Southwest Airlines Passenger Confused By Repeated Issue With Seats

Southwest Airlines' new assigned seating policy led to a curious experience for one passenger who recently attempted to book two adult seats, plus a lap infant.

On the r/SouthwestAirlines subreddit, Reddit user LemonApplePlums described a potential glitch in Southwest's booking system.

An unexplained phenomenon

According to LemonApplePlums, every time they shifted their seats around on a "mostly empty" flight, the third seat in the row they selected immediately became occupied. The user says they tried "a couple of times for science."

"I am guessing there’s some algorithm that’s putting a solo traveler who didn’t purchase seat selection with us to fill the row? But I noticed there are other rows with only 1 or 2 occupied seats so why is it following us specifically?" the person asked.

"The wishful side of me is hoping it’s just blocking that 3rd seat because of our lap infant but I really doubt it. Has anyone seen this before?"

Reddit users offer potential explanations

Several commenters shared possible theories on why this was happening.

"They will block the seat as a courtesy until/unless the flight gets more full," one person suggested.

"You doubt it, but I suspect, even though we often criticize SW IT, they are somewhat holding an adjacent seat for your lap child that is next to you. Should the flight sell out that held seat would disappear, but it would prevent someone from taking it when other seats are available," a second person said.

""Southwest uses the Amadeus Altea CM system. There is a function in that system that automatically applies a soft block (called a Reserved block, indicated by an R on the internal seat map) to seats adjacent to certain eligible passenger types, loads permitting," a third commenter wrote. "A passenger with an infant associated to them is one of those eligible types."

"I saw someone post in another subreddit (I think) that they had two parents and two lap infants and they wouldn’t let them sit in the same row due to oxygen masks," a fourth person chimed in. "Maybe it has something to do with that? Although, I do think it still doesn’t make sense because if it were three adults and a lap infant that still doesn’t make sense for the masks."

"Same is happening to me. 2 adults and a laptop infant. I called and they said the seat is currently empty on their side so just ignore it. My flight is in the morning, so we shall see!" a fifth person added.

According to Southwest's Help Center, via Newsweek, "infants between the ages of two weeks and two years can ride as a lap passenger with another passenger 12 or older." Those infants do not require a ticket.

More on Southwest's new seating policy

Long known for its open boarding process, Southwest made the move to assigned seats on Jan. 27, 2026. The budget air carrier previously got rid of its "Bags Fly Free" policy last year.

Southwest asks travelers to choose from four fare categories: Basic, Choice, Choice Preferred, and Choice Extra. You can read more on these options here.