Your address does not change
Connect the mailbox you already have. Nothing moves, and there is no new address to learn.
Alternatives
Fastmail is an independent email service. If you also have a Gmail, Yahoo, or work address, Patriot Mail can put your Fastmail next to them in one calm, easy-to-read inbox. You keep your address, and your mail stays with Fastmail.
Patriot Mail does not replace your Fastmail account. It opens the same mailbox, so your mail stays with Fastmail and you can keep using Fastmail's own apps whenever you like.
Fastmail does not accept your login password in other email apps. Create an app password in Fastmail settings, under Privacy and Security, and paste it into Patriot Mail once.
Block a sender, or a whole company by blocking its domain, and their mail is usually deleted as soon as it lands, or the next time you open the app. Unsubscribe in one tap, and use the Subscriptions view to see who writes most.
Patriot Mail is free, with no subscription. Your messages are not permanently stored on Patriot Mail servers, and your inbox data is not sold or used for advertising.
Fastmail asks every email app for an app password. You create one in Fastmail settings, under Privacy and Security, and use it in Patriot Mail.
No. Patriot Mail opens your existing Fastmail mailbox, and your address stays the same.
Yes. Patriot Mail is free to use, with no subscription and no trial that ends.
Ready when you are
Connect the mailbox you already use and get a calmer inbox in about a minute. Free, with no subscription, and the address you have had for years stays exactly where it is.