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How to filter sent mail?

5582728 shared this question 20 months ago
Need Answer

I'd like to filter the mail I send into different folders depending on the alias it is sent from.

Filtering works fine with incoming mail - mail to 1@domain>folder1, mail to 2@domain to folder2 etc. At present it doesn't seem to work for outgoing mail though. Is this possible?

Comments (3)


I'm wondering the same.


I came up with something that works, if you can live with always having an extra address automatically placed into the BCC field.

Go to Hamburger Menu > Settings >Mail, scroll down to "Always add the following recipient to blind carbon copy (BCC)" and add a dedicated fcc (File Carbon Copy) email address like user+fcc@mailbox.org (where 'user' is your mailbox.org username).

Now create a new filter rule that applies if both the following are true:

  • From Contains desiredalias@customdomain.tld
  • Header Name "Delivered-To" is exactly user+fcc@mailbox.org

with an action that files the mail into the desired "sent" folder for the alias. Disable "process subsequent rules" for the rule and make sure its above any other rules that would catch these messages first, such as a rule that would apply to all mail for the mailbox.org domain.

Now test outgoing mail, incoming mail, and you should probably test all other rules with a matching test message to make sure you didn't break anything.


After further experiments I went with:

  • Header Delivered-To Is Exactly user+fcc@mailbox.org
  • Header Return-Path Is Exactly <alias@customdomain.tld>

For the filter rule, and I moved these FCC rules to the top of the list.

You can poke around in View Source for an email to see what you might want the filter to be.