Yes, Frontier Airlines typically charges a fee for missing a flight. The specific amount can vary depending on factors such as the type of ticket purchased and the fare rules. In most cases, passengers who miss their flight without canceling or rescheduling in advance may incur a fee. This fee can be substantial, potentially equivalent to the cost of the original ticket or a percentage of the fare. It's advisable to check Frontier Airlines policies regarding missed flights before booking and to communicate any changes or issues promptly to avoid additional charges.