No traveler wants to be bumped from a flight—but what if you were offered $1,500? What about $10,000?

For some, the decision is a no-brainer. Eight travelers onboard an overbooked Delta flight from Grand Rapids, Mich. to Minneapolis, Minn. walked away $10,000 richer after they were asked to give up their seats in late June. Some may call these travelers lucky—or opportunistic—but compensation for overbooking is actually a common practice. Travelers at New York’s LaGuardia Airport were offered up to $3,000 this summer to deplane their flight to West Palm Beach, Fla., and it’s being reported at airports all across the world.

Disruptions in air travel are nothing new, but the amount of money airlines have offered impacted passengers has skyrocketed this year. By law, the compensation rate typically varies between $775 and $1,550 depending on the price of the traveler’s ticket and length of the delay, though some airlines are choosing to go well beyond these baseline figures to avoid PR nightmares.

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The practice of overbooking flights has drawn the ire of many travelers despite the hefty rewards. Google searches for “expected flights delays tomorrow” increased more than 400% in early June, and travelers have vented on social media about missing connecting flights or scheduled engagements because of overbooking.

Here’s what you need to know about the contentious airline practice and how to navigate it.

Why do airlines overbook flights?

It boils down to maximizing profits. Airlines want to make sure that every flight is as full as possible in case travelers cancel their tickets at the last minute or don’t show up—a common occurrence for airlines, since weather delays often force travelers to miss connecting flights. Airlines resort to overselling flights as a way to recover the costs of those empty seats.

But it doesn’t always work out. Between January and March 2022, 7,143 people who held confirmed reservations were involuntarily denied boarding from a flight because of overselling—up from 742 over the same period in 2021 and 1,576 in 2020. Roughly 34% of those travelers were flying on Frontier Airlines, 32% on Southwest Airlines and 14% on American Airlines, according to the latest Air Travel Consumer Report. Delta Air Lines, United Airlines, Alaska Airlines and JetBlue Airways had the least reports among major airlines.

“Airlines make their best educated guess at how many people they think are going to show up for that flight based on historical standards,” Scott Keyes, the founder of Scott’s Cheap Flights, tells TIME. “It can end up backfiring if they’re wrong and aren’t able to convince volunteers to take the compensation they’re offering to take a later flight.”

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Airlines have been gambling on seat availability for years, regularly overbooking both domestic and international flights. The issue gained attention in April 2017, when a Kentucky doctor was knocked unconscious—bleeding—and violently dragged off a United Airlines flight that was overbooked after he was randomly selected to give up his seat but refused to do so because he needed to see patients the following day. Video recording of the incident went viral, prompting United to pay a hefty settlement fee around $140 million.

The backlash forced the air travel industry to modify its approach to overselling, now offering travelers far more money to avoid negative PR attention. But it hasn’t always worked out smoothly. One traveler wrote to Southwest Airlines on Twitter last week that an overbooked flight made their family miss a cruise vacation, and were only compensated with a $150 voucher since they were placed on a standby flight. Another customer told TIME that they only received a $150 voucher from American Airlines despite being told they would receive $825 worth of credit for giving up their seat on an overbooked flight from Fort Worth, Tex. to New York City. “I understand being 21 is grown but I was also by myself and that can be scary at times,” says Ka’nya Grace, who was placed on an alternative flight that arrived at her destination five hours late. “I felt like I was being played with and lied to by American Airlines.”

Airlines typically first ask travelers who aren’t in a hurry to give up their seats voluntarily in exchange for compensation, but if they are still overbooked, airlines can deny a passenger a seat on an aircraft based on criteria that it establishes, such as the passenger’s check-in time, the fare paid by the passenger, or the passenger’s frequent flyer status, according to Tomasz Pawliszyn, the CEO of AirHelp, a for-profit air travel rights advocacy company that helps people submit legal claims to get properly compensated for overbooked or canceled flights. For those hoping not to get bumped from a flight, checking in early could help them to avoid that scenario.

How to negotiate for the best compensation on an overbooked flight

Airlines are required by law to compensate travelers who don’t get to fly in the form of a check or cash, but the amount of money is largely discretionary. If your flight is overbooked and you’re willing to give up your seat, experts advise negotiating with airline staff to drive up your compensation package before accepting.

“Many times you can negotiate for things like a better flight, hotel vouchers, meal vouchers and lounge passes,” Keyes says. “A lot of people miss this when it comes to getting bumped from an airline, but it’s not a one way street. There’s a secret menu of options that airlines have at their disposal that they can offer you beyond money or credits.”

For instance, if you’re denied boarding, Keyes says to request airline staff make your replacement flight non-stop, or business class instead of economy, in addition to negotiating the money they offer. Not all airlines will be able to accommodate, but some may. “Like so many companies, airlines are profit-seeking corporations,” Keyes adds. “They’re not going to start out by offering $10,000. But when they’re desperate enough, they will.”

For overbooked U.S. flights that result in you getting to your destination more than two hours later, U.S. Department of Transportation rules stipulate that the minimum compensation rate is $1,550, or 400% of your one-way fare, whichever amount is lower. If your substitute transportation is scheduled to arrive at your destination between one and two hours after your original arrival time, the airline must pay you, at a minimum, $775 or an amount equal to 200% of your one-way fare—whichever is lower. Travelers who are bumped involuntarily and receive substitute transportation within one hour of their original scheduled arrival time are not required to be compensated.

More than 95% of Americans don’t know these laws, according to a recent survey from AirHelp. The number of travelers using AirHelp’s website is up over 50% compared to the last month, Pawliszyn tells TIME, and the number of customers seeking help filing compensation claims has doubled. “We see a significant increase in customers using our service,” he says.

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For travelers headed to Europe this summer, the law is slightly different. Travelers on flights that departed from countries within the E.U. are eligible for up to $700 per person in compensation for avoidable flight disruptions, including delays over three hours, cancellations or denied boarding due to overbooking.

“It’s a bit surprising when you think of it from a purely financial standpoint—why would airlines be offering $5,000 in compensation when under federal law, they’re only required to offer $1,550,” Keyes says. “But when you look at it from a PR perspective, the answer is very clear, because bumping people against their will makes them very upset as it should and can result in some pretty disastrous social media fodder.”