Pet Travel on Frontier Airlines: Fees, Carrier Sizes and Rules (2026 Guide)

Pet travel on Frontier Airlines means flying a small domesticated pet in an under-seat carrier in the cabin on a flight within the United States, for a fee of $149 per pet, per direction, according to Frontier Airlines' Optional Services page (checked October 2026). Frontier does not carry pets as checked baggage or in cargo, accepts only trained service dogs on international flights, and caps soft-sided carriers at 18 x 14 x 11 inches.

This guide is current as of October 2026. Airline fees and rules change often, so every figure below names its source, and you should recheck Frontier's official pages before you book. It is written by the Animal Passport editorial team, and the last section explains how airline pet paperwork differs from the Animal Passport biometric livestock ID product.

Frontier Airlines pet policy at a glance

The table below summarizes Frontier's published rules for cabin pets and trained service dogs. It is built from Frontier's Family & Pets page, its pet FAQ, its Special Services page and its Optional Services fee schedule, all checked in October 2026.

How much does it cost to fly a pet on Frontier?

Frontier lists its "Pet Charge" as $149 per pet, per direction (non-refundable) on its Optional Services page, checked in October 2026. A round trip with one pet therefore costs $298 in pet fees, on top of your fare and any bag or seat fees.

Sources disagree here. At least one third-party guide, Zoomies Zone's Frontier page (last updated March 2026), still lists $99 per pet, per direction. Frontier's own fee page is the primary source and shows $149, so budget for $149 and confirm the figure at booking.

Frontier's Family & Pets page says the one-way charge can be paid in advance during booking. If you do not prepay, you pay when you check in your pet at the airport.

Does the pet carrier count as a carry-on?

The carrier counts as one of your items, but you keep a second one. Frontier's Family & Pets page says that in addition to the pet's travel container you may bring either a personal item (8 x 14 x 18 inches) or a carry-on bag (10 x 16 x 24 inches), and the carry-on bag costs extra.

Which pets can fly on Frontier Airlines?

Frontier's pet FAQ says it accepts domesticated dogs, cats, rabbits, guinea pigs, hamsters and small household birds on flights within the U.S. Domesticated dogs and cats must be at least 8 weeks old.

Frontier says it never accepts the following species:

• Large birds, such as parrots, macaws, cockatoos and birds of prey
• Rodents, including mice, rats and squirrels
• Beavers and ferrets
• Reptiles (including snakes) and amphibians
• Spiders and insects

Each passenger may bring one pet in the cabin, and only one adult dog or cat may travel per container. A passenger traveling with a trained service dog may also bring one pet, provided both sets of requirements are met, according to Frontier's pet FAQ.

Can pets fly in cargo or as checked baggage on Frontier?

No. Frontier's pet FAQ states, "we do not transport pets in the cargo hold," and that checked pets are not allowed. If your animal is too large for an under-seat carrier, Frontier is not an option unless the animal qualifies as a trained service dog.

Frontier pet carrier size requirements

Frontier's carrier rules, from its Family & Pets page and pet FAQ, are:

• Soft-sided carrier maximum: 18 inches long x 14 inches wide x 11 inches high
• Hard-sided carrier maximum: 18 inches long x 14 inches wide x 8 inches high
• Frontier recommends soft-sided carriers
• The pet must be able to stand, turn around and lie down in a natural position
• The carrier must fit under the seat in front of you
• The pet must stay inside the carrier at all times, at the airport and on board

Height is the limit that rules out most carriers. The 8-inch hard-sided cap is low, which is why Frontier steers travelers toward soft-sided bags that compress slightly under the seat. Frontier does not publish a weight limit for pets. The practical limit is that your animal must fit comfortably in a carrier of these dimensions.

Frontier also says you may not sit in row one or an exit row with a pet. Some other seats may not fit a pet container either, and Frontier says it will work with you to find a seat with space.

How to book pet travel on Frontier Airlines: step by step

1. Confirm the route is domestic. Frontier's pet FAQ says pets fly only on flights within the U.S.
2. Check species and age. Make sure your animal is on Frontier's accepted list and, for a dog or cat, at least 8 weeks old.
3. Measure your carrier. Stay within 18 x 14 x 11 inches (soft-sided) or 18 x 14 x 8 inches (hard-sided).
4. Add the pet to your booking. Select "Cabin Pet" in the Passenger Info section while booking, or later go to Manage Trip and choose "Add Pet in Cabin," per Frontier's pet FAQ.
5. Pay the $149 one-way fee online at booking or at airport check-in.
6. Check destination health rules. Ask your veterinarian whether your destination state requires a health certificate.
7. Avoid seats in row one or exit rows when you choose your seat.
8. Plan food and water. Frontier recommends no food or water for pets within four hours of departure and asks that you do not feed or water your pet on the aircraft.
9. Arrive early for TSA screening. You will need to take your pet out of the carrier at the checkpoint (see below).

Do you need a health certificate to fly a pet on Frontier?

For domestic cabin pets, Frontier does not require one. Its Family & Pets page says, "we do not require a health certificate for pets carried in the cabin traveling within the U.S.," but adds that a certificate "may be required by the specific state in which you are landing." Frontier notes that the United States Department of Agriculture (USDA) regulates pet transport within the U.S. and makes owners responsible for meeting destination laws.

Frontier's page also lists separate entry rules for Puerto Rico and the U.S. Virgin Islands, including rabies vaccination within six months of travel and a health certificate. Puerto Rico requires the certificate to be valid for 30 days and treatment for external parasites within 72 hours of entry. If you are flying to either territory, read that section of Frontier's page and confirm with Frontier that your flight accepts pets.

Frontier also says most veterinarians advise against sedating pets for air travel, because the effects of tranquilizers at altitude are unpredictable. It adds that no oxygen will be given to a pet in an emergency. Talk to your own veterinarian about your animal's fitness to fly; this article is not veterinary advice.

Can you fly internationally with a pet on Frontier?

Not with a pet. Frontier's Family & Pets page says it "will not accept new pets for International Travel" and accepts only service animals internationally. Frontier says every service dog on an international flight needs:

• A Centers for Disease Control and Prevention (CDC) Dog Import Form receipt
• A minimum age of 4 months
• A healthy appearance on arrival
• Proof of a microchip that a universal scanner can read

The CDC is the main authority for dogs entering or returning to the United States, according to the USDA Animal and Plant Health Inspection Service (APHIS) pet travel page (last modified March 2026). The CDC's "Bringing a Dog into the U.S." page (August 2024) says the rules depend on where the dog was vaccinated and whether it has been in a country at high risk for dog rabies during the previous six months. For travel out of the U.S., USDA APHIS advises contacting a USDA-accredited veterinarian as soon as you decide to travel.

Service dogs and emotional support animals on Frontier

The U.S. Department of Transportation (DOT) changed the federal rules in its December 2020 final rule, "Traveling by Air With Service Animals," under the Air Carrier Access Act (ACAA). The rule defines a service animal as a dog "individually trained to do work or perform tasks for the benefit of a qualified individual with a disability." It lets airlines treat emotional support animals as pets and cap each passenger at two service animals.

Frontier follows that rule. According to its Special Services page:

• Only dogs are accepted as trained service animals, including fully trained psychiatric service dogs
• Each passenger with a disability may bring up to two service animals
• Service animals in training and dogs under 4 months old are not accepted
• The dog must be harnessed, leashed or tethered at all times, and you cannot sit in an exit row
• As of February 1, 2021, Frontier no longer accepts emotional support animals on board; they may fly under the pet policy for a fee

The DOT Service Animal Air Transportation Form

Frontier requires the DOT Service Animal Air Transportation Form, which attests to the dog's health, behavior and training. If you booked more than 48 hours before departure, Frontier says you must submit the form at least 48 hours before travel. If you booked within 48 hours of departure, Frontier's two pages differ slightly: the Special Services page says to give the form to a customer service agent when you arrive at the airport, while its documentation portal says to present it at the departure gate. Have it ready at both. Frontier's service animal documentation portal says a typed PDF gets an instant decision, while a handwritten form can take up to 7 days to process. Bring a copy, because staff may ask for it at the airport or on board.

Going through TSA security with a pet

The Transportation Security Administration (TSA) screens cabin pets at the checkpoint, not in the X-ray machine. TSA's FAQ says to remove your pet from its carrier, send the empty carrier through the X-ray, and remove the leash when carrying your pet through the metal detector. In a March 2023 news release, TSA said pets should never go into the X-ray tunnel, and that a TSA officer will swab the owner's hands for explosive traces. It also said nervous owners can ask an officer for private screening and should put the pet back in its carrier away from the checkpoint.

Practical tip: Use a harness instead of a collar for the checkpoint. A harness is harder for a frightened cat or small dog to slip out of in a busy terminal.

Frontier pet rules vs. Animal Passport: what's the difference?

The word "passport" causes confusion, so here is the distinction. Frontier's pet booking, the DOT service animal form, state health certificates and CDC dog import paperwork are airline and government requirements. None of them is issued by Animal Passport, and Animal Passport does not replace any of them.

Animal Passport is a digital animal and livestock passport built on muzzle biometrics: an animal's nose print, which is unique like a human fingerprint. A phone captures the muzzle image, and the record links the owner, breed, estimated age, body condition and vaccination history. The app estimates age from a dental photograph with a confidence score, and it gives a body condition score from 1 to 5 from a side-profile photo.

Its main use is proving livestock identity and ownership. In August 2025, Animal Passport was used in livestock flood rescue in Pakistan so farmers could reclaim their animals after paper ear tags washed away. Animal Passport is not a government-issued travel document, is not accepted by Frontier in place of any required form, and does not provide veterinary diagnosis or legal advice. For more on animal identity and travel documents, browse the Animal Passport blog.

Bottom line

As of October 2026, pet travel on Frontier Airlines works for small animals on U.S. domestic routes, in an under-seat carrier, at $149 per pet each way. Frontier offers no cargo or checked-pet service and no international pet travel. If your animal is too big, needs to fly abroad or is an emotional support animal, plan for another airline or another way to travel. Check Frontier's Family & Pets page and Optional Services page right before you book, because these fees change.