How to Change Time Format in Ubuntu Linux

This post describes steps you can take to change the time format (12 / 24 hour) in Ubuntu Linux.

Ubuntu Linux will display the date and time on the Lock Screen, System menu on your desktop as well as other applications that depend on your system’s time.

The time format displayed on the lock screen is the same configured within Ubuntu system control panel. Whatever format selected there will be displayed system wide.

The lock screen is the screen or curtain you see when you turn on your computer before the sign in screen. It is also displayed once your computer is locked after you stepped away.

To login or return to your desktop when your session is locked, press any key on the keyboard or click the mouse to raise the lock screen curtain to reveal the logon screen.

Enter your password to logon.

How to show 12 or 24-hour time format in Ubuntu Linux

As mentioned above, Ubuntu Linux has time settings that allow users to choose a 12 or 24 hour-based format.

The 12-hour time format is known as standard format. The 24-hour based format is sometime called military time format.

Below is how to change the time format in Ubuntu Linux.

Ubuntu Linux has a centralized location for majority of its settings. From system configurations to creating new users and updating, all can be done from the System Settings panel.

To get to System Settings, open the Activities overview and start typing Settings.

Alternatively, click on the System menu at the top-right corner of the top bar on your desktop.

On the System menu, select Settings as highlighted below.

In the Settings app, click on Date & Time tile.

In the System Settings -> Date & Time settings pane, select the Time Format tile, then choose the format you want.

  • 24-hour – 24 hour-based format or also known as military time.
  • AM/PM – 12 hour-based format or also known as standard time.

Changes should take place immediately.

That should do it! You can now close the settings app.


This post showed you how to change the time format in Ubuntu Linux. If you find any error above or have something to add, please use the comment form below.