Here’s how to score a paid upgrade, according to two former flight attendants.

There are very few exceptions, so don’t expect to score afree upgradeby just asking.

The price difference is in the thousands, depending on the route.

Airplane seat in first class cabin

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There is also a team of flight attendants on board who would be aware of the ‘free upgrade.’

Start by contacting your airline after booking to see if there are any paid upgrades available.

If you’re out of luck there, you could loop back and try at the check-in desk.

View of back of gate agent checking in two passengers

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If it’s another no, you still have a chance.

This is when asking for an upgrade at the gate can work in your favor.

Chat with the gate agent just before boarding begins to see if a paid upgrade might be possible.

“Standard procedure is to wait until the door closes to see if everybody shows up for the flight.

If the seat is available, the passenger pays for the upgrade on the flight.”