Configuring your domain with NS/MX

With this option, we host your DNS and automatically make sure all the correct entries are set for your email.

We provide a control panel for full customisation of your DNS records should you need it. Our nameservers are fast, reliable and secure. Our web interface for managing DNS is simple, but still powerful enough to allow any number of records of any type.

There's just three simple steps to set up your domain:

  1. Add your domain
  2. Domain registration configuration.
  3. Add email addresses at your domain


Optional configuration

1. Add your domain

  1. Go to the Settings → Domains screen. .
  2. Add your domain(s) (e.g. Using the "Add Domain" button brings up the new domain screen. Type your domain into the text box.

2. Domain registration configuration

Note: Updating your DNS is a high visibility change: we recommend updating it during a time when your site has low traffic

  1. Log in to the control panel supplied by your domain registrar.
  2. Then look for where you can change the "name servers" for your domain. You want to make sure there are only two values, and that the two values are:


3. Add email addresses at your domain

To set up email addresses for your custom domain, add aliases at Settings → Users & Aliases. Add as many as you need, you may also choose to add a catchall alias so any mail addressed to your domain comes to you, no matter what address is used.

Creating an alias also creates a matching account identity. This lets you send mail from your account using the email address matching that alias. You can customise other settings too, such as your signature.

If you'd like to configure your account to primarily send using one of your custom domain addresses:

  1. Navigate to the Settings → Identities & Fetch screen.
  2. Select your alias in the "Compose new messages from <address> by default".

You can also select an identity to use as the default account to use for mail being sent from within a given folder.


Depending on the TTL values for your previous DNS settings (if any), it may take up to a day for the changes to propagate across the internet. Normally it's a lot faster: just a matter of minutes. Messages sent to the addresses you added on the aliases screen should now arrive in your Inbox.

Optional domain configuration

System email addresses

The email standard requires that the email address be a valid email address. Because of this, even if you don't set up an alias for that address, we will deliver any email sent to that address to the owner of the domain.

It's also best practice to support By default, if you don't set up your own alias for, we'll automatically direct all email sent to to our automated abuse handling system.

Subdomain addressing and mail routing

On the Settings → Domains screen, you can control subdomain addressing and mail routing.

The Mail: Subdomain section lets you control how Fastmail handles subdomain addressing for your domain. There are three options:

The Mail: Routing section lets you choose how mail to this domain is handled. Use: