Until recently, the only thing that auctions and airlines had in common were crowds of on-edge people in confined spaces. Some carriers are testing out the idea of turning their airport gates into auction houses, selling off premium seat upgrades to the highest bidders.

The Wall Street Journal reports that more than 30 airlines around the world, including several domestic airlines, are dipping their toes in the auction world by pitting passengers against each other for the pleasure of buying upgrades for first-class, business-class or premium-economy seats.

Auctions offer airlines an option to sell upgraded seats to passengers instead of offering the seats for free when it’s time to board.

For the passenger, the WSJ reports, the winning bids are often less costly for travelers than buying a premium ticket in the first place.

One traveler tells the WSJ that he’s taken advantage of the auction system with KLM Royal Dutch Airlines, paying no more than $430 for a business-class upgrade.

In all, he says keeping the bid below $500 makes his total trip cost about $1,600, less than half of what buying a business-class seat outright would set him back.

In the U.S., Virgin America is currently testing the SeatBoost auction at gates in Las Vegas an hour before the flight departs.

Under the system, bidding starts at $10, $30, or $50 depending on the length of the flight and whether passengers are bidding on extra legroom in coach or first-class. Passengers can see the bids via a leader board posted by the gate.

Just before boarding the airline awards one upgrade to Main Cabin Select and one to first. The airline wouldn’t disclose how much winning bids average, but said the process is competitive.

While the auctions provide another way for airlines to make a few bucks through upgrades, Virgin America tells the WSJ that it still provides top-level elite passengers with upgrades and sells upgrades through airport kiosks and its gate agents before the auction gets underway.

For now, the airline says it’s too early to know if the auction option will continue after the testing phase in Las Vegas.

American Airlines has also dabbled in the upgrade auction arena, but suspended the tests when the company integrated its reservation system with US Airways.

“It is something we would like to revisit for further assessment,” a spokesman tells the WSJ.

Reps for United Airlines and Delta say the companies are keeping an eye on the auction systems.

Going Once, Going Twice: Airlines Auction Seat Upgrades [The Wall Street Journal]

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