In the EU airlines have to compensate passengers who are denied boarding if the reason is that the flight is overbooked: https://europa.eu/youreurope/citizens/t

In the EU airlines have to compensate passengers who are denied boarding if the reason is that the flight is overbooked: https://europa.eu/youreurope/citizens/travel/passenger-rights/air/index_en.htm#overbooked https://europa.eu/youreurope/citizens/travel/passenger-right... The same applies for flights cancelled for operational reasons, and the airlines may end up having to book tickets with one of their competitors if the competitor have seats available.