One complimentary personal item is permitted per passenger on Frontier Airlines, provided that it does not exceed the airline's stringent 14" H x 18" W x 8" D size restrictions (including handles, wheels, and straps). This bag, which should fit beneath the seat in front of you, can hold a briefcase, laptop bag, purse, or small backpack. Should the personal item surpass these measureme... https://airlineterminalservice.com/blog/frontier-airlines-personal-item-size/