Southwest Airlines new premium seats featuring extra legroom.
Leslie Josephs/CNBC
Southwest Airlines' first assigned seats went on sale this week for flights starting Jan. 27 of next year. What you'll pay will vary.
The price depends on the route, when you're traveling and where you sit. Selecting your ideal seats can add hundreds of dollars to the cost of a family vacation, similar to flying on other airlines.
For example, a roundtrip ticket in the "Choice" ticket class — the second cheapest type of ticket — between Denver Airport and Orlando Airport leaving Feb. 14 and returning Feb. 21, which coincides with Presidents Day, was going for $692 on Southwest's website on Thursday. For seats the airline deems "preferred," it would be $46 for a window or aisle seat in Rows 7 to 13, or $41 for a middle seat in those rows.
Customers with elite frequent-flyer status on the airline or with Southwest Airlines credit cards will be exempt from some of the fees.
An extra-legroom seat, located in the first six rows of the Boeing 737 Max 8 aircraft, was going for $96 for window or aisle. Prices were similar, but slightly lower, for the return flight.
A Southwest Airlines seating chart for a Boeing 737 Max 8.
Seat selection in the back of the plane in rows 17 through 30 are free of charge for a "Choice" ticket. The more expensive "Choice Preferred" ticket includes preferred row seats, while the priciest option, "Choice Extra" includes extra-legroom seats and also comes with a free "premium" beverage like an alcoholic drink.
The same route, on the same days on United Airlines was $665, with extra-legroom seats varying from $105 to $126 each way and $37 to $42 for preferred seats.
The changes are all part of Southwest's plan to ditch the hallmarks of its more than half-century-old business model. For decades, that included open seating (and uniform legroom throughout the cabin) along with a quirky boarding system that led to a mad dash at the airport for a seat, and two free checked bags for all customers.
Southwest's rivals have made billions on bag and seat fees, raising questions for years from investors and Wall Street analysts about whether the carrier was maximizing revenue. Last year, activist hedge fund Elliott Investment Management took a big stake in Southwest, calling for such changes, and leading to a board shakeup. Major U.S. carriers brought in $12.4 billion assigned-seating fees between 2018 and 2023, according to Senate panel report.
Southwest's first-ever bag fees started with tickets sold in late May. The airline is charging $35 for a first checked bag and $45 for a second, roughly in line with other airlines.
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The carrier also joined rivals in launching a no-frills basic economy ticket, where customers don't get free, advanced seat selection, something Southwest expects it will benefit from next year, when seat assignments go into effect.
"We assume there will be a positive impact in Q1 when we go to assigned seat, that's a more compelling buy-up from basic economy to Choice," Andrew Watterson, Southwest's chief operating officer, said on an earnings call last week. "However, should we succeed in making it a positive before then, that's an additional tailwind as we go throughout the second half."
Southwest will reward its most loyal customers though, with choice seats as perks.
Frequent flyers with top-tier A-List Preferred status on Southwest will get extra-legroom seats at booking, as well as two free checked bags, and A-List status-holders can book them 48 hours before departure, though there is no guarantee they'll be available. Both groups will have complimentary access to preferred seats. Several Southwest credit cards also provide access to preferred seats, regardless of the fare type.