Good morning and thank you for posting on the Final Fantasy XIV Technical Support Forums.

The above poster is correct. You can play the game on multiple PS4s as long as you are not trying to log into more than on at the same time. Please be aware that logging into a different device or a different IP address may trigger a login restriction. If this happens, simply reset your password. You can also add a security token to the account to prevent this.

Thank you for visiting the Final Fantasy XIV Technical Support Forums.