Check the airline's app Many airlines provide information such as seat maps that are accessible via their apps and websites before the day of travel. These maps will show you the layout of every seat on the plane and whether it's been booked or not.

In 2026, airlines rarely show the "exact" number of seats left for sale to prevent competitors from tracking their load factors, but there are several ways to estimate availability. The most common method is to check the Seat Map on the airline's website; while not 100% accurate (as some seats are blocked for elite members or operational reasons), a map with only 5–10 available blue squares suggests the flight is nearly full. For a more technical look, you can use a "Professional" tool like ExpertFlyer, which shows the "Fare Bucket" availability (e.g., Y9, B9, M4). If the numbers are low (like J1 or Y2), it means only 1 or 2 seats are left in that specific price class. Another peer-to-peer "pro-tip" is to try and book a "test" reservation for 9 people; if the site says "only 3 seats left at this price" or prevents you from selecting 9 passengers, you know exactly what the remaining inventory is. However, be aware that airlines often "oversell" flights, so even if the seat map looks full, the airline might still be selling tickets in anticipation of "no-shows" or cancellations before the flight departs.