as auctions become a new way airlines around the world are selling upgrades.

Here with the story is WSJ's Middle Seat columnist Scott McCartney.

Hi Scott, great to see you!

Good to see you Tanya.

So Scott, how widespread is this practice of auctioning off upgrades?

Well, it's becoming much more widespread there and now,

at least 33 airlines around the world that do this, some of the major European airlines,

some of the major Asian airlines, and it's starting to spread in the United States as well.

And so how do these auctions work exactly, do they happen at the gate?

Well, some do.

Most of them happen by e-mail in advance, and the airline can set how far in advance,

the airline can set when the auction ends,

and whether or not they're actually gonna award a business class seat.

For example, on a long-haul international flight, they may find that when they get to 24 hours before departure

that even though you're the winning bidder, they've sold all the seats and they're not gonna do it.

But in most cases, they do have empty seats to sell.

They would rather sell them than give them away to frequent flyers or to others,

and so the auction is a way to create excitement and get people to spend more money than they probably would otherwise.

I can certainly see that generating a little excitement.

Now, Scott, is this one way that airlines are trying to appease travelers now that

the free upgrade has essentially disappeared even for flyers with elite status?

Yeah, there're several things at work.

On most airlines with long-haul international flights, you don't get those business class upgrades for free.

They're gonna cost even top-level frequent flyers in miles or a dollars to get the upgrade,

but domestic upgrades on most airlines are free, at least for the upper tiers of the frequent flyer ranks.

The problem has been that by selling seats on discounted first-class fares by offering upgrades for fixed price at the kiosk,

airlines have done a lot more to sell seats, the lower levels of the frequent flyer tiers almost never get upgrades.

And so if you're 39th on the upgrade list and you know,

there is one company that's now offering an app where an airline in Virgin America started testing this.

You can have an auction at the gate, you're looking at that upgrade list, you know you're not gonna get an upgrade,

you get to participate in an auction at the gate against people standing there,

and there's a leaderboard, whose winning and that may be the only way you're gonna get upgraded.

Is that Plusgrade, the app you're talking about?

No, that's SeatBoost, Plusgrade does the e-mail setup that most airlines are using.

Virgin America is the only one doing SeatBoost now, they're only doing it on flights to and from Vegas,

they think that's a population that's prime for bidding and gambling.

Who are in the gambling mode for sure.

Now Scott have you spoken to a lot of travelers who've used these auctions successfully?

Yeah, some, more in the international arena, and you know, they really like it.

I mean there's a whole strategy to it for many frequent flyers,

people who aren't going to pay thousands of dollars for a business class seat,

but they do want the upgrade and they find that they can buy a cheap coach ticket

and strategize and ploy the upgrade well, and you know, one guy was winning about half of his auctions at a price

that ultimately cost him less than half the full price of a business class ticket.

Not bad, I guess like real gambling, you've got to know your limit and stick to it.

Alright Scott, thank you so much for that!