Port 20 — FTP data
Port 20 (TCP) is used by FTP data. Carries the actual file contents in classic (active-mode) FTP; the control channel is port 21.
Port 20 at a glance
| Property | Value |
|---|---|
| Port number | 20 |
| Transport | TCP |
| Service | FTP data |
| Category | Well-known port |
What it is used for
Carries the actual file contents in classic (active-mode) FTP; the control channel is port 21.
Security considerations
Unencrypted — data and credentials travel in clear text. Prefer SFTP or FTPS.
See our full TCP/UDP port reference and learn how firewalls filter ports in the CyberOps course.
Frequently asked questions
What is port 20 used for?
Port 20 (TCP) is used by FTP data. Carries the actual file contents in classic (active-mode) FTP; the control channel is port 21.
Is port 20 TCP or UDP?
Port 20 uses TCP.
Is it safe to open port 20?
Unencrypted — data and credentials travel in clear text. Prefer SFTP or FTPS.
Related
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