Overbooking flights is one of airlines’ peskiest practices. Many airlines intentionally oversell tickets to account for no-show passengers. When they miscalculate, resulting in more passengers than available seats, travelers run the risk of being bumped. Officially, this practice is called involuntary denied boarding.
No airline wants to bump passengers. First, they’ll ask for volunteers to give up their seats in exchange for a later flight, flight voucher, or monetary compensation. Involuntary denied boarding occurs when there are not enough volunteers. It’s up to the airline to decide who gets bumped, considering factors such as fare class, check-in time, and frequent flier status.