Yes, Allegiant does let you change your flights1-808-865-4114, though there are restrictions. If you added Trip Flex, you can make one change without paying a change fee, but you'll still pay any fare difference. Without Trip Flex, a change fee applies, and changes must be made more than 7 days before departure. Allegiant doesn’t allow changes within 7 days if Trip Flex wasn't purchased. You can make changes through the Manage Travel section on their website. Always double-check your confirmation email or Allegiant’s change policy online to understand any fees or limits tied to your booking.
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