A catch-all domain accepts mail for any address, even if it doesn’t exist. Learn why catch-all matters for email verification and bounces.
A catch-all email setup is when a domain is configured to accept emails sent to any address at that domain, even if the specific mailbox doesn’t exist. This is often done to avoid missing mis-typed emails or to centralize inbound routing.
Catch-all domains complicate email verification because an address can appear deliverable even if it isn’t assigned to a real person. SMTP checks may report acceptance while the mailbox is effectively a sink.
For list hygiene, catch-all results are usually labeled as “risky” rather than “valid.” The safest approach is to rely on engagement over time and to be cautious when adding catch-all addresses to large campaigns.