To check Spirit Airlines credit, Start looking for the "Vouchers and Credits" drop-down list on the flight purchase page and enter the 17-digit code you received when you canceled your ticket, then select go. At the time of booking, vouchers can be applied to a reservation. Future Spirit travel credits can only be used by the traveler to whom they were issued and have no remaining value after that use. Spirit travel credits are only valid during government holidays, so make sure your dates are eligible. Finally, your credit must be used within 60 days of being issued.