Catch-all domain

Some companies configure their mail server to accept every message sent to their domain, either to avoid losing mail sent to a misspelled address or as a side effect of security filtering. For a sender, this hides the answer email verification depends on: the server says yes to name.surname@ and to random-string@ alike, and only later, if at all, does a message bounce.

Verifiers report these addresses as catch-all, or accept-all, rather than valid. Sending to them is a gamble with your bounce rate and sender reputation, and the risk grows with volume. Common choices are to skip catch-all addresses entirely, to send to them only from a separate domain in small numbers. Whichever you choose, it should be a deliberate rule, recorded with each skipped lead, rather than chance.