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.

Note: Basic plans do not include access to IMAP, SMTP, CalDAV, or CardDAV.

Troubleshooting:

Email

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

IMAP

Server imap.fastmail.com
Port 993
SSL/TLS Encryption Enabled, but not STARTTLS
Username Your Fastmail email address, including the domain.
Password Your 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

Server pop.fastmail.com
Port 995
SSL/TLS Encryption Enabled, but not STARTTLS
Username Your Fastmail email address, including the domain.
Password Your app-specific password. You cannot use your regular Fastmail password.

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, e.g. yourusername+foldername@fastmail.com

Please note: Folder names are case-sensitive, so the username must be capitalized to match the folder. Additionally, this method of accessing folders will not work if the folder name contains special characters. For more information, please see our Accessing folders via POP help page.

SMTP

Server smtp.fastmail.com
Port 465
SSL/TLS Encryption Enabled, but not STARTTLS
Authentication PLAIN
Username Your Fastmail email address, including the domain.
Password Your 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

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.

Server https://caldav.fastmail.com/
SSL/TLS Encryption Yes (required)
Username Your Fastmail email address, including the domain.
Password Your app-specific password. You cannot use your regular Fastmail password.

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

You can get this URL from your Settings → Calendars screen. Find the calendar that you want to add to the client, and click on the Export link. There will be a popup that displays the CalDAV URL. This is the URL you'll need to enter in to your client for CalDAV setup.

Contacts

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

We ended support for LDAP access in December 2021, as we had very few customers using it and continuing to support LDAP was no longer sustainable. If you have previously used LDAP to access your contacts, you may be able to continue accessing your contacts using CardDAV.

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.

Server https://carddav.fastmail.com/
SSL/TLS Encryption Yes (required)
Username Your Fastmail email address, including the domain.
Password Your 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.

  • Personal contacts:
    • Server address: https://carddav.fastmail.com/dav/addressbooks/user/<username@domain.tld>/Default
      • Replace <username@domain.tld> with your full Fastmail username, including the domain.
      • Example: for trythis@example.com the address is https://carddav.fastmail.com/dav/addressbooks/user/trythis@example.com/Default
    • Username: <username>+Default@<domain.tld>
      • Note the additional +Default between your username and domain.
      • Example: for trythis@example.com the username is trythis+Default@example.com
  • Shared contacts:
    • Server address: https://carddav.fastmail.com/dav/addressbooks/user/<username@domain.tld>/<masteruser@domain.tld>.Shared
    • Username: <username>+Shared@<domain.tld>
      • Note the additional +Shared between your username and domain.
      • Example: for trythis@example.com the username for shared contacts is trythis+Shared@example.com
      • Still use your Fastmail username and an app password to authenticate.

Files

You can access and manage your account's files using WebDAV. Most modern browsers will allow you to view files this way 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

Server https://webdav.fastmail.com/
Username Your Fastmail email address, including the domain.
Password Your app-specific password, with access set to Files (WebDAV). 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.

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; other addresses will not work.

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

  • username@your.domain
  • username#your.domain
  • username/your.domain
  • username=your.domain

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:

IMAP imaps-proxy.fastmail.com
POP pops-proxy.fastmail.com
SMTP smtps-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.

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