Fastmail SMTP and IMAP settings
SMTP and IMAP settings for Fastmail, which uses app passwords for all third-party connections.
Outgoing mail (SMTP)
| SMTP server | smtp.fastmail.com |
|---|---|
| Port | 465 (SSL/TLS) or 587 (STARTTLS) |
| Username | Your full Fastmail address |
| Password | See authentication note below |
Incoming mail (IMAP)
| IMAP server | imap.fastmail.com |
|---|---|
| Port | 993 |
| Security | SSL/TLS |
Authentication
Fastmail requires an app password (Settings, Privacy & Security, App Passwords) for any external SMTP or IMAP client.
How to set up Fastmail in your email tool
- Open your email client or sending tool and add a new account.
- For incoming mail, choose IMAP and enter server imap.fastmail.com, port 993 (SSL/TLS).
- For outgoing mail, enter the SMTP server smtp.fastmail.com on port 465 (SSL/TLS) or 587 (STARTTLS).
- Set the username to your full fastmail address, and use the password described in the authentication note above.
- Save the account and send a test email to confirm it works.
Connecting is the easy part. Landing in the inbox is not.
Once Fastmail is connected you can send, but whether your cold email reaches the inbox depends on SPF, DKIM, and DMARC authentication, your sender reputation, and proper domain warmup. Scheduler Zero handles warmup and deliverability so your emails actually land.