A catch-all email address is a domain setting that accepts mail sent to any name at that domain and delivers it to one inbox. If yourdomain.com has a catch-all, a message to anything@yourdomain.com arrives even though nobody created that address beforehand — and so does a message to a name that was mistyped or made up on the spot.
How catch-all works
An email address has two parts: the local part before the @ and the domain after it. To deliver a message, the sending server looks up the domain's MX records in DNS, connects to the server those records name, and tells it which recipient the message is for.
A typical mail server checks the local part against its list of mailboxes. If the name does not exist, it rejects that recipient and the sender gets a bounce. A server with catch-all enabled skips that rejection: it accepts any local part and files the message into one designated inbox.
Catch-all is a behaviour of the receiving server, not a DNS record. The MX records decide which server receives mail for the domain, so a catch-all only works when they point to a host that offers it.
Catch-all vs forwarding vs aliases
An alias is an extra address attached to an existing mailbox, such as sales@ delivering into the same inbox as you@. Aliases are created one at a time; mail to a name you have not set up still bounces.
Forwarding relays each message to another address as soon as it arrives, often without keeping a copy at the forwarding host. It changes where mail ends up, but on its own it does not make unknown names valid.
A catch-all accepts every name with no per-address setup. Some hosts combine the ideas, for example a catch-all that forwards elsewhere, but the defining feature of a catch-all is that the set of working addresses is open-ended.
Good uses for a catch-all address
Per-site sign-up addresses. Give each service its own address, such as bookshop@yourdomain.com. You do not have to create it first, and you can filter that one name later without touching anything else.
Testing. Developers and QA teams can use a fresh address for every test run, such as signup-test-0412@yourdomain.com, and still receive the confirmation email or one-time code. An automated test can fetch that code through the temp mail API.
Seeing who shares your address. If spam starts arriving at an address you gave to only one company, you know where it came from.
Temporary addresses on a domain you control. Public temp mail is convenient, but the domains are shared and on many services anyone who knows an address can open its inbox. A catch-all on your own domain gives you the same throwaway addresses while keeping the inbox private — the idea behind custom temp mail.
Trade-offs: spam and silent typos
More spam. Spammers send to common or random names at a domain — info@, admin@, strings of letters — in the hope that one exists. A normal server rejects most of them; a catch-all accepts them all, so they collect in your inbox.
No bounces for mistakes. When someone mistypes a real person's address, the sender does not see an error. The message lands in the catch-all inbox instead, and the sender assumes it reached the right person.
To keep this manageable, put the catch-all on a dedicated secondary domain rather than the domain you use for real correspondence, filter or delete by recipient name, and stop using an address once it starts attracting junk.
How to set up a catch-all inbox
At a full email host. Many business email providers support catch-all delivery. Google Workspace has a routing setting in its admin console that can send mail for unknown addresses to a chosen mailbox, and Microsoft 365 can be configured to route mail for unknown addresses to a chosen mailbox (it takes mail-flow configuration, not a single switch). Menu names change over time, so follow the provider's current admin documentation.
With Free Domain Mail. Add a domain you own, then publish two records at the DNS provider that is authoritative for it: one TXT record that proves ownership and one MX record pointing to mx.freedomainmail.com. Once the records are verified, every address at the domain receives mail immediately; there is nothing to create per address. Messages are kept for 30 days and can be read on the web or fetched through the API.
Free Domain Mail is receive-only: it never sends or forwards mail, and there is no IMAP, SMTP or POP3 access. Because changing the MX moves all incoming mail for the domain, use a domain that does not already receive mail you depend on. The setup guide walks through each record.
Type Name / Host Value
MX @ mx.freedomainmail.com
TXT _maildock-verify maildock-verify=… (shown in the app)Check that it works
Run an MX lookup for the domain. The answer should list only the host you intend to receive mail — for Free Domain Mail, mx.freedomainmail.com. If the old records still appear, wait for their TTL to expire and check again.
Then send a message from an outside account to a name you have never used, such as random-check-73@yourdomain.com. If it arrives in the catch-all inbox, the setup is working. If the sender gets a bounce, the MX probably still points somewhere else.
dig +short MX yourdomain.com
# the answer should name mx.freedomainmail.comCommon mistakes to avoid
- Leaving MX records for two different providers in place. Senders can deliver to either host, so some mail ends up in an inbox you are not checking.
- Enabling catch-all on your main business domain, then drowning in spam to made-up names while typos of real colleagues' addresses stop bouncing.
- Expecting to reply from a receive-only catch-all. A receiving service only collects mail; replies have to come from a host that can send.
Frequently asked questions
What does catch-all mean in email?
It means the domain's mail server accepts messages for any address at the domain, including names that were never created, and delivers them to one inbox instead of bouncing them.
Is a catch-all email address bad for deliverability?
Not for mail you send. Catch-all is a receiving setting, so it does not change how other providers treat messages from your domain. The cost is on the receiving side: the inbox can attract spam sent to random names, and mistyped addresses no longer bounce.
Can I reply from a catch-all address?
It depends on the host. Some full email providers let you send as any address at the domain. Free Domain Mail is receive-only: it never sends or forwards mail, so replies need a separate sending service.
Do I need to create each address first?
No. That is the point of a catch-all: any name at the domain is accepted as soon as the domain's MX records point to a host with catch-all enabled.
Can I set up a catch-all on a domain I do not own?
No. A catch-all depends on the domain's MX records, so you need access to the domain's DNS settings.