Ancillary Revenue refers to the income airlines generate from products and services sold in addition to the base airfare. These include services such as checked baggage, seat selection, priority boarding, lounge access, onboard Wi-Fi, meals, travel insurance, and partner offerings such as hotel bookings, car rentals, and other travel-related services.

As airlines continue to adopt modern retailing strategies, ancillary revenue has become an essential component of the customer experience, allowing travelers to personalize their journey while enabling airlines to diversify revenue beyond ticket sales.