Southwest Airlines remains one of the few major carriers to operate a large fleet of Boeing 737-700 aircraft, even as other airlines have retired the model in favor of larger and newer variants. The 737-700, which entered service in 1998, has become central to Southwest’s operations due to its compatibility with the airline’s single-type fleet strategy and its ability to efficiently serve medium-haul and lower-demand routes.
The airline has acquired more than 300 Boeing 737-700s over the years, which has allowed it to benefit from economies of scale and maintain flexible scheduling. While the aircraft offers lower capacity and less favorable seat economics compared to the Boeing 737-800 and MAX 8, it fits well with Southwest’s frequency-led, single-class service model. The 737-700’s short-field performance and lower seat count make it suitable for serving thinner city pairs and off-peak periods, helping Southwest manage demand and maintain profitability on routes that may not support larger jets.
Fleet commonality is another advantage for Southwest. Operating only Boeing 737s allows the airline to streamline pilot training, maintenance procedures, and spare parts inventory, reducing operational costs. “The aircraft anchors the Southwest Airlines single-type operating model. Pilots, spare parts, aircraft tooling and maintenance procedures can be aligned across the airline’s fleet. This allows the Boeing 737-700 to flexibly swap aircraft and protect network completion factors,” according to the airline.
Other carriers have shifted away from the 737-700 as their business models have moved toward higher-capacity aircraft to maximize revenue at slot-constrained airports and offer more premium seating options. In contrast, Southwest’s approach relies on frequent departures with smaller jets to provide more travel choices throughout the day.
Currently, Southwest operates 308 Boeing 737-700s and has 274 Boeing 737 MAX 7s on order, according to fleet data provided to Simple Flying by ch-Aviation. The MAX 7 is expected to replace the 737-700s starting in 2026, following certification by the Federal Aviation Administration. Southwest aims to transition to an all-MAX fleet by around 2031, though this timeline may be affected by certification delays and production challenges.
Looking ahead, the airline faces uncertainty about future fleet renewal, especially as the Boeing 737 line is not expected to have a direct successor after the MAX series. “The more likely option for Southwest is that it will renew its fleet with whatever new model Seattle-based planemaker Boeing brings to the table. This kind of aircraft will likely be light, offer next-generation capabilities, and serve as a natural stepping stone for legacy Boeing 737 operators,” the airline stated.
Southwest’s reliance on the 737-700 reflects its unique operational model and network strategy, setting it apart from other major airlines as it navigates future fleet transitions.
