331
FTP
331 Username OK, Need Password
User name okay, need password. The server recognized the username and is waiting for the corresponding password to complete authentication.
On this page
When You See This Code
After sending the USER command with a valid username. The server is prompting for the PASS command.
How to Fix
Send the PASS command with the correct password. If you get 530 after PASS, the password is wrong — verify your credentials.
Specification
Compare With
Guides
FTP Reply Codes: Understanding File Transfer Responses
DNS & Networking
TCP Three-Way Handshake and Connection Lifecycle
DNS & Networking
Essential Network Debugging Tools: ping, traceroute, mtr, and tcpdump
DNS & Networking
RFC 959: FTP Protocol Deep Dive
Protocol Deep Dives
TLS 1.3: Faster, Simpler, More Secure
Protocol Deep Dives
Migrating from FTP to SFTP: A Complete Transition Guide
Migration & Upgrades
HTTP Access Log Management: Rotation, Parsing, and Analysis
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Frequently Asked Questions
What is FTP 331 Username OK, Need Password?
User name okay, need password. The server recognized the username and is waiting for the corresponding password to complete authentication.
When do you see FTP 331 Username OK, Need Password?
After sending the USER command with a valid username. The server is prompting for the PASS command.
How to fix FTP 331 Username OK, Need Password?
Send the PASS command with the correct password. If you get 530 after PASS, the password is wrong — verify your credentials.