| Protocol | Security Setting | Port Number(s) |
|---|---|---|
| SMTP (sending mail) | Encrypted - TLS/STARTTLS | 465 |
| SMTP (sending mail) | Encrypted - SSL | 465 |
| SMTP (sending mail) | Unencrypted | 25* (or 26) |
| POP3 (receiving mail) | Encrypted - TLS | 995 |
| POP3 (receiving mail) | Encrypted - SSL | 995 |
| POP3 (receiving mail) | Unencrypted | 110 |
| IMAP (receiving mail) | Encrypted - TLS | 993 |
| IMAP (receiving mail) | Encrypted - SSL | 993 |
| IMAP (receiving mail) | Unencrypted | 143 |
Many ISPs block unauthenticated email sending on port 25. It is recommended you always enable SMTP Authentication and avoid using port 25 (e.g. by enabling TLS/SSL).
The recommended settings are marked in bold.
To decide between using POP3 or IMAP for receiving mail, see our guide What is the difference between IMAP and POP3 for email?
