If you've received a travel credit for a canceled Delta Air Lines flight, you might be able to claim it as a cash refund, with interest.

As part of a class action settlement, Delta customers with canceled flights between March 1, 2020, and April 30, 2021, are entitled to a full cash refund, rather than the travel credits they likely received.

The lawsuit alleges that the airline breached its contracts of carriage by refusing cash refunds for flights canceled during the Covid-19 pandemic. While Delta denies wrongdoing, the company agreed to settle the lawsuit to avoid further litigation.

"Delta does not admit or acknowledge it failed to follow its contract of carriage or that it failed to provide refunds in accordance with its contract of carriage," the airline said in a statement provided to CNBC Make It.

"Since the beginning of 2020 we've refunded over 11 million tickets totaling $6 billion, of which 20% took place in 2022," the statement says.

How to claim your cash refund

To qualify for a cash refund, you must be a U.S. citizen who requested a refund through Delta's customer service department after your flight was canceled.

If you did not receive a refund or were given a travel credit, Delta owes you a cash refund worth the full or unused amount, provided that it was not used as of Jan. 13, 2023. The refund includes an additional payment of 7% interest on the original ticket price.

If you had multiple flights canceled between March 1, 2020, and April 30, 2021, you can claim a refund for each one.

To claim a refund, you are required to submit a claim form through the class action's website. You can submit a claim by mail, sent to an address posted on the website. Claim forms must be postmarked or submitted online by Sept. 15, 2023.

To prove that you made the purchase, you'll need to include documented evidence, ideally a receipt that shows flight information, including the date of the flight.

It's not yet clear when refunds will be issued. An Oct. 5 court hearing is scheduled to approve the settlement, so payments will not be sent out before that date.

If you're not sure whether you're an eligible claimant, you can call the settlement administrator at 1-888-814-6501, or email info@AirlineTicketSettlement.com.

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