You’re waiting at a crowded gate to board your flight, when suddenly, you hear it. “Flight XYZ is overbooked; do we have any volunteers willing to give up their seat in exchange for a travel voucher?” But before you volunteer yourself as tribute in the airline Hunger Games, make sure you understand exactly what kind of restrictions might come with that voucher.

While every airline has different policies on this front, some may be more restrictive to to others. Spirit Airlines, for example, requires travelers to book their flights within 60 days of receiving a voucher. The industry standard, however, is a year, writes Christopher Elliott.

One of Elliott’s readers explained that they and their travel companion had volunteered to give up their seats on a recent Spirit flight in exchange for four vouchers. An airline rep told them these vouchers could be used to travel “anywhere” Spirit flies at “anytime.”

Though the reader asked about restrictions and booking several times, the agent confirmed that they could fly anytime, but would have to call to book the new flights within 60 days.

The travelers received six vouchers in the end, so they called the airline with several dates in February, March, April, May, and June they wished to travel — and were told that no voucher seats were available on any flights to their chosen destinations, not on any weekend in any of those months.

“We were able to book two of the six vouchers, but I feel like we were scammed, because we can’t use the other ones,” the reader wrote.

Elliott notes that while the gate agent should’ve fully informed the travelers about the vouchers’ restrictions, because when it comes down to it, it doesn’t matter what an employee says, it matters what the voucher says.

A representative for Spirit told Elliott that while the vouchers do have some restrictions, “they are not typically such limited options,” adding, “I completely understand their frustration.”

Spirit canceled the original vouchers and has now issued new-round trip coupons with fewer restrictions. But of course, that won’t be the case for every confused traveler, so make sure you do your research before you step up to volunteer.

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