Understanding the Frontier Personal Item Size policy can help you save money and travel with ease. Frontier Airlines allows one free personal item per passenger, provided it meets the 14″ x 18″ x 8″ size limit. The Personal Bag Size Frontier must fit under the seat and can include items like a small backpack or laptop bag. Bags exceeding these Dimensions for Personal Item Frontier are considered carry-ons and come with extra fees. To avoid unexpected costs, measure your bag before heading to the airport. Following these guidelines will ensure a seamless travel experience with Frontier Airlines.