How to Completely Disable the ‘Screen Blank’ (Sleep) Timer in Ubuntu

By default, if you step away from your Ubuntu desktop for five minutes without touching the mouse or keyboard, the operating system will automatically blank the screen and lock your session to save power and protect your privacy. While this is excellent security practice in a busy corporate office, it can be incredibly frustrating if you are using Ubuntu at home to read a long document, watch a video that doesn’t properly prevent sleep, or monitor a terminal process running in the background.

If you are constantly having to jiggle the mouse just to keep your screen awake, you can completely disable the Screen Blank timer, forcing your display to remain on indefinitely until you manually choose to turn the computer off or put it to sleep.

Disabling Screen Blank in System Settings

You can adjust or completely disable this power-saving feature directly from the main GNOME Settings menu.

1. Click anywhere in the top-right corner of your screen (where the network and battery icons are located) to open the quick settings menu.
2. Click the Gear icon (Settings) from the dropdown.
3. In the left-hand navigation sidebar of the Settings window, scroll down and click on Power.
4. In the main Power panel, look for the section labelled Power Saving Options.
5. Find the setting titled Screen Blank. Next to it, you will see a dropdown menu (likely set to “5 minutes”).
6. Click the dropdown menu and select Never from the list.

Your screen will no longer automatically turn off to save power, no matter how long you leave the computer idle.

Disabling the Automatic Screen Lock

Even if you disable the Screen Blank feature, Ubuntu may still have an automatic security lock enabled, which forces you to type your password if the system detects inactivity. If you are configuring a home computer and want a completely uninterrupted experience, you should disable this as well.

1. While still in the Settings app, scroll down the left-hand sidebar and click on Privacy (or “Privacy & Security” depending on your version of Ubuntu).
2. In the Privacy panel, click on Screen Lock.
3. Look for the toggle switch labelled Automatic Screen Lock.
4. Click the switch to turn it Off.
5. Close the Settings window.

With both of these settings disabled, your Ubuntu computer will remain completely awake, fully bright, and unlocked indefinitely.