Sims 4 CAS Backgrounds

The CAS background is the room your Sim stands in while you build them, and the base game gives you one: a flat grey-blue void with a soft spotlight. It is fine for judging a skin tone, and it is the reason so many CAS screenshots look unfinished. A CAS background replacement swaps that room for something else, from a clean single-colour studio to a fully furnished bedroom with a mirror on the wall.

This page is only CAS backgrounds: 102 of them, sorted by downloads. Loading screens and main-menu overrides used to sit in the same pile, and we moved them to the loading screens page, so everything here changes the CAS room and nothing else. The grid splits roughly three ways. Plain backdrops: solid pinks, greens, pastels, black and white, and pattern walls for people who want the Sim and nothing else in frame. Styled rooms: closets, attics, bedrooms, a library, a recording studio, a vinyl store and beaches, several of them with a mirror so you can see the back of an outfit. And themed sets: Y2K, Sanrio, anime, Disney, pride, and a seasonal run of winter and Valentine's Day rooms.

Ellcrze and PILARLEON23 made nearly a fifth of the page between them, with Katverse and Shasims next.

Two practical notes. Most CAS backgrounds replace the same game file, so only one works at a time. If you install two, the one that loads last wins. And a busy room with coloured lighting makes a skin overlay or a makeup swatch harder to judge, so a lot of people keep a plain backdrop for building and a styled room for the screenshot.

Everything in this grid is Sims 4 only and filtered to SFW. Sort by downloads for the rooms people already use, or scroll for the single-file finds.