How to change a user's password in Linux? (passwd Command)

Use the passwd command to change passwords securely in Linux: run passwd for your own password (requires current password), or sudo passwd username for others (no current password needed); root can lock/unlock accounts with -l/-u, force reset on next login with -e, and check expiry via chage -l.

To change a user's password in Linux, use the passwd command — it’s simple, secure, and built into every standard Linux system.

Change your own password

Run passwd without any arguments. You’ll be prompted to enter your current password, then type and confirm the new one. The system checks for basic strength (e.g., not too short or based on your username), but doesn’t enforce complexity unless configured via PAM.

• No special privileges needed — just log in as that user
• Passwords are stored encrypted in /etc/shadow, not plain text
• If you forget your password, you’ll need root access or physical/console access to reset it

Change another user’s password (as root)

Only users with root or sudo privileges can change someone else’s password. Use sudo passwd username.

• You won’t be asked for the target user’s current password
• The new password takes effect immediately for all login methods (SSH, console, GUI, etc.)
• Use sudo passwd -l username to lock an account (adds a ! prefix to the password hash)
• Use sudo passwd -u username to unlock it

Force password change on next login

Use sudo passwd -e username to expire the password immediately. Next time that user logs in, they’ll be required to set a new password before proceeding.

• Works only if the system uses PAM and the pam_pwquality or similar module is active
• Helpful for onboarding or after security incidents
• Check expiry status with chage -l username

Set password via script or non-interactively (not recommended for production)

You can pipe input to passwd using echo and chpasswd, but avoid this unless necessary — it risks exposing passwords in process lists or shell history.

• Safer option: echo "username:newpassword" | sudo chpasswd
• Never use echo "newpass" | passwd — it may fail or leak the password
• For automation, prefer SSH key auth or tools like Ansible with encrypted vaults

Basically, passwd does one thing well — change passwords securely and reliably. Just remember who you are, who you’re changing it for, and whether you have the right permissions.

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