[18] In June 2021, FlixMobility GmbH raised $650 million in a Series G financing round at a valuation of US$3 billion from investors including General Atlantic, Permira, TCV, HV Capital, BlackRock, Baillie Gifford, and SilverLake.

[20][21] In 2016, FlixBus was accused by a German government agency of forcing its partners to make drivers work excessive hours at low wages.

[60] Unlike train services and trucks, buses do not pay any road toll in Germany; this was criticized as a "hidden subsidy" by some German politicians in the spring of 2015.

[61] bdo, an association of German bus companies, responded that buses pay for infrastructure use in the form of related taxes (on fuel, for example) while billions in subsidies are paid to national rail provider Deutsche Bahn.

[62] In August 2016, following the acquisition of Postbus, FlixBus had control of roughly 80% of the German long-distance bus market, a move criticised by various media outlets as a de facto monopoly and harmful to competition.