This is where domain warm-up comes in.<h2>What is domain warm-up?</h2>Domain warm-up is the process of gradually increasing the volume of emails you send through a new domain or IP.The goal is to show mailbox providers that you’re a legitimate sender who sends to real, engaged users and not a spammer blasting to thousands of unverified addresses.Think of it like training mode for your domain. Every email you send builds reputation, and with each positive signal (like opens, clicks, or successful deliveries), your domain earns trust.<h2>Why warm-up matters when you start using AutoSend</h2>When you connect a new domain in AutoSend, the system authenticates it automatically with <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/spf-sender-policy-framework">SPF</a>, <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/dkim-domainkeys-identified-mail">DKIM</a>, and <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/dmarc-domain-based-message-authentication-reporting-conformance">DMARC</a> settings. Technically, you’re ready to send.But reputation is not built overnight. Without a warm-up phase:<ul><li>Your first few campaigns might land in spam or promotions tabs.</li><li>You could experience slow delivery or throttling by major inboxes.</li><li>Your sender reputation could drop before it even starts.</li></ul>Warming up allows AutoSend’s sending infrastructure and your domain to build a positive reputation together. It’s how you establish consistent inbox placement from day one.<h2>Before you start warming up</h2>Make sure these basics are covered before sending your first email:1. Use a dedicated subdomain for transactional emails Instead of sending from your root domain, use something like <code>notify.yourdomain.com</code>. This separates transactional emails from marketing traffic and keeps your main domain reputation safe.2. Verify your domain in AutoSend Go to your AutoSend dashboard and complete domain verification. This ensures your SPF and DKIM records are valid and the domain is ready for sending.3. Send only to real users If you already have active customers or verified users, start with them. Don’t test with random or inactive addresses. High bounces in the first week can severely hurt your reputation.<h2>Step-by-step warm-up plan for AutoSend users</h2><h3>Week 1: Start small and consistent</h3>Send around 20 to 50 transactional emails per day. Examples: sign-up confirmations, test password resets, or account alerts.AutoSend will automatically log each email’s delivery, bounce, and open rate. Keep an eye on these metrics from your dashboard.<h3>Week 2: Slowly increase the volume</h3>If your first week looks healthy (no major bounces or spam complaints), double your daily sending volume. Maintain the same schedule. Sending consistently every day is more important than sending large batches.<h3>Week 3–4: Ramp up to normal usage</h3>You can now start sending more real transactional traffic. Increase gradually by 25–30 percent every few days. Watch your logs in AutoSend; if you notice rising bounce or delay rates, hold the volume steady until things stabilize.<h3>After a month: Reach steady state</h3>Once you’ve reached your normal email volume and maintain stable deliverability, your domain is officially “warmed up.” From here on, consistent performance and low bounce rates will keep your reputation strong.<h2>What AutoSend tracks to help during warm-up</h2>AutoSend provides detailed logs and metrics that are essential during warm-up:<ul><li>Delivery rate – How many emails successfully reach the inbox.</li><li>Bounce reports – Identify invalid addresses early.</li><li>Latency – How fast messages are accepted by recipient servers.</li><li>Spam or complaint signals – See if users flag your messages.</li></ul>You can access all these insights directly in your AutoSend dashboard.<h2>Common mistakes to avoid</h2><ul><li>Sending too much, too soon: The most common mistake is sending large volumes right after connecting your domain to AutoSend. When a brand-new domain suddenly starts sending thousands of emails, mailbox providers interpret that as suspicious behavior. It resembles what spammers do — appear out of nowhere and flood inboxes. Start small, send consistently, and increase volume gradually. This signals stability and helps mailbox algorithms learn to trust your sending pattern.</li><li>Testing with fake or inactive email addresses: It might be tempting to bulk-test your setup using random or made-up addresses, but that’s a fast way to ruin your domain’s reputation. Every bounce or invalid recipient negatively affects your trust score. Instead, test with verified accounts — your own team, colleagues, or users who actually exist. In AutoSend, you can track every delivery and bounce in your logs, so you don’t need to risk fake tests.</li><li>Ignoring soft bounces and temporary errors: Soft bounces often get dismissed as “minor” issues, but they’re valuable signals. They usually indicate that the receiving server is temporarily limiting your volume or delaying acceptance until it trusts you more. If you keep pushing the same volume without addressing it, providers may start blocking you completely. Watch for patterns in your AutoSend delivery logs. If you see repeated soft bounces, slow your sending rate or pause the ramp-up until things stabilize.</li><li>Mixing marketing and transactional messages: During warm-up, focus only on true transactional emails — password resets, account verifications, or receipts. Mixing promotional content like discounts or product updates confuses spam filters and can damage your domain’s reputation before it’s even established. Always send marketing campaigns from a separate subdomain, for example, <code>updates.yourdomain.com</code>, while keeping transactional traffic on <code>notifications.yourdomain.com</code>. AutoSend supports multiple verified domains and subdomains, making this easy to manage.</li><li>Not checking AutoSend logs or monitoring metrics: One of the biggest advantages of AutoSend is visibility — you can see exactly what’s happening with every message you send. Ignoring this data during warm-up is like flying blind. Your logs show delivery success, bounces, latency, and user engagement. Checking them regularly helps you identify potential issues early. If you notice unusual delays, high bounces, or authentication errors, it’s a sign to pause and correct the setup before scaling further.</li><li>Stopping activity too soon: Some users complete their warm-up successfully and then stop sending emails for several weeks. That can actually cause your domain reputation to cool down again. Mailbox providers value consistent patterns, so when you stop sending, your “trust history” begins to fade. If you anticipate downtime, keep a minimal amount of activity running — even a few test emails every few days through AutoSend is enough to maintain domain freshness.</li></ul><h2>How long should warm-up take?</h2>For most AutoSend users, it takes around 2 to 3 weeks to reach full volume safely. Smaller teams or products with lower email traffic can complete it in less time. If your monthly sending volume is less than 10,000 emails then it should be 1 to 2 weeks.The key is not speed but consistency. A slow and steady ramp-up gives mailbox providers the confidence they need to treat your messages as trusted communication.<h2>Maintaining your sender reputation</h2>Once your domain is fully warmed up:<ul><li>Keep sending regularly — inactivity can reset reputation.</li><li>Monitor your <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/bounce-rate">bounce rate</a> weekly.</li><li>Use AutoSend’s logs to ensure your authentication remains valid.</li><li>Avoid sudden spikes in email volume.</li></ul>Treat your domain’s reputation like uptime monitoring. It’s ongoing maintenance, not a one-time task.<hr>Warming up your domain is one of the most important things you can do when starting out with AutoSend or any other <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/email-service-provider-esp">email service provider</a>.It’s not complicated, just intentional. Start small, be consistent, and use the detailed logs AutoSend provides to monitor every stage. Within a few weeks, your emails will reach inboxes faster, avoid spam filters, and stay reliable — exactly what transactional emails are meant to do.You’ve read this far, so here’s a quick tip: encourage users to reply to your emails to boost your domain reputation.<hr><h2>Frequently Asked Questions</h2><h3>Do I need to warm up my domain after connecting it to AutoSend?</h3>Yes. Even if your domain is verified in AutoSend, mailbox providers don’t yet trust it. Warming up builds a positive reputation and prevents your emails from being flagged or delayed.<hr><h3>2. How long should I warm up before sending full volume?</h3>It usually takes around 3 to 4 weeks for most AutoSend users to reach steady-state volume. The exact time depends on your daily email traffic and engagement rates.<hr><h3>3. Should I use my main domain or a subdomain for transactional emails?</h3>Use a subdomain like <code>notifications.yourdomain.com</code>. AutoSend makes this easy to configure during domain setup. It isolates your transactional traffic from marketing or newsletter emails.<hr><h3>4. How can I monitor my progress during warm-up?</h3>Your AutoSend dashboard shows real-time logs for every email: delivery status, bounces, latency, and engagement metrics. You can use this data to track how your warm-up is progressing and adjust accordingly.<hr><h3>5. What happens if I send too many emails too quickly?</h3>Mailbox providers may throttle or block your messages, causing slow delivery or spam placement. It can also lower your domain reputation, making recovery harder later.<hr><h3>6. Can I warm up multiple domains in AutoSend?</h3>Yes. If you manage multiple products or environments, you can verify and warm up separate subdomains individually inside your AutoSend account. Each one will build its own reputation.<hr><h3>7. What if I stop sending emails for a few weeks after warming up?</h3>If your domain goes inactive for a long time, reputation may start to decay. When you resume, repeat a shorter warm-up phase by sending smaller volumes again for a few days.

When you start using AutoSend to send transactional emails, you’re likely using a freshly connected domain or subdomain. That domain might be perfectly configured with verified DNS, working SPF, DKIM, and DMARC. But to mailbox providers like Gmail or Outlook, it’s brand new. They don’t yet know your sending behavior or your engagement quality.If you start sending thousands of password resets or verification emails right away, filters may flag your messages as suspicious. This is where domain warm-up comes in.What is domain warm-up?Domain warm-up is the process of gradually increasing the volume of emails you send through a new domain or IP.The goal is to show mailbox providers that you’re a legitimate sender who sends to real, engaged users and not a spammer blasting to thousands of unverified addresses.Think of it like training mode for your domain. Every email you send builds reputation, and with each positive signal (like opens, clicks, or successful deliveries), your domain earns trust.Why warm-up matters when you start using AutoSendWhen you connect a new domain in AutoSend, the system authenticates it automatically with SPF, DKIM, and DMARC settings. Technically, you’re ready to send.But reputation is not built overnight. Without a warm-up phase:Your first few campaigns might land in spam or promotions tabs.You could experience slow delivery or throttling by major inboxes.Your sender reputation could drop before it even starts.Warming up allows AutoSend’s sending infrastructure and your domain to build a positive reputation together. It’s how you establish consistent inbox placement from day one.Before you start warming upMake sure these basics are covered before sending your first email:1. Use a dedicated subdomain for transactional emailsInstead of sending from your root domain, use something like notify.yourdomain.com. This separates transactional emails from marketing traffic and keeps your main domain reputation safe.2. Verify your domain in AutoSendGo to your AutoSend dashboard and complete domain verification. This ensures your SPF and DKIM records are valid and the domain is ready for sending.3. Send only to real usersIf you already have active customers or verified users, start with them. Don’t test with random or inactive addresses. High bounces in the first week can severely hurt your reputation.Step-by-step warm-up plan for AutoSend usersWeek 1: Start small and consistentSend around 20 to 50 transactional emails per day.Examples: sign-up confirmations, test password resets, or account alerts.AutoSend will automatically log each email’s delivery, bounce, and open rate. Keep an eye on these metrics from your dashboard.Week 2: Slowly increase the volumeIf your first week looks healthy (no major bounces or spam complaints), double your daily sending volume. Maintain the same schedule. Sending consistently every day is more important than sending large batches.Week 3–4: Ramp up to normal usageYou can now start sending more real transactional traffic.Increase gradually by 25–30 percent every few days. Watch your logs in AutoSend; if you notice rising bounce or delay rates, hold the volume steady until things stabilize.After a month: Reach steady stateOnce you’ve reached your normal email volume and maintain stable deliverability, your domain is officially “warmed up.” From here on, consistent performance and low bounce rates will keep your reputation strong.What AutoSend tracks to help during warm-upAutoSend provides detailed logs and metrics that are essential during warm-up:Delivery rate – How many emails successfully reach the inbox.Bounce reports – Identify invalid addresses early.Latency – How fast messages are accepted by recipient servers.Spam or complaint signals – See if users flag your messages.You can access all these insights directly in your AutoSend dashboard.Common mistakes to avoidSending too much, too soon: The most common mistake is sending large volumes right after connecting your domain to AutoSend. When a brand-new domain suddenly starts sending thousands of emails, mailbox providers interpret that as suspicious behavior. It resembles what spammers do — appear out of nowhere and flood inboxes. Start small, send consistently, and increase volume gradually. This signals stability and helps mailbox algorithms learn to trust your sending pattern.Testing with fake or inactive email addresses: It might be tempting to bulk-test your setup using random or made-up addresses, but that’s a fast way to ruin your domain’s reputation. Every bounce or invalid recipient negatively affects your trust score. Instead, test with verified accounts — your own team, colleagues, or users who actually exist. In AutoSend, you can track every delivery and bounce in your logs, so you don’t need to risk fake tests.Ignoring soft bounces and temporary errors: Soft bounces often get dismissed as “minor” issues, but they’re valuable signals. They usually indicate that the receiving server is temporarily limiting your volume or delaying acceptance until it trusts you more. If you keep pushing the same volume without addressing it, providers may start blocking you completely. Watch for patterns in your AutoSend delivery logs. If you see repeated soft bounces, slow your sending rate or pause the ramp-up until things stabilize.Mixing marketing and transactional messages: During warm-up, focus only on true transactional emails — password resets, account verifications, or receipts. Mixing promotional content like discounts or product updates confuses spam filters and can damage your domain’s reputation before it’s even established. Always send marketing campaigns from a separate subdomain, for example, updates.yourdomain.com, while keeping transactional traffic on notifications.yourdomain.com. AutoSend supports multiple verified domains and subdomains, making this easy to manage.Not checking AutoSend logs or monitoring metrics: One of the biggest advantages of AutoSend is visibility — you can see exactly what’s happening with every message you send. Ignoring this data during warm-up is like flying blind. Your logs show delivery success, bounces, latency, and user engagement. Checking them regularly helps you identify potential issues early. If you notice unusual delays, high bounces, or authentication errors, it’s a sign to pause and correct the setup before scaling further.Stopping activity too soon: Some users complete their warm-up successfully and then stop sending emails for several weeks. That can actually cause your domain reputation to cool down again. Mailbox providers value consistent patterns, so when you stop sending, your “trust history” begins to fade. If you anticipate downtime, keep a minimal amount of activity running — even a few test emails every few days through AutoSend is enough to maintain domain freshness.How long should warm-up take?For most AutoSend users, it takes around 2 to 3 weeks to reach full volume safely. Smaller teams or products with lower email traffic can complete it in less time. If your monthly sending volume is less than 10,000 emails then it should be 1 to 2 weeks.The key is not speed but consistency. A slow and steady ramp-up gives mailbox providers the confidence they need to treat your messages as trusted communication.Maintaining your sender reputationOnce your domain is fully warmed up:Keep sending regularly — inactivity can reset reputation.Monitor your bounce rate weekly.Use AutoSend’s logs to ensure your authentication remains valid.Avoid sudden spikes in email volume.Treat your domain’s reputation like uptime monitoring. It’s ongoing maintenance, not a one-time task.Warming up your domain is one of the most important things you can do when starting out with AutoSend or any other email service provider.It’s not complicated, just intentional. Start small, be consistent, and use the detailed logs AutoSend provides to monitor every stage. Within a few weeks, your emails will reach inboxes faster, avoid spam filters, and stay reliable — exactly what transactional emails are meant to do.You’ve read this far, so here’s a quick tip: encourage users to reply to your emails to boost your domain reputation.Frequently Asked QuestionsDo I need to warm up my domain after connecting it to AutoSend?Yes. Even if your domain is verified in AutoSend, mailbox providers don’t yet trust it. Warming up builds a positive reputation and prevents your emails from being flagged or delayed.2. How long should I warm up before sending full volume?It usually takes around 3 to 4 weeks for most AutoSend users to reach steady-state volume. The exact time depends on your daily email traffic and engagement rates.3. Should I use my main domain or a subdomain for transactional emails?Use a subdomain like notifications.yourdomain.com. AutoSend makes this easy to configure during domain setup. It isolates your transactional traffic from marketing or newsletter emails.4. How can I monitor my progress during warm-up?Your AutoSend dashboard shows real-time logs for every email: delivery status, bounces, latency, and engagement metrics. You can use this data to track how your warm-up is progressing and adjust accordingly.5. What happens if I send too many emails too quickly?Mailbox providers may throttle or block your messages, causing slow delivery or spam placement. It can also lower your domain reputation, making recovery harder later.6. Can I warm up multiple domains in AutoSend?Yes. If you manage multiple products or environments, you can verify and warm up separate subdomains individually inside your AutoSend account. Each one will build its own reputation.7. What if I stop sending emails for a few weeks after warming up?If your domain goes inactive for a long time, reputation may start to decay. When you resume, repeat a shorter warm-up phase by sending smaller volumes again for a few days.

Learn how to warm up a new domain for transactional emails with this step-by-step guide. Improve deliverability, build reputation, and avoid spam filters.

How to Warm Up a New Domain for Transactional Emails

You build a great product, craft a thoughtful message, hit send... and then your user says, “I didn’t get the email.” So you check your logs, everything looks fine, but the message is sitting quietly in their spam folder. Oops, embarrassing!This is one of the most frustrating parts of running an app or sending transactional emails. The good news? It’s almost always fixable once you understand what’s going wrong.Let’s unpack why emails go to spam and how you can keep yours landing safely in the inbox.<h2>You haven’t set up proper email authentication</h2>This is the number one reason your emails end up in spam.If your domain isn’t authenticated, email providers like Gmail or Outlook can’t confirm the message is really coming from you. So, to protect users, they flag it as suspicious.Set up three essential DNS records:<ul><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/spf-sender-policy-framework">SPF</a> – lists the servers allowed to send emails for your domain.</li><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/dkim-domainkeys-identified-mail">DKIM</a> – adds a digital signature to prove the email wasn’t modified.</li><li><a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/glossary/dmarc-domain-based-message-authentication-reporting-conformance">DMARC</a> – tells providers what to do when an email fails SPF or DKIM checks.</li></ul>Once you configure these correctly, you’ll see a noticeable improvement in inbox placement. Tools like <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://www.mail-tester.com/">Mail-Tester</a>, <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://mxtoolbox.com/">MXToolbox</a>, or <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://dmarcian.com/">DMARCian</a> can help verify your setup.<h2>Your sending domain or IP has a poor reputation</h2>Every domain and IP has a reputation score that mailbox providers use to decide where your emails go. If too many of your messages get flagged, bounced, or ignored, your reputation drops, and your next emails are more likely to be filtered as spam.Common causes include:<ul><li>Sending large batches too quickly</li><li>Using shared IPs with other senders who spam</li><li>Getting high bounce or complaint rates</li></ul>To fix this:<ul><li>Warm up new domains gradually instead of blasting thousands of emails on day one.</li><li>Use dedicated IPs if you send high volume.</li><li>Keep your bounce rate below 2% and complaint rate below 0.1%.</li></ul>Think of your sender reputation like a credit score. Consistency, trust, and history matter more than speed.<h2>Your email content looks spammy</h2>Spam filters scan the content of your emails before they reach the inbox. Even if your authentication is perfect, your copy and formatting can still trigger a filter.Here’s what to watch out for:<ul><li>Overuse of “FREE,” “LIMITED TIME,” or “CLICK NOW.”</li><li>Too many images with little text.</li><li>Broken HTML or messy inline styles.</li><li>No plain text version of the email.</li><li>Missing unsubscribe link in marketing emails.</li></ul>Keep your design simple and your tone natural. Write like you’re talking to a person, not pitching a crowd. Always include a clear sender name, recognizable address, and valid contact info.Pro tip: Before sending a campaign, run it through a spam-check tool to see how filters interpret your content.<h2>You’re sending from a new or cold domain</h2>If your domain is brand new or has never sent emails before, providers don’t trust it yet. That’s normal.Start slow. Send small batches to verified or internal addresses, build up a positive history, and monitor engagement. This process is known as <a target="_blank" rel="noopener noreferrer" class="break-all link-break text-gray-500 hover:underline" href="https://autosend.com/blog/how-to-warm-up-a-new-domain-for-transactional-emails">domain warming</a>.You can also use a subdomain for your email traffic, like <code>mail.yourdomain.com</code> or <code>notifications.yourdomain.com</code>. This keeps your main domain safe if something goes wrong.Remember, reputation builds over time. The key is steady, consistent sending behavior.<h2>You’re not monitoring your delivery performance</h2>Email deliverability isn’t a one-time setup. It’s something you have to monitor continuously.Keep an eye on:<ul><li>Bounce logs: Which addresses are failing and why.</li><li>Open and click rates: Low engagement signals filters that your emails aren’t wanted.</li><li>Spam complaints: Even a small spike can affect your reputation.</li></ul>Most modern email platforms provide dashboards or webhook logs for this data. Reviewing them weekly helps you spot patterns before they become serious problems.If you’re sending through APIs or services like AutoSend, you can use Email Activity feature to track your delivery rate and fix authentication or content issues fast.<h2>You’re mixing transactional and promotional content</h2>This is an easy mistake to make. Transactional emails are system messages triggered by user actions (signup confirmations, password resets, invoices). Promotional emails are sent to promote something (updates, offers, new features).Mixing them confuses both users and spam filters. For example:<blockquote>“Your password has been reset successfully. Here’s a 30% discount on your next order.”</blockquote>That’s not a transactional email anymore. Keep them separate. Use different templates, sender names, or subdomains for each type.This clarity helps you stay compliant with laws like CAN-SPAM and improves overall inbox placement.<h2>You’re sending without user consent</h2>Even if you have the best infrastructure, sending emails to people who didn’t opt in is a fast track to the spam folder.Always collect consent before sending marketing messages. Use double opt-in where users confirm their subscription. Make it easy to unsubscribe or change preferences at any time.Trust is a long-term deliverability strategy. The fewer complaints you get, the stronger your domain reputation becomes.<h2>Test before you send</h2>Before sending anything to your full list, send test emails to a few different accounts (Gmail, Outlook, Yahoo) and check where they land.If they consistently show up in spam, inspect the headers and test against spam score tools. Small tweaks in authentication, copy, or formatting can often make the difference.<hr>Landing in the spam folder doesn’t mean your emails are doomed. It’s usually a sign that one or two technical or behavioral factors need attention.Start with authentication, check your domain reputation, simplify your content, and watch your logs. Over time, your inbox placement will improve and stay consistent.Good deliverability is not luck. It’s the result of clean setup, good habits, and trust built over time.

You build a great product, craft a thoughtful message, hit send... and then your user says, “I didn’t get the email.” So you check your logs, everything looks fine, but the message is sitting quietly in their spam folder. Oops, embarrassing!This is one of the most frustrating parts of running an app or sending transactional emails. The good news? It’s almost always fixable once you understand what’s going wrong.Let’s unpack why emails go to spam and how you can keep yours landing safely in the inbox.You haven’t set up proper email authenticationThis is the number one reason your emails end up in spam.If your domain isn’t authenticated, email providers like Gmail or Outlook can’t confirm the message is really coming from you. So, to protect users, they flag it as suspicious.Set up three essential DNS records:SPF – lists the servers allowed to send emails for your domain.DKIM – adds a digital signature to prove the email wasn’t modified.DMARC – tells providers what to do when an email fails SPF or DKIM checks.Once you configure these correctly, you’ll see a noticeable improvement in inbox placement. Tools like Mail-Tester, MXToolbox, or DMARCian can help verify your setup.Your sending domain or IP has a poor reputationEvery domain and IP has a reputation score that mailbox providers use to decide where your emails go. If too many of your messages get flagged, bounced, or ignored, your reputation drops, and your next emails are more likely to be filtered as spam.Common causes include:Sending large batches too quicklyUsing shared IPs with other senders who spamGetting high bounce or complaint ratesTo fix this:Warm up new domains gradually instead of blasting thousands of emails on day one.Use dedicated IPs if you send high volume.Keep your bounce rate below 2% and complaint rate below 0.1%.Think of your sender reputation like a credit score. Consistency, trust, and history matter more than speed.Your email content looks spammySpam filters scan the content of your emails before they reach the inbox. Even if your authentication is perfect, your copy and formatting can still trigger a filter.Here’s what to watch out for:Overuse of “FREE,” “LIMITED TIME,” or “CLICK NOW.”Too many images with little text.Broken HTML or messy inline styles.No plain text version of the email.Missing unsubscribe link in marketing emails.Keep your design simple and your tone natural. Write like you’re talking to a person, not pitching a crowd. Always include a clear sender name, recognizable address, and valid contact info.Pro tip: Before sending a campaign, run it through a spam-check tool to see how filters interpret your content.You’re sending from a new or cold domainIf your domain is brand new or has never sent emails before, providers don’t trust it yet. That’s normal.Start slow. Send small batches to verified or internal addresses, build up a positive history, and monitor engagement. This process is known as domain warming.You can also use a subdomain for your email traffic, like mail.yourdomain.com or notifications.yourdomain.com. This keeps your main domain safe if something goes wrong.Remember, reputation builds over time. The key is steady, consistent sending behavior.You’re not monitoring your delivery performanceEmail deliverability isn’t a one-time setup. It’s something you have to monitor continuously.Keep an eye on:Bounce logs: Which addresses are failing and why.Open and click rates: Low engagement signals filters that your emails aren’t wanted.Spam complaints: Even a small spike can affect your reputation.Most modern email platforms provide dashboards or webhook logs for this data. Reviewing them weekly helps you spot patterns before they become serious problems.If you’re sending through APIs or services like AutoSend, you can use Email Activity feature to track your delivery rate and fix authentication or content issues fast.You’re mixing transactional and promotional contentThis is an easy mistake to make. Transactional emails are system messages triggered by user actions (signup confirmations, password resets, invoices). Promotional emails are sent to promote something (updates, offers, new features).Mixing them confuses both users and spam filters. For example:“Your password has been reset successfully. Here’s a 30% discount on your next order.”That’s not a transactional email anymore. Keep them separate. Use different templates, sender names, or subdomains for each type.This clarity helps you stay compliant with laws like CAN-SPAM and improves overall inbox placement.You’re sending without user consentEven if you have the best infrastructure, sending emails to people who didn’t opt in is a fast track to the spam folder.Always collect consent before sending marketing messages. Use double opt-in where users confirm their subscription. Make it easy to unsubscribe or change preferences at any time.Trust is a long-term deliverability strategy. The fewer complaints you get, the stronger your domain reputation becomes.Test before you sendBefore sending anything to your full list, send test emails to a few different accounts (Gmail, Outlook, Yahoo) and check where they land.If they consistently show up in spam, inspect the headers and test against spam score tools. Small tweaks in authentication, copy, or formatting can often make the difference.Landing in the spam folder doesn’t mean your emails are doomed. It’s usually a sign that one or two technical or behavioral factors need attention.Start with authentication, check your domain reputation, simplify your content, and watch your logs. Over time, your inbox placement will improve and stay consistent.Good deliverability is not luck. It’s the result of clean setup, good habits, and trust built over time.

The email blog

Stories, strategies, and insights for sending better emails.