Port 119: NNTP

Port 119 is NNTP, the Network News Transfer Protocol used to post and read Usenet newsgroup articles. The encrypted version, NNTPS, uses port 563.

TCPLegacy protocolsUnencrypted by defaultIANA assigned
Port number119
ServiceNetwork News Transfer Protocol
ProtocolTCP
CategoryLegacy protocols
Default encryptionNo
Security note. Port 119 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.

How do I check whether port 119 is open?

Port 119 carries TCP, so a connection either completes its handshake or it does not, which makes the check definitive.

QuestionCommandWhat to know
Is it open on a remote host?nc -vz example.com 119A TCP handshake either completes or it does not, so netcat gives a definitive answer in one line.
Same check on WindowsTest-NetConnection example.com -Port 119Built into PowerShell. TcpTestSucceeded in the output is the answer; telnet is not installed by default on modern Windows.
What is listening locally?ss -tlnp | grep ':119 'Lists the process bound to port 119 on Linux. On macOS use lsof -nP -iTCP:119 -sTCP:LISTEN, on Windows netstat -ano | findstr :119

Replace example.com with the host you are testing. A blocked port and a port with nothing listening on it look identical from the outside, so if a service should be running, check locally before blaming the firewall.

Frequently asked questions

What is port 119 used for?

Port 119 is NNTP, the Network News Transfer Protocol used to post and read Usenet newsgroup articles. The encrypted version, NNTPS, uses port 563.

Is port 119 TCP or UDP?

Port 119 (NNTP) uses TCP.

Is port 119 secure?

Port 119 is not encrypted by default. Where possible, use an encrypted alternative or tunnel it over TLS or a VPN.

Should I open port 119 on my firewall?

Only if you specifically need NNTP. Expose it to the smallest set of trusted sources, and never open database or Windows-service ports to the whole internet.