Spirit Airlines shut down operations early May 2, canceling all flights and forcing travelers to find other ways to reach their destinations. Spirit said on social media it could not help passengers rebook on other airlines, though refunds would be available immediately for tickets bought through Spirit’s website with a credit or debit card.

The U.S. Department of Transportation said several carriers agreed to support affected customers, mostly through discounted or capped rescue fares on routes where they competed with Spirit. In many cases, passengers need to show a Spirit confirmation number and proof of payment or a canceled ticket to qualify.

What to know now: Your Spirit flight was canceled. How do you get a refund?

Details vary by airline, including how long the offers last, where they apply and whether travelers must book online or at the airport.

According to the Department of Transportation, United, Delta, JetBlue and Southwest are among the airlines capping ticket prices for Spirit customers who need to rebook canceled trips.