Call of Duty: Modern Warfare 4 opens its beta to everyone on August 28, moving beyond the preorder-gated early-access period that ran the previous weekend. Activision's official beta guide says the public window begins at 10am PT on August 28 and runs until 10am PT on September 1, with no preorder or beta code required to get in.
The second weekend also broadens the supported-platform list. Xbox Series X|S, Xbox PC, PlayStation 5, Steam and Battle.net remain in the mix, while Nintendo Switch 2 joins for Weekend Two after being excluded from the first weekend. That makes the open phase the first chance for a much wider group to see how the current multiplayer build feels before launch.
Early access is over; the public test is next
The cleanest way to think about the beta schedule is that the first weekend was a gated test and the second is the public one. Early access ran from August 21 at 11am PT until August 25 at 10am PT. The open beta starts three days later, on August 28 at 10am PT, and continues through September 1 at 10am PT.
PC Gamer's beta-date coverage independently confirms the same public weekend and the key point that players do not need to buy the game to participate in the open phase. That matters because beta access language can get messy once preorder bonuses, platform accounts and publisher promotions are mixed together. For Weekend Two, the headline requirement is simple: it is the open beta.
Activision also says additional content becomes available across the beta weekends. That can mean more maps, modes, equipment or progression opportunities depending on the schedule, but the important caveat is that this is still a test build. A beta is not a frozen launch version, and content, tuning and availability can change as the publisher reacts to technical data and player feedback.
Switch 2 joins the supported list
Nintendo Switch 2 is the notable platform change for the open weekend. Activision's August 21 guide lists it alongside the other supported platforms for Weekend Two after the system was not part of Weekend One. Players on Switch 2 therefore should use the open-beta schedule rather than older early-access details when planning when to download and play.
There is no need to fold later August 26 US posts into the story to understand the public weekend. The official beta guide already establishes the dates, access model and supported platforms that matter for players deciding whether to try it.
The main thing to watch after August 28 is how the build changes as the public population expands. More players means more matchmaking load, more hardware combinations and more feedback. Activision has not presented the beta as a final balance statement, so any weapon, perk, map or mode impression should stay attached to the version being tested rather than treated as a launch guarantee.
Players should also expect the usual beta rough edges. Matchmaking, queues, crashes and platform-specific issues can appear differently once the test is open to everyone. The useful feedback is the specific version, platform and situation where a problem occurred, not the assumption that every beta problem will survive into launch.
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