Flying Everything you need to know about Allegiants carry-on size. 7 min read Allegiant is an ultra-low-cost carrier in the United States, and it only allows passengers one free personal item. Carry-on bags cost an additional fee. Here’s what you need to know about Allegiant’s baggage policy, including carry-on size. Carry-on details . Allegiant only includes 1 free personal item per traveler . Carry-on bags cost extra. Carry-on bags can be up to 10 x 16 x 22 inches , including wheels and handles. Personal items must fit under the seat and stay within 7 x 15 x 16 inches. Pay for your carry-on during booking if you can – waiting until the airport can cost up to $75 per bag, per segment. In this article Allegiant carry-on size, weight and what’s included for free. Common Allegiant carry-on FAQs. Top three carry-on luggage tips for Allegiant. Allegiant carry-on size, weight and what’s included for free. Allegiant’s carry-on size – and Allegiant’s personal item size – are listed below.…