Flying Frontier With Your Dog: $149, Cabin Only, Domestic Only
Frontier has one of the roomier carrier limits in the US, 18 × 14 inches, but the rest of the policy is narrow: domestic flights only, cabin only, and a fee that you don't get back. Here's the short version, checked September 2026. Confirm on Frontier's own pet page before you book.
In the cabin: a bigger bag than most
Frontier publishes no weight limit for dog and carrier together, only the bag size.
- Soft-sided carrier: max 18 × 14 × 11 in (45.7 × 35.6 × 27.9 cm).
- Hard carrier: max 18 × 14 × 8 in (45.7 × 35.6 × 20.3 cm).
- How many: one pet per passenger; someone travelling with a trained service dog may bring one pet as well.
- Age: at least 8 weeks old for dogs and cats.
The carrier goes under the seat in front of you and your dog stays in it for the whole flight. It has to be able to stand up, turn around and lie down in there. Besides dogs and cats, Frontier also takes rabbits, guinea pigs, hamsters and small household birds.
What it costs
$149 per pet, each way, and it is non-refundable. Note that this is on top of your baggage: with Frontier a carry-on bag is paid separately anyway.
Domestic flights only
Frontier does not accept pets on international flights. Only service dogs that meet the CDC rules can travel internationally.
No hold, no cargo
Frontier states that pets can't be checked as baggage and are not carried in the cargo hold. So a dog that doesn't fit under the seat can't fly Frontier at all. Our comparison of 27 airlines shows which airlines do take bigger dogs in the hold.
Breed rules
Frontier publishes no breed restrictions, just the list of species it accepts. With no hold, the snub-nosed bans other airlines use don't apply here.
On board
You can't take row 1 or an exit row with a pet. The carrier has to stay closed and under the seat, so plan a long walk before you check in.
Does your dog fit?
Our free Dog Flight Checker takes your dog's weight and tells you whether Frontier, and 26 other airlines, take it in the cabin or the hold. It works out the bag your dog actually needs to lie stretched out.
Also flying with: Southwest · American Airlines. Need a bag? Which Dog Carrier Bag Is Really Airline-Approved?
Source: Frontier Airlines family and pets pages and optional services fee table, checked September 2026. Always confirm with the airline before you book.