Catch-all email

Also called: Accept-all email, Catch-all domain, Accept-all domain.

A catch-all (or accept-all) domain is set up to accept mail for every address at that domain, whether or not a mailbox by that name exists. owner@, info@ and x7q2@ all get the same 250 accepted reply during the SMTP conversation defined in RFC 5321.

Verifiers detect it by asking the server about an address that can't possibly exist, such as a long random string. If the server accepts that too, its yes about the real address carries no information. The honest grade is unconfirmed: a maybe, never a yes.

Catch-all setups are common among small and local businesses, because routing every address to one inbox is the simplest way to make sure no customer email is lost. That means a list of plumbers, dentists or salons from Google Maps will usually contain a real share of catch-all domains.

The risks of sending to them are late bounces (the server accepts, then bounces after its own checks), mail that lands in an inbox nobody reads, and abandoned domains that keep accepting everything. The practical rule: prefer addresses the business published on its own website over pattern guesses, send catch-all addresses as a separate, smaller segment after your verified ones, and stop if that segment bounces noticeably more.

The most common mistake is a verifier or list vendor counting catch-all addresses as valid. It makes the valid rate look high and your bounce rate pays for it.

Example

A verifier checks office@smithplumbing.com and gets 250. It then checks zq81kd03@smithplumbing.com and also gets 250. The domain accepts everything, so the address is graded catch-all rather than valid, even though it may well be the owner's main inbox.

In Leadraft

Catch-all is its own grade, Accept-all. Exports include only Verified emails by default, Accept-all ones only if you choose, and each address shows the page it was found on. See the verification methodology.