American Airlines allows passengers to choose their seats during or after booking a flight. Seat selection can be done via the American Airlines website, mobile app, or by contacting their customer service. Options range from Main Cabin seats to Premium Economy, ensuring a comfortable journey for all. A variety of seats, like Preferred or Main Cabin Extra, offer additional legroom for a fee, while Basic Economy fares may automatically assign seats at check-in. To select a seat, simply log into your reservation, view your booked flights, and select “Choose Seats” under the desired flight details.