Port 990: FTPS
FTP over implicit TLS.
- Port
- 990
- Protocol
- TCP
- Service
- FTPS
- Exposure
- Expose only with access controls
What is port 990 used for?
Encrypted file transfer with FTP clients.
Is it safe to expose port 990 to the internet?
Encrypted, but FTP still needs extra ports for data and servers have a long bug history. Prefer SFTP, and restrict by source address.
If port 990 seems closed or unreachable
- Check that the FTPS service is running and listening on port 990, not only on 127.0.0.1.
- Check the firewall on the host itself (Windows Defender Firewall, iptables, nftables, ufw) for a rule that allows TCP 990.
- If the host is behind a router, confirm the forwarding rule points to the correct internal address and that your internet provider does not use carrier-grade NAT.
- Test from outside your own network. A port can be open locally and blocked at the edge, or the other way round.
Using port 990 safely
Port 990 can be exposed when the host exists to provide this service, but add controls: restrict source addresses where you can, require strong authentication and encryption, and monitor the logs for repeated failures.
Check whether port 990 is open on your host
The check connects from our server, so it shows what the internet can reach.
Open the port checker