Invalid Emails

Email addresses that don't exist or are incorrectly formatted, causing permanent delivery failures.

What are Invalid Emails?

Invalid emails are addresses that cannot accept mail because they’re either incorrectly formatted or don’t exist. They’re one of the most common causes of Bounced Emails. Invalid emails usually enter your system through user typos, fake signups, or outdated contact lists.

Why it matters

Sending to invalid emails damages your Deliverability. Each failed attempt is logged as a hard bounce, which mailbox providers interpret as a sign of poor list management. Over time, this increases the likelihood of your emails being filtered as spam or blocked altogether.

How it works

When you send an email, the recipient's mail server checks whether the address exists. If it doesn't, it returns a permanent SMTP error code (like "550 – User not found"). Your Email Service Provider (ESP), such as AutoSend, then adds the address to the Suppression List so you don't send to it again.

Examples

“gmial.com” instead of “gmail.com” typed during signup.
A company email address that stops working after an employee leaves.
Fake addresses like “[email protected]” entered to bypass signup forms.

Best practices

Use real-time validation tools at signup to block invalid addresses.
Encourage double opt-in so users confirm their emails.
Regularly clean your database to remove stale or invalid entries.

FAQs

How do invalid emails get into my list?
Most come from user typos (like “gmal.com”) or bots filling out forms. They can also result from purchased lists, which often contain outdated or fake addresses.

Are invalid emails the same as role-based emails?
No. Role-based emails like “[email protected]” are valid but risky because they often forward to multiple people. Invalid emails simply don’t exist.

What happens if I keep sending to invalid emails?
Mailbox providers will flag your domain as careless, reducing your inbox placement. High levels of invalid sends can even get your IP blocked.