As of 2015, carry-on bags for Frontier Airlines must be no larger than 24 inches tall, 10 inches wide and 16 inches long, including handles, wheels and straps. Carry-ons cannot be heavier than 35 pounds. Bags that exceed the limitations are subject to extra charges.
Frontier Airlines charges varying fees for carry-on bags, depending on the type of ticket purchased, and when the traveler finalized the purchase. For instance, Frontier charges customers who purchase tickets via the web or 24 hours before departure $30 per bag. Customers who purchased tickets through a call center pay $35 per bag, while customers who made purchases at an airport ticket counter or self-service kiosk pay $40 per bag. Purchases made at the departure gate are subject to a $60 charge per bag.