Under some circumstances, Frontier Airlines permits customers to cancel their flights. The following rules must be understood in the event that you must cancel your reservation. Passengers with refundable tickets have the option to postpone their flights and obtain a full refund in the form of the original payment. However, does not provide cash reimbursements if the ticket is non-refundable. Instead, they offer vouchers for credit that can be applied to future travel within 90 days of the cancellation date.