First page Back Continue Last page Overview Text


Airline seat availability is much more complicated than just the question of whether the number of reserved seats equals the capacity of an aircraft. Airlines use seat availability as a way to dynamically adjust prices according to demand. Simplifying somewhat, each published fare is assigned a letter of the alphabet called a booking code, typically also the first letter of the fare’s basis code. The airline chooses the booking code for a fare based primarily on the fare’s cabin (coach, business or first) and the fare’s price.

Asked whether there are any seats available on a plane, the response an airline gives is not “yes” or “no” but rather a per-booking-code vector of seat counts. For example, in the figure the first flight has 1 F booking code and 4 H booking codes available; the second has no F’s and 3 H’s. To fly on these two flights using the H14ESNR fare (with booking code H), H seats must be available for both flights. They are, and up to 3 people could buy H fares, but a (cheaper) fare with booking code Q could not be used because no Q seats are available for the first flight.

Airlines do not usually publish seat counts higher than 9, so even when a plane is empty it is common to see F9 Y9 B9...