Here are the rules for Delta, American, JetBlue, United, and SouthWest.

What are flight credits?

Flight credits are essentially vouchers airlines give you when you cancel or change a flight, Neugarten says.

Online flight booking website provide modish reservation system

Person booking flight online.Credit:Ralf Hahn/Getty Images

Once issued, credits can be used in full or part toward future travel with the same airline.

Its usually under My Trips or Wallet, Neugarten noted.

Yellin noted, For most U.S. major airlines, flight credits can be applied online during the booking process.

Silhouettes of passengers waiting at an airport

People walking around an airport.Caroline Purser/Getty Images

A few airlines, including Delta, allow travelers to combine multiple flight credits toward one reservation.

Flight Credit Expiration Policies

Expiration dates are probably the most criticaland confusingaspect of flight credits.

Heres a detailed look at the policies for six major U.S. airlines.

Delta Airlines

Delta offerseCredits, which are typically good for one year from the issue date.

Travelers can also apply future flight credits toward some non-ticket items, like an upgrade to Economy Plus seating.

United flight credits are typically valid for a year.

The credits are easy to use as well.

It’s important to consider that different fare classes have slightly different rules.

American Airlines

Americans policies are abit more complexthan others.

The airline issues multiple types of credits, each with different expiration rules.

you’re free to reach the credit via your Travel Bank within your TrueBlue account.

Book now, change later.

you might shift dates later if needed.

That is one tip that we tell our members often that works super well.

Stay organized.

Double-check transferability terms.

Check for policy updates.

A lot can change within a year, especially in the world of travel.