Trip Flex allows customers the flexibility to make unlimited changes to the date, flight or destination in their reservations, within certain guidelines, with no change fees or cancel fees assessed. Customers are responsible for any change in price for air, hotel, auto, attractions, etc. Funds remaining after changes to an itinerary will be applied as non-refundable credit voucher good for travel on Allegiant. All travel involving funds from an itinerary must be completed no later than one year from the date the original itinerary was booked. Trip Flex may only be purchased at the time of booking and cannot be added to pre-existing reservations.