You won't need a Game Pass subscription, but you'll need to watch some pre-roll advertisements
Xbox is reportedly close to announcing a new ad-supported version of its game streaming service. Apparently, Microsoft has been internally testing ad-supported cloud streaming with employees, letting them play games without a Game Pass subscription.
On October 3, The Verge reported that sources familiar with Microsoft's future plans have confirmed with the outlet that the tech giant will soon announce a new way to stream Xbox games without a Game Pass subscription. Currently, you need a Game Pass subscription to stream Xbox games. This new free streaming option will reportedly feature pre-roll ads that will appear before playing a game. Sources with knowledge of the internal testing of the service say these ads are about two minutes long. There's also a limit of one hour per session and about five hours max a month, though this might change if and when the service is rolled out to the public.