Southwest Has A Secret “Infinite Legroom” Seat — Here’s Why It Exists And How To Grab It

Southwest Airlines has an infinite legroom seat that’s the most desirable on the aircraft. I’ve had the seat – even without an especially low boarding number – because it’s an exit row seat midway back in the aircraft and many people don’t know to make a beeline for it.

Founder of global logistics firm Flexport Ryan Petersen asks why this seat even exists

Why does Southwest have this one seat that’s so much better than all the rest? pic.twitter.com/I9HKDBs5t9

— Ryan Petersen (@typesfast) December 10, 2025

Southwest actually has two of these seats – 16A and 16F on their Boeing 737-800s and MAX 8s. This doesn’t exist on their 737-700s.

The exit itself is overwing at the row ahead (row 15). And to certify the plane, the FAA requires a clear passageway from the aisle to that exit, plus an “unobstructed space” around the exit where no seatback or structure can intrude (14 CFR 25.813(c)). There must be at least a 20-inch wide unobstructed path when there are three seats between aisle and wall, and no seatback allowed to impinge on the projected opening of the exit.

If Southwest put a normal window seat in the row immediately in front of the over-wing exit, that seat would sit right in the required egress area and would either:

• impinge on the 20-inch passageway from the aisle to the exit, or
  
• interfere with the overwing exit door operation and the evacuation “staging” space at the top of the wing.

The simple fix is to delete that window position in the exit row (what would be 15A/15F), keep two seats (B/C and D/E) there, and then put a full row behind it.

The result is that row-behind window (16A/16F) has no seat in front and looks like “infinite legroom,” because that space really belongs to the exit, not the passenger.

The obligatory @SouthwestAir shot… pic.twitter.com/hKG6y591yA

— gary leff (@garyleff) April 22, 2022

Here’s the thing: deleting that seat costs Southwest nothing. If they had a seat there, they would need to remove one somewhere else.

That’s because Southwest keeps its 737-800 and MAX 8 aircraft capped at 175 seats. The seat count doesn’t change, even as Southwest installs extra legroom seats (stealing legroom from other rows). Southwest used to be more generous than other airlines with seat pitch because they weren’t going to have planes with more than 175 seats.

That’s because the pilot union contract re-opens pay rates if Southwest operates an aircraft with more than 175 seats. So it’s economically irrelevant to Southwest whether there’s a seat at 15A or not, because if there was they’d remove a seat somewhere else.

Meanwhile, Southwest isn’t alone with the infinite legroom seats. I’ve flown them on American Airlines. And Delta has it on their 737, also – 21A/21F on the 737-900ER for instance.

Those windows sit directly behind a pair of over-wing exits and the associated clear-space zone, so the window position in front is omitted and the row behind ends up with nothing in front of it. As with Southwest, the driver is the overwing exit layout and access rules.

One commenter offers that “the missing seat was sucked out the door on a prior flight.” That is.. not what happened.

On Delta I grab this seat using my Air France KLM Flying Blue Gold status (obtained via Bilt Platinum). I get charged for ‘Comfort+’ extra legroom seats, but not for exit row seats. And on Southwest I have a strong shot with mere A-List status (currently from Chase’s Reserve card $75,000 spend threshold bonus). But for flights starting late January it’s something most will have to pay for via assigned seating in the booking flow, as they move away from their open seating concept.