Owned by Fox, Tubi is arguably the leader in free streaming. They have massive deals with studios like Paramount, MGM, and Lionsgate.
Many people overlook the official "Movies & TV" section on YouTube. They have a dedicated "Free with Ads" category.
Owned by Paramount Streaming, Pluto TV functions differently than most. It offers "Live TV" channels (dedicated channels for specific franchises or genres) alongside an On-Demand library.