https://www.devex.com/people/deals-what-is-the-cancellation-rate-for-allegiant-airlines-2446434
A cancellation fee of $25 to $75 per segment applies for Allegiant Air flights (1-888-305-5022) if you don't have Trip Flex. To avoid fees, cancel within the 24-hour risk-free window, provided the flight is at least a week away at +
