Major airlines akin to United, Delta and American Airlines suspended flights on Friday morning as a result of a worldwide IT outage that disrupted their operations and caused delays for travelers.

“You can imagine the huge chaos that is breaking out everywhere,” says Eric Napoli, general counsel at AirHelp, which helps airline passengers claim compensation for delayed or canceled flights.

“Any kind of standstill, the bottleneck [it has] on so many flights is incredible,” he added.

Passengers affected by flight disruptions may be entitled to a refund, a hotel or meal voucher, or other compensation.

But it depends heavily on the airline, say travel experts.

“There is this kind of gray area where we are at the mercy of the airline’s policies,” Napoli said.

There is actually only one guarantee for the financial obligation of an airline: the customers are a refund is owed of the ticket price (and fees) if the airline cancels their flight – regardless of the reason – and they choose not to travel on an alternate flight, according to the U.S. Department of Transportation.

This also applies to non-refundable tickets.

This means that customers will get money back for a canceled flight if they decide against the flight and also decline an alternative such as a rebooking or flight voucher, said John Breyault, a travel expert at the National Consumers League.

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Passengers would also be entitled to a refund in the event of “significant” schedule changes or delays and could choose not to fly, the Ministry of Transport said.

However, the Department of Transportation does not define what is “significant.” This determination is based on factors such as the length of the delay and the flight, as well as special circumstances, the agency said.

From 28 October, airlines can will have to “immediately” and automatically issue refunds to customers, due to a rule issued by the Biden administration in April. That rule also defines “significant” itinerary changes, including delays of three hours for domestic flights and six hours for international flights.

But because the rule doesn't take effect until October, it won't help customers affected by Friday's outage, who may have to “jump through hoops with the airline” to get a refund, Breyault said.

It could be even more difficult for passengers who did not buy their ticket directly from the airline but through a third-party booking website, experts say.

To receive financial compensation, customers will likely have to do business with that intermediary, Napoli said.

Expedia, for example, said: on social media On Friday morning, “as a result of a worldwide IT outage, there was a high volume of calls and long wait times. If your issue isn’t urgent, please postpone your call and chat to avoid long wait times.”

However, many travelers affected by Friday's power outage must or wish to fly to their final destination and are due to this fact not entitled to a refund.

In such cases, there is mostly no government guarantee for travelers. This is where the airlines' specific policies come into play.

“The airline will fly you to your destination on the next available flight,” said Sara Rathner, travel expert at NerdWallet.

“What could be different? [between airlines] is the amount of compensation you could receive retrospectively, not only for the delays but also for any other costs you may incur,” she added.

The website of the Ministry of Transport outlines the promises made by network operators to their customers in the event of cancellations or delays of more than three hours. (The dashboard includes the policies of ten major U.S. airlines and their regional operating partners, which handle 96% of domestic passenger air traffic.)

The airlines are obliged to keep these promises, the agency said.

All airlines commit to rebooking passengers on the same airline free of charge, some do so on a partner airline, and most offer a meal and/or hotel stay in the event of long delays or cancellations, Napoli said.

The airlines' obligations apply only to circumstances throughout the airline's sphere of control.

According to the Ministry of Transport, a “controllable” cancellation or delay of a flight could be due, for instance, to problems with maintenance or crew, cabin cleansing, loading of luggage or refueling.

It is mostly tougher for consumers to receive any form of compensation for uncontrollable events akin to the weather, Breyault said.

CrowdStrike, a cybersecurity company, experienced a major outage related to a technical update on Friday, affecting corporations like Microsoft as they scrambled to revive apps and services utilized by quite a few corporations, including airlines.

Airlines select their suppliers, Breyault said. One could argue that “a failure of one of their suppliers is controllable,” he said.

The Ministry of Transport actually The agency said on Friday that the delays and cancellations resulting from the system failure were a “controllable” event attributable to the airline.

“To find out what amenities your airline offers in the event of a controllable delay or cancellation, check its customer service plan on its website,” the DOT said.

Passengers should keep all receipts for unexpected costs incurred as a result of a delay or cancellation – akin to accommodation and meals – with the intention to have financial proof when making a claim with an airline or travel insurance company, for instance, advises Rathner.

“You may get some of the money back, so don’t throw away the receipts,” she said.