Southwest extended its schedule from early March to early April last week. Sure it included a new city — Knoxville — but the real news was buried in the weeds. Even though capacity is basically flat in March vs last year, the underlying schedule has changed somewhat dramatically. There are now four connecting hubs for the airline in the middle of the country, and they all work together.
Of course, Southwest has plenty of other places that can and will connect traffic, but the four hubs that get restructured in March are Chicago/Midway, Denver, Nashville, and St Louis. These hubs now each have four banks during the day, two in the morning and two in the evening. Here’s how it looks with the times shown being the local times in and out of the hub:
Three of these hubs operate the same way. They have their first bank arriving from the east in the morning and then heading west from there. Then right after there’s an arrival bank from the west which connects to eastbound flights. Then there’s another bank arriving from the west in the early evening which connects east. Finally, there’s a late bank arriving from the east that goes west.
This makes sense, because it allows the early morning bank to take advantage of the east coast time zone while the late bank takes advantage of the west coast time zone. Midway, however, is a little different. It’s actually the same in the evening, but the morning banks are flipped.
The first bank of arrivals comes in from the west on the redeyes from the coast before 6am. Then between 6:30am and 7am there are a bunch of early arrivals from nearby cities. Those all funnel into an east coast departing bank that goes between 7:30am and 8:05am. Here’s a map with redeye arrivals in red, short-haul arrivals in gray, and departures in blue.
This is pretty different from what Southwest used to do. It previously had a much flatter structure throughout the day, though it did have some banking. Let me show you what I mean using Midway as an example. Here’s what it looked like this past March (on a Monday):
Chicago/Midway March 2025 Monday Flights By Hour
Data via Cirium
You can see there are some two big banks with a third later in the day that’s less balanced, all highlighted in blue. In the middle the flights are spread out fairly evenly. Now look at the plan for next March.
Chicago/Midway March 2026 Monday Flights By Hour
Data via Cirium
You can see four clear banks highlighted in red. Sure, there are still flights at all hours, but the connecting banks have been peaked. Not only have they been peaked, the cities involved have been fine-tuned. For example, take a look at the morning bank in Denver. Here’s what it looked like this past March.
March 2025 Denver Morning Bank
Maps generated by the Great Circle Mapper – copyright © Karl L. Swartz.
You can see that this bank flows in all directions. But next March? Not so much.
March 2026 Denver Morning Bank
Maps generated by the Great Circle Mapper – copyright © Karl L. Swartz.
This is now a truly directional bank that brings people in from the east and then heads to the west.
These four hubs will of course continue to serve local markets as always, but having the four of them work together means they can be more efficient and do a better job of pushing traffic over the various hubs at different times of day.
What does this mean in practice? I went ahead and looked at Sacramento in more detail. On a random Monday in March 2025 and the same in March 2026, Southwest has 14 daily flights to these four hubs. Nashville converts from an evening arrival to a redeye, St Louis sees no change as an evening arrival, Midway gets a second flight that is a redeye, and Denver drops from 11 to 10 daily.
Looking at connections within two hours beyond the four hubs (without serious backtracking), the number of individual flight options rises more than 18 percent vs the prior year. As in any schedule, there are a handful (3 cities) that no longer have connectivity and 4 that gain it, but of the remaining 53 markets, 24 see increases and 20 see no change. In other words, only 9 see a decrease — all lose just one flight option — and 2 of those have their own nonstops anyway (Austin and Baltimore).
Here’s a look at the map:
March 17, 2026 vs March 17, 2025 Sacramento Connections via the Four Hubs
Maps generated by the Great Circle Mapper – copyright © Karl L. Swartz.
Sacramento + the four hubs in black, flat in gray, up or new in green, down or gone in red
With better connectivity that uses the four hubs to create opportunity throughout the day and the introduction of redeyes, Southwest has turned into the thing it always preteneded it didn’t want to be… an airline well-equipped for connections.
Does that save the airline? Well, it probably doesn’t hurt, especially when you have to fill 175 seats on most flights as deliveries of smaller planes continue to be held up. It’s a positive development for people in those mid-size cities that Southwest really needs to win.
