Does Fastmail work with authenticator apps like MS Authenticator App?

Yes. Fastmail supports TOTP authenticator apps, so you can generate its two-factor codes in MS Authenticator App.

Is Fastmail two-factor authentication free?

Yes. Enabling authenticator-app 2FA on Fastmail is free — you only need the free MS Authenticator App.

What if I lose access to my Fastmail 2FA codes?

Use the backup or recovery codes you saved during setup. If you didn't save them, contact Fastmail support to regain access, then re-add the account to MS Authenticator App.

Should I use an authenticator app or a security key on Fastmail?

Fastmail supports both. An authenticator app like MS Authenticator App is free and works on any phone; a hardware security key adds phishing resistance. You can enable both.

How to enable 2FA on Fastmail

← Fastmail overview Supported

Protect your Fastmail account with two-factor authentication (2FA). Once enabled, signing in also requires a one-time code from your authenticator app — not just your password.

Step-by-step setup

1
Sign in to Fastmail and open your Fastmail account security settings.
2
Turn on two-factor authentication and choose the authenticator-app option.
Look for "Authenticator app", "Authentication app", or "TOTP" rather than SMS.
3
Scan the QR code with MS Authenticator App.
Open MS Authenticator App, tap add, and point your camera at the QR code Fastmail displays. Can't scan? Enter the setup key manually instead.
4
Enter the 6-digit code to confirm.
Type the code MS Authenticator App generates to verify and link your Fastmail account.
5
Save your backup codes.
Store the recovery codes Fastmail gives you somewhere safe — you'll need them if you lose your phone.

Menu names on Fastmail can change — the official Fastmail 2FA documentation ↗ always has the exact, current path.

Frequently asked questions

Does Fastmail work with authenticator apps like MS Authenticator App?: Yes. Fastmail supports TOTP authenticator apps, so you can generate its two-factor codes in MS Authenticator App.
Is Fastmail two-factor authentication free?: Yes. Enabling authenticator-app 2FA on Fastmail is free — you only need the free MS Authenticator App.
What if I lose access to my Fastmail 2FA codes?: Use the backup or recovery codes you saved during setup. If you didn't save them, contact Fastmail support to regain access, then re-add the account to MS Authenticator App.
Should I use an authenticator app or a security key on Fastmail?: Fastmail supports both. An authenticator app like MS Authenticator App is free and works on any phone; a hardware security key adds phishing resistance. You can enable both.

Generate your Fastmail codes in MS Authenticator App

Free, offline, and encrypted. One tap for every 6-digit code.

Get the app

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