Server names and ports

These are the standard server name and port details for setting up access to email, contacts and files for your Fastmail account.

You will need to get an app password to connect to these servers. You cannot use your regular Fastmail password.

If you are looking for step-by-step set up instructions to set up your email software, please review our page on how to set up an email client, or see our instructions on setting up files access.

Troubleshooting:

Email

We recommend using IMAP over POP to access your email. Fastmail supports both protocols using the configurations below. You must use SSLTLS with all of the protocols; we do not support insecure access.

IMAP

Serverimap.fastmail.com
Port993
SSL/TLS EncryptionEnabled, but not STARTTLS
UsernameYour Fastmail email address, including the domain.
PasswordYour app-specific password. You cannot use your regular Fastmail password.
Root folder/IMAP path prefix(leave blank)
Folder separator/ (forward slash)

Note: Do not enable secure password authentication (SPA). It is not needed when you use SSL/TLS encryption and it will not work.

POP

Serverpop.fastmail.com
Port995
SSL/TLS EncryptionEnabled, but not STARTTLS
UsernameYour Fastmail email address, including the domain.
PasswordYour app-specific password. You cannot use your regular Fastmail password.

POP from folder. By default, POP will pull emails from your inbox. You can pull emails from a different folder by adding the folder name to your username. For example, yourusername+foldername@fastmail.com. This won't work for folder names with spaces or special characters.

SMTP

Serversmtp.fastmail.com
Port465
SSL/TLS EncryptionEnabled, but not STARTTLS
AuthenticationPLAIN
UsernameYour Fastmail email address, including the domain.
PasswordYour app-specific password. You cannot use your regular Fastmail password.

If your client supports STARTTLS only, you can use port 587 with STARTTLS enabled.

Calendar

Fastmail supports two-way sync of your calendar via the standard CalDAV protocol. This is supported natively by iOS and many desktop calendar applications, and via a plugin on Android devices.

CalDAV access is not available on legacy Personal/Family Lite/Full plans or legacy Business Basic plans.

CalDAV

For clients that support auto-discovery of calendars over CalDAV, use the following details. However, there are some clients that do not support auto-discovery, and they require more work to set up. We have written step-by-step instructions for popular clients.

Serverhttps://caldav.fastmail.com/
SSL/TLS EncryptionYes (required)
UsernameYour Fastmail email address, including the domain.
PasswordYour app-specific password. You cannot use your regular Fastmail password.

Contacts

Fastmail supports two-way sync of your contacts via the standard CardDAV protocol. This is supported natively by iOS and many desktop address book applications, and via a plugin on Android devices.

We also support read-only access to your contacts via the LDAP protocol, which works with some popular mail clients.

CardDAV access is not available on legacy Personal/Family Lite plans or legacy Business Basic plans.

CardDAV

The following details are sufficient for clients that support auto-discovery of contact lists over CardDAV. However, there are some clients that do not yet support this, and they require a little more work to set up. We have written step-by-step instructions for popular clients.

Serverhttps://carddav.fastmail.com/
SSL/TLS EncryptionYes (required)
UsernameYour Fastmail email address, including the domain.
PasswordYour app-specific password. You cannot use your regular Fastmail password.

If your client does not support CardDAV auto-discovery, you may need to use a full URL path to your contact list.

LDAP

You can view your contacts (read-only) in other software, like Outlook or Apple Mail, using LDAP.

Serverldap.fastmail.com
Port636
SSL/TLS EncryptionEnabled (but not STARTTLS)
Username/Bind DNcn=your-username@your-domain,dc=User
LoginPLAIN
PasswordYour app-specific password. You cannot use your regular Fastmail password.
Search base/Base DNdc=AddressBook

The values are case sensitive. It must be exactly ,dc=User on the end of the username part, and the search base must be exactly dc=AddressBook.

LDAP notes

Files

You can access and manage your account's files using either WebDAV or FTP. Most modern browsers will allow you to view files through either but you may want to install a standalone client to help manage or modify your files. You can read more about this in our instructions of how to set up remote file access.

WebDAV

Serverhttps://webdav.fastmail.com/
UsernameYour Fastmail email address, including the domain.
PasswordYour app-specific password. You cannot use your regular Fastmail password.

Your {My Files} directory will be located in /username.your.domain/files/. Alternatively, use the hostname https://myfiles.fastmail.com/ to be rooted in your {My Files} directory.

FTP

Serverftp.fastmail.com
Port21
UsernameYour Fastmail email address, including the domain.
PasswordYour app-specific password. You cannot use your regular Fastmail password.

Your {My Files} directory will be in /username.your.domain/files/. Fastmail also support FTPS, but not SFTP.

Alternative usernames

You need to log in to all services with your full Fastmail username, including the domain, for example username@your.domain. You must use the username you used to sign up your account; aliases will not work.

Because some software has difficulty with the @ symbol in usernames, you can try any of these alternatives:

Firewall access

If you are behind a firewall, some service ports may be blocked. Fastmail has a special proxy system whereby you can access IMAP, POP and SMTP through any port number. All these servers use SSL/TLS. The server names are:

IMAPimaps-proxy.fastmail.com
POPpops-proxy.fastmail.com
SMTPsmtps-proxy.fastmail.com

If you use these server names, you can use any port to access these services. Commonly open ports include 80, 21, 25 and 443.