Connect Fastmail to Pop3Fetch

Step 1 — Sign in to Fastmail

Open app.fastmail.com and sign in with your normal credentials. App passwords are managed entirely through the web app — no separate account portal.

Step 2 — Generate an app password

1. Click the Settings gear (top-right of the web app)
2. Go to Privacy & Security → Integrations (sometimes labeled Connected apps & services on older accounts)
3. Click New app password (or the + button)
4. Name it — Pop3Fetch works well
5. For the access level, choose Mail (IMAP/POP/SMTP) — Pop3Fetch only needs read access to your inbox
6. Click Generate. Fastmail will display a long alphanumeric password. Copy it now — Fastmail won't show it again.

Step 3 — Add Fastmail to Pop3Fetch

1. Sign in to app.pop3fetch.com
2. Click Add an account
3. Fill in:
   • IMAP host: imap.fastmail.com
   • IMAP port: 993
   • Username: your full Fastmail email (e.g. yourname@fastmail.com) or your custom-domain address
   • Password: paste the app password from Step 2
4. Click Save

Pop3Fetch verifies the connection and starts importing on the next sync cycle — within 5 minutes on Basic, 1 minute on Pro.

Common issues

"Authentication failed"

Two likely causes: you used your Fastmail login password instead of the app password, or the app password's access level doesn't include Mail (IMAP). Re-check Settings → Privacy & Security → Integrations and make sure the Pop3Fetch app password has Mail access.

Custom domains

Fastmail handles custom domains transparently — there's no separate IMAP server. Use your full custom-domain address (e.g. you@yourdomain.com) as the username, with the standard imap.fastmail.com server. The app password works for any address on your account.

Aliases

Fastmail aliases all deliver into the same primary inbox, so there's nothing extra to configure. Connecting your primary Fastmail address syncs all alias mail as well.

I lost the app password

Fastmail only displays each app password once. If you lost it, generate a new one — you can have any number active. Revoke the old one from the same Integrations page if it's not in use anywhere else.

Notes

• App passwords don't expire on their own. They stay valid until you revoke them or change your Fastmail account password.
• Fastmail's app passwords are scoped — you can issue narrow ones that only allow Mail access. Pop3Fetch only needs Mail; don't grant other scopes.
• Each app password should be used by exactly one service. If you also connect Fastmail to another mail client, generate a separate app password for it.
• Revoking the Pop3Fetch app password at Fastmail will immediately stop Pop3Fetch from importing — useful as a fast "off switch" if you ever need one.