Port 110: POP3
Port 110 is POP3, which downloads mail from a server to a single device and usually removes it from the server. The encrypted variant, POP3S, uses port 995.
TCPEmailUnencrypted by defaultIANA assigned
| Port number | 110 |
|---|---|
| Service | Post Office Protocol v3 |
| Protocol | TCP |
| Category | |
| Default encryption | No |
Security note. Port 110 is not encrypted by default. Restrict it to trusted networks, or use an encrypted alternative where one exists, to avoid exposing credentials and data in transit.
Frequently asked questions
What is port 110 used for?
Port 110 is POP3, which downloads mail from a server to a single device and usually removes it from the server. The encrypted variant, POP3S, uses port 995.
Is port 110 TCP or UDP?
Port 110 (POP3) uses TCP.
Is port 110 secure?
Port 110 is not encrypted by default. Where possible, use an encrypted alternative or tunnel it over TLS or a VPN.
Should I open port 110 on my firewall?
Only if you specifically need POP3. Expose it to the smallest set of trusted sources, and never open database or Windows-service ports to the whole internet.