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Catch-All Mail Server

A catch-all mail server is a mail server that is designed to accept all messages sent to a specific domain. It will receive messages regardless of whether the email address is valid or not.

For example, say a business’s domain is Now, it could have many email addresses with that domain, for example,,, and

If the mail server is set up as a catch-all mail server, it will receive all messages sent to that domain no matter what the username. This means, apart from the email sent to the addresses above, it will also receive emails to wrong and invalid addresses. For example, it will receive sent to,, and any others.

Why Do Catch All Mail Servers Exist?

Businesses often implement catch-all email servers because they are then less likely to miss important messages. These messages can include emails from a potential partner, investor, or from loyal customers. Irrespective of who it’s from, the mail server will receive it. This is especially helpful where someone sends an important email but makes a mistake in the name. Despite this, the business will still receive the mail.

Initially, this was very helpful for businesses to prevent important emails from being lost. Using this method, the server would receive all mails, and the mailbox could be reviewed often to ensure that no important messages went missing.

There is a problem, though. Catch-all servers make it easier for spammers to bombard a mail server with unsolicited messages. As a result, most catch all mailboxes today receive too much spam which makes them functionally useless.

As a result, catch all mail servers present the following risks:

•    High bounce rate.
•    Low open rates.
•    Higher spam rates.


How Can I Determine If An Email Address Is On A Catchall Server?

To eliminate these risks, the question is whether a catch-all email address can be verified. This is important because sending mails to the catch-all mail servers can impact a marketer’s or business’s sender score. This, ultimately, results in their email deliverability to valid email addresses being negatively impacted.

So, the answer to the question is yes, it can be verified. There are a variety of tools and platforms that can help businesses to identify catch-all addresses. As a result, businesses can remove these emails from their email lists and keep their sender score intact.

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