Fastmail SMTP Settings
With the right SMTP settings, getting your outgoing mail up and running with Fastmail is a breeze. Fastmail recommends port 465 with SSL/TLS. Use port 587 with STARTTLS only if your app doesn’t support SSL/TLS on port 465:
| Option | Description |
|---|---|
| SMTP Host: | smtp.fastmail.com |
| SMTP Port: | 465 (SSL) or 587 (STARTTLS) |
| SMTP Username: | Your full email address (name@domain.com) |
| SMTP Password: | Your app-specific password. You cannot use your regular Fastmail password. |
Fastmail Server Settings For Receiving Email
Use the following POP and IMAP settings to connect to your mail account using a desktop email client:
Fastmail POP settings
Some people prefer POP over IMAP, even though IMAP has largely replaced it. POP downloads only your Inbox by default. To download another folder, add its name to your username, such as yourname+foldername@fastmail.com.
| Option | Description |
|---|---|
| POP3 Host: | pop.fastmail.com |
| POP3 Port: | 995 |
| Requires SSL: | Yes |
| POP3 Username: | Your full email address (name@domain.com) |
| POP3 Password: | Your app-specific password. You cannot use your regular Fastmail password. |
Fastmail IMAP settings
IMAP is the best option if you want to read your emails in your mail client from your Fastmail server. Fastmail recommends IMAP because it syncs both ways, so changes in your mail app also show up in the Fastmail web interface.
| Option | Description |
|---|---|
| IMAP Host: | imap.fastmail.com |
| IMAP Port: | 993 |
| Requires SSL: | Yes |
| IMAP Username: | Your full email address (name@domain.com) |
| IMAP Password: | Your app-specific password. You cannot use your regular Fastmail password. |
Clean Email Makes Fastmail Even Better
Setting up Fastmail with IMAP or POP is just the beginning. Once your email is up and running, Clean Email helps you keep it neat and stress-free. With Auto Clean, you can set rules to automatically archive or delete emails from specific senders, like old shipping updates or expired promotions. It’s the easiest way to avoid clutter without lifting a finger.
Using Smart Folders, you’ll see your emails grouped into categories like Newsletters, Online Shopping, and Finance, no setup needed. This helps you instantly spot what’s important and bypass Gmail 50 email limit. It’s much quicker than scrolling through emails one by one.
Have a bunch of messages with big attachments eating up space? Use Clean Email’s Filtering to quickly find and delete large emails. Just set your filter for size, and you’ll have a cleaner inbox—and more storage—within minutes.
And the best part? Clean Email syncs directly with Fastmail, so whatever you clean up in Clean Email is instantly reflected in your other devices. You don’t have to change how you check your mail—just enjoy a cleaner inbox wherever you are.
Notes and Additional Information
Your regular Fastmail password won’t work in email, calendar, or contacts apps. Each app needs its own app password. To create one:
- In Fastmail on the web, go to Settings → Privacy & Security.
- Under Connected apps & API tokens, click Manage app passwords and access, then click New app password. Enter your password if asked.
- Choose a name from the list, or select Custom to enter your own, such as "Outlook on PC".
- Choose what the app can access. The default, Mail, Contacts & Calendars, covers IMAP, POP, SMTP, CardDAV, and CalDAV.
- Select Files (WebDAV) instead if the app needs access to Fastmail's file storage.
- Click Generate password, paste it into your app, and click Done once the account works.
💡 Note: If your network blocks the standard ports, use Fastmail’s proxy servers instead: imaps-proxy.fastmail.com, pops-proxy.fastmail.com, and smtps-proxy.fastmail.com. They work on any port and use SSL/TLS.
Looking for Zoho settings or Yahoo Mail settings? Our Blog's Email Settings category contains specs for all major mail service providers.
POP3 vs. IMAP: What’s The Difference
POP and IMAP can be compared using a simplified version of how they operate.
Email clients connect to email servers first when using POP. All of the mail on the server is retrieved once it's successfully connected to the server. Messages are then stored locally on your device to access them through your mail client. Many POP setups then remove the messages from the server, so they’re only accessible on the device that saved them. POP also doesn’t sync changes, such as moving a message, back to the server.
Even though most POP setups delete your email from the server by default, you can choose to keep copies of your messages. While this can be useful if you're concerned about losing your mail, it can also quickly cause you to run out of server space.
IMAP is a little different from POP in its operation. Connect to an email server and retrieve your desired content (such as all new emails or a specific message's contents). Because it's locally cached, you can continue working on your device as soon as you change your email. The server processes and saves your changes before disconnecting you.
The key difference with IMAP is that you're not downloading all of your emails to your computer. Instead, you're using your email client to access and manage the ones already on the server. Only cached versions of information are retained on your device until you deliberately download something.
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