The Sims 4 CAS Demo is available for a few players - Sims Online

Curious if you are one of those lucky people? It will magically appear in your Origin! If it doesn't, then you will have to wait until the demo release.

Sims 4 CAS Demo SKehrer's Sim Stuff

The Sims 4 – CAS Demo – Crinrict's Sims 4 Help Blog

Simply Ruthless: The Sims 4 Create-A-Sim Demo

Simply Ruthless: The Sims 4 Create-A-Sim Demo

Simply Ruthless: The Sims 4 Create-A-Sim Demo

Sims 4 CAS Demo SKehrer's Sim Stuff

The Sims 4: Gallery CAS Demo Overview – simcitizens

The Sims 4: Transferring Sims from Demo to Full Game

Create a Sim, The Sims Wiki