But even if you have to postpone an Allegiant flight, you can still get some money back. According to Allegiant Air's cancellation policy, clients who miss their trip may be given a voucher for a future journey. To get a voucher, though, you must pay a fee and cancel more than seven days before your trip. Normally, there is a $75 fee per segment (not per person) for changing or cancelling a flight. However, due to the COVID-19 epidemic, Allegiant has momentarily reduced this price to $25 each segment. You should decide if Trip Flex makes sense for you based on the normal Allegiant fare and the charge per segment to cancel. The extra cost to purchase a package with Trip Flex may be little if you also need to buy other add-ons, such a personal item or a seat preference.