Use These Fastmail IMAP Settings to Access Email

Copy and Paste Fastmail IMAP Settings

Want to access all your Fastmail emails and folders and synchronize actions automatically between email programs and Fastmail on the web? Find here the Fastmail IMAP settings to copy, paste and use (including alternatives if your secure IMAP port is blocked).

First, Precision Labor Hut

In 1892, Kintarō Hattori purchased a saltpeter factory that was no longer in use. He turned it into his Seikōsha, that very (and literally in Japanese) precision labor hut producing—wall clocks. Today, we still know and value Seiko for its watches, of course.

Looking for precision for your email and want to synchronize folders like Seikōsha clockwork? Let IMAP deliver Fastmail to your every hut and home:

Use These Fastmail IMAP Settings to Access Your Email

NameValue
IMAP server
TLS securityyes (if available)
SSL securityyes (if TLS is not available)
IMAP port (SSL/TLS)
STARTTLS securityno
UsernameYour full Fastmail email address (including the domain)
PasswordA Fastmail application password (you cannot synchronize mail using your regular Fastmail password)

For sending, you can use the Fastmail SMTP settings (also copy and paste). As an alternative, Fastmail also offers POP access, which only downloads new emails but does not synchronize folders.

Use These Fastmail IMAP Settings to Access Your Email: FAQ

Using ‘@’ in the username does not work; are there alternatives?

Yes.

If your email program does not allow you to insert the @ sign in the IMAP username, you can

  • replace it with # = or / .
    Example: If the username with @ is me@fastmail.fm, try using me/fastmail.fm instead.

Port 993 is blocked. Can I use Port 143 instead for Fastmail IMAP access?

Yes.

If accessing Fastmail through standard port 993 fails, try the following alternative settings:

NameValue
Alternative IMAP server
IMAP port
other IMAP port alternatives21, 80, or any other open port
Require TLSyes (if available)
Require SSLyes (if TLS is not available)
STARTTLS securityno
UsernameYour full Fastmail email address
PasswordA Fastmail application password

What should I use as the INBOX prefix?

For accessing Fastmail in an email program or service, it is best to

  • leave the inbox or root folder prefix empty in your IMAP settings.

How does Fastmail separate folders?

Fastmail uses the standard / (slash) to create a folder hierarchy in IMAP.

(Fastmail IMAP settings first published August 2020, updated January 2024)

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