How to change your email address on a Mailman mailing list

I often see people asking how to change their email address for mailing lists.
Most mailing lists - Mailman notably - tends to treat each email address as a given subscription. So it's actually entirely possible to treat the procedure as a two-parter, being 'subscribing with a new address' followed by 'unsubscribing your old address'. More modern installations also support 'changing' your email address... so see Alternative: below.

Two-part process.
This is useful if you want to ensure delivery to the new address before cancelling the old one (a 'soft' transition).

Phase 1: Subscribe your new address

Step 1: Visit the mailing list information page - usually in the footer of every email to the list, is a link.

-----
This is my Mailing list
mailinglist@email.example.com
http://mailinglist.example.com/mailman/listinfo/mailinglist

If you click on the hyperlink you'll see a page about the list. On the page will be links to visit the Archive (may require you to authenticate with a password), instructions on how to post to the list (what email address to send to), and a form through which you can subscribe by entering your name and email address.

Step 2: Fill in the "Subscribing to MailingList" form with your name and email address. If you don't also submit a password, a random one will be generated and emailed back to you with your confirmation of subscription.

Step 3: Check your email for a message asking you to confirm that the address is infact yours. It'll have a link and/or a text string that you should use to confirm your subscription. (This is to prevent people subscribing you without your consent). Once you've done this, your new email address will start receiving traffic.... note that for some mailing lists, a Moderator or Administrator may need to further approve your subscription.

Phase 2: Remove the old address (aka 'how to unsubscribe')

Step 1: Visit the mailing list information page (as above).

Step 2: At the bottom of the page look for the button that says 'Unsubscribe or edit options'. If you leave all other fields blank and click that button, it sends you to another page that'll ask you for the relevant details anyway.

Step 3: Enter your email address - and your password (if known.) If you don't know your password, use the 'Password Reminder' button and the password will be emailed to you.

Step 4: Tick the box 'Yes, I really want to unsubscribe' about half way down the page, and click the adjacent button 'Unsubscribe'. Job done.

Alternative: Change your address
If you just want the quick way to change your address, and are sure you won't have problems as a result

Step 1: Complete Steps 1, 2 and 3 of Phase 2 above, to login to your Mailing list control panel.

Step 2: Under 'Changing your mailinglist membership information' enter your new email address (in both boxes as requested) optionally your name as well, and click on the 'Change my Address and Name' button. This'll send you an email to confirm your action.

Step 3: Click on the link / use the confirmation string given, to confirm the change. Job done.

None of this is very hard, so hopefully this guide will help those using mailing lists I help administer to sort themselves, themselves! For the most part, List administrators should not have to intervene (and it's usually better that they don't). These tools are fully self-service, as you would expect.