How to change the background on a layout in PowerPoint? I want my slides to have the same background.

Yes, you can easily change the background with the following options: in 6 steps:

1. Click the View tab. You see the View tab menu showing up.

2. Click the Slide Master icon in the Master Views group. PowerPoint changes the presentation editing view to slide master editing view.

3. Select the layout you want to change.

4. Check the "Background Style" menu in the "Background" group, then select "Format BackGround" in pulldown menu. You see the "Format Background" panel showing up with these options:

Fill
   o Solid fill
   o Gradient fill
   o Picture or texture fill
   o Pattern fill

Insert picture from file

5. Select "Solid fill" and change color to some light color as the background.

6. Inert a light-colored picture from a file and stretch it to fill the background.

7. Go back to the normal view.

Now all slides based this layout will have the new background.

Note that you need change the background on other layouts too to ensure slides based on other layouts to have the same background.

See the picture below:

⇒ Turn Of and Off Footers on Slides in PowerPoint

⇐ Add Slide Number on a Layout in PowerPoint

⇑ PowerPoint Slid Master, Layout and Template

⇑⇑ MS PowerPoint - Frequently Asked Questions