Once you have a confirmed flight booking, selecting or changing your seat is usually done through the "Manage My Booking" or "My Trips" section of the airline's website or mobile app. You will need your 6-digit confirmation code (PNR) and your last name to retrieve your itinerary. Once logged in, look for a "Select Seat" or "Change Seat" link, which will open a real-time seat map of the aircraft. In 2026, seat selection has become a major "ancillary" revenue stream for airlines; while some legacy carriers allow free selection for standard economy seats, many now charge a fee for "Preferred" seats (near the front), "Extra Legroom" seats (exit rows), or even any seat selection at all for those on Basic Economy fares. If you have elite status or are traveling in a premium cabin, these choices are usually complimentary. If the seat map shows as "unavailable" or "blocked," it may mean the remaining seats are reserved for airport control; in this case, you can try again during the 24-hour check-in window. If you still cannot select a seat, a gate agent will assign one to you upon arrival at the airport, though this often results in being assigned a middle seat.