Southwest Airlines fleet

As of March 2025, Southwest Airlines operates an all-Boeing 737 fleet with 801 aircraft, making it the fourth-largest commercial airline fleet in the world and the largest 737 operator. Additionally, as of October 2023, Southwest has nearly 500 Boeing 737 MAX aircraft on order. Southwest has only ever operated Boeing 737 aircraft, except for a brief period during the late 1970s and early 1980s, when they operated 6 Boeing 727-200 aircraft. The airline served as the launch customer of the 737-300, 737-500, and 737-700. The use of a single aircraft type across its fleet allows Southwest's pilots and flight attendants to operate any aircraft without restrictions and reduces training time and costs.