The latest Ubuntu systems use GNOME as a default theme. GDM3 is the default display manager which is responsible for loading the login screen. We need to tweak settings in gdm3 to change the background of the login screen.

This tutorial will help you to change the default login screen background on Ubuntu systems.

Install Required Tools

First of all, install a required library on your system.

sudo apt install libglib2.0-dev-bin

Now download the script that will help you with setting up the login screen background wallpaper on Ubuntu systems.

wget -qO - https://github.com/PRATAP-KUMAR/ubuntu-gdm-set-background/archive/main.tar.gz | tar zx --strip-components=1 ubuntu-gdm-set-background-main/ubuntu-gdm-set-background 

To find out the command help run the following command:

./ubuntu-gdm-set-background --help 

Change the Login Screen Background

You can set an image, solid color, and horizontal or vertical gradient color at the Ubuntu login screen running with Genome display manager (GDM).

Use one of the following commands to change the login screen background of your choice:

  • Set an image – Use the following command to set an image to the login background.
    sudo ./ubuntu-gdm-set-background --image /home/user/backgrounds/image.jpg 
    
  • Set a solid color – You can also set an solid color to Ubuntu login screen. Use the following command with hex color code. You can generate hex code here.
    sudo ./ubuntu-gdm-set-background --color #aAbBcC 
    
  • Set a horizontal gradient color – It also allows you to make gradient color with two colors. To set the horizontal gradent use following command:
    sudo ./ubuntu-gdm-set-background --gradient horizontal #aAbBcC #dDeEfF 
    
  • Set a vertical gradient color – Vertical gradient of two colors can be set with command:
    sudo ./ubuntu-gdm-set-background --gradient vertical #aAbBcC #dDeEfF 
    
  • Reset all changes – You can reset all changes to the original by running command:
    sudo ./ubuntu-gdm-set-background --reset 
    

Here are a few screenshots of the login screen after setting up with the above commands.

Changing the Login Screen Background in Ubuntu 22.04 & 20.04 GDM3 ubuntu Wallpaper
Set an Image at login screen
Changing the Login Screen Background in Ubuntu 22.04 & 20.04 GDM3 ubuntu Wallpaper
Set the solid color at Ubuntu login screen
Changing the Login Screen Background in Ubuntu 22.04 & 20.04 GDM3 ubuntu Wallpaper
Setting up gradiant colors at login screen

Conclusion

This tutorial helped you with changing the login screen background with custom colors on Ubuntu systems. You can revert all changes anytime to get the default login screen.