Allegiant Air check in is the procedure used by customers of the budget American airline to confirm their attendance for a flight and acquire their boarding cards. You can do this in a number of ways, including at the airline counter, at self-service kiosks at the airport, or online via the airline's website or mobile app. Normally, passengers check in at the airport with their reservation details, seat selections, and any required travel documents. Visit- https://airlinespolicy.com/check-in-policy/allegiant-airlines-check-in/