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James lives and breathes route development. Educated in Air Transport Management at Loughborough University and Cranfield University, James has a PhD in airline strategy. James was Market Opportunity Analyst at London Luton Airport and Chief Analyst at anna.aero. He taught airline strategy and economics to undergraduate and postgraduate students for five years and has worked closely with multiple carriers on route and market intelligence projects. He is based near London, UK.

There is no denying the fact that Southwest Airlines is increasingly adding more ultra-short flights to its network. Of course, they are effectively spokes to feed some of the hybrid operator's busiest connecting airports. Extremely few passengers fly locally, as it is much quicker to drive.

Between August 2026 and March 2027, one in every 81 of Southwest's flights will be under 125 nautical miles (232 km). Compared to seven years ago, the proportion has jumped from just one in every 286 services.

Southwest's 11 Shortest Routes

The carrier's full network between August 2026 and March 2027 was explored using Cirium Diio. This process identified that Southwest's average stage length across its entire map is 676 nautical miles (1,252 km). This is within the under two-hour sweet spot for aircraft productivity that has traditionally underpinned the airline's operations.

You might wonder about Southwest's links within Texas. The shortest of these is Houston Hobby Airport (HOU) to Austin. This route covers just 129 nautical miles (239 km) each way, and is marginally too long to be included. However, unlike the following entries, most of which are relatively new, it has been served for many decades. Then there's California, with the shortest route being from San Diego to Santa Barbara, covering 167 nautical miles (309 km). The first departure was on August 4, 2026.

Southwest Between DEN & COS

The increasingly evolving Southwest has now served this extremely short route (which appears to be the airline's shortest-ever link) for more than five years. The debut took place in 2021, amid the COVID-19 pandemic. Initially, four daily departures were available. However, between August 2026 and March 2027, three daily flights will exist, even on Christmas Day. 59% of these services will use the 137-seat Boeing 737-700.

In the 12 months to April 2026, the US Department of Transportation (DOT) shows that Southwest transported 276,789 passengers between DEN and COS. It was the carrier's 40th most-trafficked route from DEN, which is its busiest airport in various respects, including for passengers and flights.

Only 73.3% of seats were filled, which was below both Southwest's network-wide average (77.4%) and the carrier's average at DEN (80.3%). It was also lower than for United Airlines on the same airport pair (79.9%), partly as that airline often uses regional jets. Of course, as the load factor is only one performance measure, do not read too much into it. Southwest's offering is likely to play a relatively important role for its network contribution.

Introducing Flights From BWI To PHL

Covering just 78 nautical miles (144 km) each way, Southwest revealed flights between BWI and PHL earlier this year. The route, which is brand-new to the carrier's map, will take off on March 11, 2027, and will be served twice daily. Regular service existed until 2020, when American Eagle pulled out.

Just as American's offering was for connectivity via its PHL hub, Southwest is beginning this route to feed services via BWI. This is the carrier's third-busiest airport for flights and among its top facilities for transit passengers. Between May 2025 and April 2026, the DOT suggests that about 8.7 million of Southwest's BWI passengers connected to another flight there (nearly 24,000 passengers daily).