Some airlines are giving travelers another year to use travel credits before they expire

• United Airlines, American Airlines, and Delta Air Lines have extended travel credits into 2022.
• Travelers that have canceled flights during the pandemic now have an extra year to rebook.
• Airlines chose to give customers travel credits instead of refunds to maintain cash reserves.

Waves of flight cancellations last year resulted in airlines issuing credits or vouchers instead of cash, with the promise that they could be used for future travel once customers were ready. For many, those credits close to expiring, even though a lot of Americans are still not comfortable traveling.

Some US airlines are responding to travel-hesitant customers by extending the deadline for flights credits so that customers can have more time to plan trips, especially as most of the country still has not received a COVID-19 vaccine.

United Airlines travelers now have until March 31, 2022, to use their "future flight credits" from trips canceled because of the coronavirus pandemic. "Take advantage of your flight credit by booking a flight on or before March 31, 2022, for a trip within the next year," United told flyers in an email.

American Airlines is offering a similar policy for voluntarily canceled tickets during the pandemic. "Flight credit issued for flights voluntarily canceled by customers during the COVID-19 flexible period can be used for travel through March 31, 2022," the airline's website says. Credits usually expire one year from their issuance.

Delta Air Lines is letting flyers who had to cancel tickets booked before April 17, 2020, use their credits for travel until December 31, 2022, the longest of the big three US airlines.

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Airlines have also made it easier to book flights on their websites using the credits, though some trips require a phone call to the airline for the credit to be applied. Credits can often be used for extras like paying for seat assignments, if the flight doesn't use the full amount.

Flyers using their credits to make new bookings can also take advantage of new flexible cancellation policies. All three have largely done away with change and cancellation fees for most tickets, allowing customers to book a trip and change it at their desire if they're not ready to travel.

The only caveat is that the difference in fare has to be paid each time if the new trip dates result in higher fares. Basic economy tickets and some international flights are also not included in the scheme, though each airline is different.

More Americans have been taking to the skies in February and March, according to Transportation Security Administration data, than during most months in 2020. For that, airlines can thank an accelerated vaccine rollout and the passage of a stimulus bill that gave many Americans an extra $1,400 in their bank accounts.

Airlines chose to give travel credits instead of cash refunds at the pandemic's peak as they needed cash reserves to weather the pandemic. Cancellations exceeded bookings for most carriers once the coronavirus spread across borders and continents, and traveler numbers dropped to their lowest levels in decades.

Just over one year in, however, airlines are becoming cash positive once more.