FastMail Configuration

Yesterday I wrote about my move to FastMail and how smooth that went. I mentioned, that the only caveat was the fact that I had to manually configure the clients to work with FastMail’s IMAP and SMTP servers. This is not as simple as for Google Mail or Yahoo and required me some fine-tuning. So I thought it might be a good idea to share my configuration.

Update: Turns out, there was another issue. I wrote about that one in a (link: /blog/fastmail-configuration-follow-up text: separate post).

For me, the configuration seems to differ a bit depending on the device I use. So let’s split split it up into the following two categories.

FastMail on OS X

I don’t want to explain the basic setup that has been described on FastMail’s support page again. I just want to mention what I had to change to make it work reliably.

I had some issue with additional directories for sent messages that kept re-appearing on the web interface. This was caused by which tried to save sent messages on it’s own. To fix this, uncheck Store sent messages on the server within Mailbox Behaviors on the settings view of your account. Additionally, you need to check Sent Items on SMTP for all your Personalities in AdvancedPersonalities. This should fix that.

Drafts, Junk, and Trashed messages are configured to be stored on the server as well. In comparison to the Sent Messages this is only set on the client side.

FastMail on iOS

There is an official guide for iOS as well.

I had to manually set all the mailboxes for iOS to use in Advanced to the corresponding server mailboxes.


You also might want to turn of the notes sync, especially if find additional directories (see Sent Messages) as annoying as I do. FastMail does not support syncing notes anyway.

Also, do not forget to set the IMAP prefix path. This is in the original setup guide, however, I managed to forget about that on one client and this caused some weird listing behavior.

I don’t use the Address Book or Calendar sync (yet). I’m still on iCloud with those services. I will let you know when I moved those services, too.

Hope this helps.