The global software outage last week caused thousands of travelers flying in the United States and internationally to have their flights delayed, canceled or both. In the days that followed, some airlines were trying to reboot critical computer systems affected by the outage, with many of their passengers still stranded at airports.

During a travel meltdown, it may seem nearly impossible for air travelers to find immediate help. Gate agents are swamped, customer service phone lines have hourslong hold times, and seemingly confusing or incomplete instructions online only add to the headaches.

Passengers who foot the bill for last-minute lodging and other expenses are entitled to reimbursement if their flights were impacted by an event in the airlines’ control, like the CrowdStrike outage. Here’s how to get your money back.

If they caused the disruption, airlines owe passengers assistance

It is the airline’s fault when a situation under their control — issues with crew, maintenance, baggage and fuel, or software outages — leads to a delay or cancellation. Weather and air traffic control issues do not count. On Friday, the Transportation Department noted that this I.T. outage fell under the control of the airlines.

What passengers will get from airlines depends on how long they were forced to wait, but it could include transport to and from hotels and the costs of accommodation.

Know what you are owed, and ask for it

Strategize your ask. Gate agents may not always know the airline’s commitments or the Transportation Department policies. Usually, airlines prefer to take care of the details, distributing vouchers or directly booking hotel rooms. But during the CrowdStrike fallout, they initially did not believe they were required to provide assistance and later, seemingly, remained unaware of their obligations in some instances or were too overwhelmed by the numbers.