Does frontier airlines allow pets On most Frontier Airlines flights, cabin pets are limited to small domestic dogs, cats, rabbits, guinea pigs, hamsters, and house birds. The pet is considered as carry-on luggage and needs to fit within a container that fits under the seat in front of you. Pets cannot be checked as baggage or cargo on Frontier Airlines; there is a fee per flight segment. Prior to making a reservation, it's crucial to confirm the precise policies because certain locations and overseas flights can have restrictions.