There are a few ways to do this, depending upon your Apple TV model.
If you subscribed via Apple TV 3 or earlier:
- Launch CBS All Access on your Apple TV.
- Navigate to Settings > Link Subscription to CBS Account.
- After choosing "Link Subscription to CBS Account", you will be presented with an activation code, and prompted to visit cbs.com/appletv on your computer or mobile device to enter the activation code.
- After entering your activation code, your Apple TV screen will refresh.
- You will see a confirmation screen that reads "CBS Account Activated".
- Now you can sign in to CBS All Access on any device!
If you subscribed via Apple TV 4 or 4K:
- Simply sign in using your CBS All Access email address and password.