What is the best way to cram people into a tin can in the sky?
For five decades, Dallas-based budget airline Southwest made its reputation on its unique open seating policy. Savvy passengers who checked in early got to board early, too, lining up at distinctive silver stanchions to claim first dibs on whichever seat they preferred. The fairer-than-thou approach extended all the way into Southeast’s cabins: For years, the airline had no first-class seating, and all seats basically looked the same.
No longer! On Tuesday, Southwest Airlines officially inaugurated its new assigned seating policy, the last in a suite of changes that moves it closer to the mean of airline operations. Taken by itself, the new policy, which breaks passengers into boarding groups and loads them according to seat location, should be more efficient.
But unfortunately for optimization enthusiasts, Southwest’s new boarding plan comes with some asterisks—concessions that executives say will goose profits—that will likely make the process pokier than it could be.
First, a bit more about the new plan. In lieu of boarding by check-in time, passengers will enter the cabin by group. They’ll be assigned to those groups according to the Window-Middle-Aisle method, or WILMA for short: starting at the back of the airplane and moving forward, window seat holders get onboard first; then middle seaters, also starting at the back of the plane; then aisle. Airlines use the WILMA method because it reduces clogs in the aisle as people find their seats. It also gives window seaters time to stow their luggage before the next wave of passengers board the flight. United Airlines, which switched back to the WILMA method in 2023, says it shaves minutes off the boarding process—a big deal in a business where time is tight and equals money.
But the new Southwest Airlines process has some catches that will gum up the works. The company also inaugurated in the past year a more capitalist approach to air travel that gives more perks to frequent Southwest fliers, and passengers willing to spend more to board early or snag extra legroom. People who buy a new “priority boarding” fare get on first. Then top-tier frequent fliers, people who choose the most expensive “choice extra fare,” and those who have bought the airline’s new “extra legroom” sets. Then other frequent fliers, those who choose the next fare level, and credit card members. Then, finally, those bottom-of-the-barrel economy class folks.
Southwest believes all these extra complications will make the company more money. Just the extra legroom seats, which rolled out last May, should deliver an extra $1.5 billion annually by next year, Southwest Airlines president and CEO Robert Jordan told investors last fall. Plus, passengers really want assigned seats, the airline said when it announced the changes back in 2024.
Still, the frequent flier programs, credit card perks, and even baggage fee strategies are getting in the way of perfectly efficient boarding processes industry-wide, says John Milne, an engineering management professor at Clarkson University who researches airplane boarding procedures. Overall, these sorts of perks mean airlines are getting “generally worse” at loading people onto planes quickly.
“They’re trying to get the extra money—I understand that,” says Milne. “But it does slow things down. ”
