Mixed cabin passengers refer to passengers who are arranged to sit in a higher cabin when economy class is oversold. Under normal circumstances, mixed passengers do not enjoy advanced catering and other services.

Mixed cabin means that after the airline flight controller sets the mixed cabin logo in the flight establishment stage, when selling a cabin, the system will check the remaining available seats higher than that cabin, and when there are no seats in the lower cabin, it will occupy the seats in the higher cabin, thus maximizing the seat utilization rate. No mixed grade sign is set, and when there is no vacancy in the lower cabin, stop sending overbooking information to the controller.

Mixing cabin is divided into mixing cabin check-in and mixing cabin sales. When the flight is about to take off and the economy class is oversold, the check-in staff will upgrade some passengers to the second class to ensure the passengers' travel. This is the so-called mixed-cabin check-in mixed-cabin sales. On the day before the flight takes off, the sales staff predicted that the economy class may be oversold and there are more seats in the two cabins, so they upgraded the economy class passengers with high discount to the two cabins in advance.

Mixed cabin passengers only enjoy two cabin seats, and the service and meals are the same as those of economy class passengers. Only upgraded passengers can enjoy the standard service and meals in the two cabins.