A catch-all functionality that is activated for a certain email mailbox will allow you to receive email messages that are sent to addresses that do not actually exist. In other words, if you remove an email address and someone still sends an email to it, or to any miswritten email address under the same domain, you will receive the email in the catch-all mailbox. Using this functionality implies that you won’t miss an email for any reason, which could be essential in case you run some company, for example. Since you may start receiving unsolicited messages, you can combine the catch-all option with anti-spam filters so as to receive only real emails in your inbox. Just one single mailbox per domain can be a catch-all one and email forwarding cannot be activated for a catch-all mailbox.