Glossary
Catch-all email
A catch-all email setup accepts mail sent to any address at a domain, even addresses that don't exist. Because the server says yes to everything, verification tools can't confirm whether a specific mailbox is real and label it catch-all or risky.
What Is Catch-All Email?
In short Companies turn on catch-all so mail with a typo, or sent to a former employee, still reaches someone.
Google Workspace, for example, has a routing setting that sends misaddressed mail to one chosen user or group. Separately, RFC 5321 lets any server accept a recipient during the SMTP conversation and report problems later, which looks the same from outside.
It breaks the mailbox check. A verifier asks the server whether it accepts [email protected] and gets yes. It asks about a random string at the same domain and also gets yes. So the result is catch-all, not valid. Some of those addresses are real, and others land in a shared inbox nobody reads or bounce later.
Catch-All Email Example
Example: a list of 1,000 contacts verifies as 700 valid, 80 invalid and 220 catch-all. The team sends the 700 first. It then sends 50 catch-alls from a single mailbox, sees 1 bounce (2%) and sends the rest at the same slow pace, ready to stop if bounces climb.
Catch-All Email in Practice
Teams handle catch-alls separately. Send to verified addresses first, then send to catch-alls in small batches from one mailbox, watch bounces and drop any domain that starts rejecting mail.
FAQ
What is a catch-all email address?
An address on a domain whose mail server accepts mail for any address, real or not. Mail to a nonexistent address at that domain doesn't bounce right away.
Should you send to catch-all emails?
Carefully. Many are real, but some bounce later or go to an unread shared inbox. Send to verified addresses first, then test catch-alls in small batches and stop if bounces rise.
Why can't email verification confirm catch-all addresses?
Because the server answers yes for every address at the domain, including made-up ones. The SMTP check has nothing to tell a real mailbox apart from a fake one.
How do you know if a domain is catch-all?
Ask its mail server whether it accepts a random address that can't exist, such as a long string of letters. If the server accepts it, the domain is catch-all. Verification tools run this test for you.
Do This in Ken
Do This in Ken
Ken Search labels catch-all addresses separately from valid ones and runs them through a dedicated catch-all check. You pay 1 credit only for an email that comes back valid.
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- Ken Search
- Open in Ken
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The new Ken opens to the waiting list in batches.
Related
- GTM Glossary
Every GTM term, grouped by topic.
- Email verification
- Email bounce rate
- MX record
- Waterfall enrichment
- Sender reputation
- Ken
Sources
| Source | Checked |
|---|---|
| RFC 5321: Simple Mail Transfer Protocol | |
| Google Workspace Admin Help: Get misaddressed email in a catch-all mailbox |
Changelog
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