Knowledge base
Catch-all addresses
Every address on the domain receives, including ones that have never been created. One switch closes it.
Details
- One switch per domain, under Accepted addresses in Settings → Domains. A domain you add arrives with it on, and the dialog that adds it says so, because a domain that receives at one address and silently refuses the rest is the surprise worth avoiding. Closing it is the deliberate act, and it is the same one switch.
- An alias comes into existence the moment mail arrives for it, so there is no list to maintain. The recording stops at 500 auto-created addresses per domain. Mail past that is still delivered, it is only the row that goes unwritten, which is what keeps a dictionary run from filling the list.
- An address becomes something you invent on the spot: oct-2026-signup@, that-conference@, netflix@.
- Plus-addressing works alongside it, so hello+receipts@ lands in hello@ with the tag still on the message.
- With it on, deleting an address only blocks it: the row stays in the list, turned off, because the next message to it would otherwise create it again and be delivered. Turn catch-all off first if you want the address gone entirely.
- It works the same on a subdomain as on an apex. Nothing has to be listed anywhere in advance and there is no ceiling on how many addresses a domain can receive at. Working out who a message belongs to is a lookup rather than a rule published somewhere, which is also why the 500 above bounds the list and never the delivery.