There are two ways that you can play Call of Duty for free, and they're both dramatically popular. Firstly, there's the Warzone ecosystem, which is made up of Call of Duty Warzone and Call of Duty Warzone 2.0.

Featured in Call of Duty: World at War, Call of Duty: Black Ops, Call of Duty: Modern Warfare 3, Call of Duty: Black Ops II, Call of Duty: Black Ops Cold War and Call of Duty: Vanguard is a hardcore version of Free-for-All.

PlayStation 4 Cross-Gen Edition: Includes a cross-gen version of Call of Duty: Modern Warfare II playable on PlayStation 4 and unlocks a free digital upgrade to play on PlayStation 5. Please note: The game disc will be required to play the PlayStation 5 version.

If you bought the physical/disc version of the PS4 game and wanted to have PS5 upgrade version for free*, make sure that your PS5 console already have its disc drive because this feature still requires you to have its existing PS4 game disc to run PS5 version.