FlixBus did buy out Greyhound in 2021.
FlixBus is not the exact same as Greyhound although FlixBus did acquire Greyhound in 2021 and now both Greyhound and FlixBus share a combined booking platform and also an expanded network across North America.
FlixBus provides marketing, booking and customer service, Greyhound operates under the FlixBus umbrella, although both FlixBus and Greyhound continue to exist as separate brands within the larger Flix North America entity.
So in a way FlixBus and Greyhound could be seen as the same actually, because they are owned by the same company now and if you're riding a Greyhound bus you're also catching a FlixBus since FlixBus owns Greyhound.
But they continue to operate in their own different brands.
The main difference between Greyhound and FlixBus, is that Greyhound is a brand and a historical bus network that is now owned by Flix SE, the same global travel-tech company that operates FlixBus.
And as of the year 2021, FlixBus acquired Greyhound, creating a unified, expansive network with over 1,600 destinations in North America.
While they both do share the same parent company, passengers of Greyhound and FlixBus may notice differences in amenities, with some users finding FlixBus coaches to be cleaner and more modern, while Greyhound coaches offer features like complimentary onboard TV and movies.
FlixBus is owned by Flix SE, which also operates FlixTrain, FlixCar, Kâmil Koç, and Greyhound Lines.
FlixBus operates buses or, in many cases, just handles marketing, pricing, and customer service for a commission, on behalf of bus operators.