Frontier Airlines Policy for Pets in 2026: Fees, Carrier Size and Service Dogs

The Frontier Airlines policy on pets is the set of rules the ultra-low-cost U.S. carrier applies to animals on its flights. As of October 2026, it allows one small domesticated dog, cat, rabbit, guinea pig, hamster or household bird per passenger, in the cabin only, on flights within the United States. The fee is $149 per pet, each way (Frontier Airlines, 2026). The carrier can be up to 18 x 14 x 11 inches if soft-sided, and must fit under the seat in front of you. Frontier does not fly pets in cargo and does not accept emotional support animals.

This guide sets out the current rules from Frontier's own pages, the U.S. Department of Transportation (DOT) service animal regulation, and guidance from the United States Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) and the Centers for Disease Control and Prevention (CDC). It is written by the editorial team at Animal Passport, which covers animal identity and travel documentation. Rules and fees change often, so check Frontier's live pages before you fly.

Frontier Airlines pet policy at a glance (October 2026)

• Fee: $149 per pet, per direction, non-refundable (Frontier Airlines Optional Services, 2026).
• Where pets fly: In the cabin only. Frontier's pet FAQ (2026) says it does not carry pets in the cargo hold, and checked pets are not allowed.
• Routes: Domestic U.S. flights only. Frontier's Family & Pets page (2026) says it "will not accept new pets for International Travel."
• Limit: One pet per passenger, and only one adult dog or cat per carrier.
• Minimum age: Dogs and cats must be at least 8 weeks old.
• Carrier size: Soft-sided carriers up to 18" L x 14" W x 11" H. Hard-sided carriers up to 18" L x 14" W x 8" H.
• Service dogs: Accepted free of charge with the DOT Service Animal Air Transportation Form. Emotional support animals are not accepted as service animals.

Which animals does Frontier allow in the cabin?

According to Frontier's Family & Pets page (2026), domesticated dogs, cats, rabbits, guinea pigs, hamsters and small household birds may fly on flights within the United States. Dogs and cats must be at least 8 weeks old.

Frontier lists species it never accepts: large birds such as parrots, macaws, cockatoos and birds of prey; rodents, including mice, rats and squirrels; beavers; ferrets; reptiles, including snakes; amphibians; spiders; and insects. The airline adds, "please, no lions, tigers, or bears."

One detail surprises owners. USDA APHIS counts ferrets as pets for travel purposes (USDA APHIS Pet Travel page, updated March 2026), but Frontier bans them anyway. Whether the government recognises an animal as a pet does not decide whether an airline will carry it. The airline's own list applies.

How much is the Frontier pet fee?

The Frontier pet fee is $149 per pet, per direction, and non-refundable, according to the airline's Optional Services page as of October 2026. A round trip with one pet therefore costs $298 in pet fees, before any carry-on bag charge.

Frontier says you can pay the charge when you book. If you don't pay in advance, you pay it when you check in your pet. The pet fee does not replace your bag allowance. Under Frontier's Family & Pets page (2026), you may bring the pet carrier plus either a personal item (8" H x 14" W x 18" L) or a carry-on bag (10" H x 16" W x 24" L), and the carry-on costs extra.

Frontier pet carrier size and rules

Frontier's pet FAQ (2026) sets these carrier requirements:

• The carrier must be large enough for the pet to stand, turn around and lie down naturally.
• It must fit under the seat in front of you.
• Maximum hard-sided size: 18" L x 14" W x 8" H.
• Maximum soft-sided size: 18" L x 14" W x 11" H.
• Soft-sided carriers are recommended.
• Only one adult dog or cat per carrier.

Height is usually what rules a carrier out. The 3-inch difference between the soft-sided and hard-sided limits is why Frontier recommends soft-sided bags, which compress to fit under the seat.

Onboard rules for pets

Frontier's Family & Pets page (2026) adds these cabin rules:

• You may not sit in row one or an exit row when travelling with a pet.
• Your pet must stay in its carrier at all times, including if it becomes disruptive.
• Frontier asks that you not give food or water to your pet on the aircraft, and recommends no food or water within four hours of departure.
• No oxygen will be given to a pet in an emergency.
• Your pet must be "harmless, not disruptive, odorless, and require no attention during flight."

On sedation, Frontier notes that most veterinarians advise against it, because tranquilisers have unpredictable effects on animals at altitude. Ask your own veterinarian about your pet. Animal Passport does not give veterinary advice.

How to add a pet to a Frontier booking

1. Check your pet is eligible. Confirm the species is allowed, the animal is old enough, and the flight is within the U.S.
2. Measure your carrier. Include handles and pockets, and check it against the 18 x 14 x 11 inch (soft) or 18 x 14 x 8 inch (hard) limits.
3. Add the pet when you book. Select Cabin Pet in the Passenger Info section (Frontier pet FAQ, 2026).
4. Or add it later. Go to Manage Trip and select Add Pet in Cabin.
5. Check destination rules. Frontier says it is your responsibility to meet the laws of the state or territory you are flying to, including health certificates.
6. Choose your seat carefully. Avoid row one and exit rows. Frontier says some seats can't fit a carrier and it will help find one that can.

Service dogs vs. emotional support animals on Frontier

Since the DOT's final rule Traveling by Air With Service Animals (Federal Register, December 10, 2020; effective January 11, 2021), U.S. airlines may define a service animal as "a dog, regardless of breed or type, that is individually trained to do work or perform tasks for the benefit of a qualified individual with a disability." The same rule lets airlines treat emotional support animals as pets and limit each passenger to two service animals.

Frontier applies that rule fully. According to its Special Services page (2026):

• Only dogs are accepted as trained service animals, and fully trained psychiatric service dogs qualify.
• Each passenger with a disability may bring up to two service animals.
• Comfort, companionship and other animals that are not task-trained are not service animals.
• Service animals in training are not accepted.
• Service animals under 4 months old are not accepted.
• The dog must be harnessed, leashed or tethered at all times in the airport and on the aircraft.

An animal that does not qualify as a service animal may still fly under the pet policy, for the pet fee. Frontier also lets a passenger with a trained service dog bring one pet in the cabin as well.

The DOT Service Animal Air Transportation Form

Frontier requires the DOT Service Animal Air Transportation Form. On it, the handler attests to the dog's health, behaviour and training, including its rabies vaccination expiry date and veterinarian details. You submit the form to the airline, not to the DOT.

Timing depends on when you booked. If you booked more than 48 hours before departure, Frontier says the form must be submitted no later than 48 hours before travel. If you booked within 48 hours, Frontier's sources differ slightly. Its Special Services page says to hand the form to a Customer Service Agent at the airport, and its documentation portal says to present it at the departure gate. Bring a printed copy and arrive early.

Frontier's portal says typed PDF forms get an instant approval or decline, while handwritten forms can take up to 7 days to process. Keep a copy, because staff may ask for it at several points during your trip.

Comparison: pet, service dog and emotional support animal on Frontier

Sources: Frontier Airlines Family & Pets, Special Services and Optional Services pages (2026). DOT final rule, Federal Register (2020).

Health certificates, Puerto Rico and international travel

Domestic flights within the U.S.

Frontier says it does not require a health certificate for pets in the cabin on flights within the U.S. It warns that the state you land in may require one. Check that state's rules with your veterinarian.

Puerto Rico and the U.S. Virgin Islands

Frontier's Family & Pets page (2026) lists stricter rules for these territories. Every animal flying to or from Puerto Rico, including service animals, needs an official health certificate valid for 30 days. The certificate must show:

• that the animal did not come from an area quarantined for rabies;
• a rabies vaccination within six months before travel, for pets over four months old;
• treatment for external parasites within 72 hours before entry;
• official identification, either a microchip or a collar with a metal ID tag.

For the U.S. Virgin Islands, Frontier lists a health certificate showing the animal is not from a rabies-quarantined area, plus a rabies vaccination within six months before travel. Dogs and cats under 12 weeks old are exempt from the vaccination rule.

International flights: service dogs only

Frontier no longer accepts new pets on international flights. Service dogs may still fly internationally. According to Frontier (2026), they need a CDC Dog Import Form receipt, must be at least 4 months old, must appear healthy on arrival, and must have a microchip that a universal scanner can read.

The CDC is the main authority for dogs entering or returning to the United States (USDA APHIS, 2026). CDC rules depend on where the dog was vaccinated and whether it has been in a country at high risk for dog rabies in the past 6 months (CDC, "Bringing a Dog into the U.S.," 2024). USDA APHIS says dogs vaccinated in the U.S. that have been to a high-risk country in the past 6 months need a "Certification of U.S.-Issued Rabies Vaccination" form, completed by a USDA-accredited veterinarian before the dog leaves the U.S.

Frontier pet rules vs. Animal Passport: two different things

Searches for "pet passport" and "airline pet policy" often get mixed up, so here is the difference plainly.

• Frontier's pet policy is an airline's contract rules. Official travel documents come from government schemes: the DOT service animal form, CDC dog import requirements, USDA-endorsed health certificates and state or territory entry rules.
• Animal Passport is a digital animal and livestock identity record built on muzzle biometrics. An animal's nose print is unique, like a fingerprint. A phone captures it, and the record links the owner, breed, estimated age, body condition and vaccination history. Age is estimated from a dental photograph with a confidence score, and body condition is scored 1 to 5 from a side-profile photo.

Animal Passport is not a government-issued travel document. It does not replace the DOT form, a CDC import receipt or a veterinary health certificate, and Frontier does not ask for it. It was built mainly for livestock identity. In the Pakistan floods of August 2025, it was used in livestock rescue so farmers could reclaim animals after paper ear tags washed away. That is a problem airline pet rules don't address. You can read more on the Animal Passport blog.

Bottom line: for a Frontier flight, follow Frontier's pet or service animal rules and any government entry requirements. A biometric ID record, from Animal Passport or anyone else, is not a boarding document.

Practical checklist before you fly Frontier with a pet

1. Re-check the fee and rules on Frontier's official pages within a week of departure.
2. Measure the carrier, including the height, which is the dimension most likely to fail.
3. Add the pet to your booking so you don't have to pay at check-in.
4. Confirm health certificate rules for your destination state or territory.
5. For service dogs, submit a typed DOT form at least 48 hours ahead and keep a copy.
6. Choose a seat that is not in row one or an exit row.
7. Follow Frontier's guidance on food and water before departure, and talk to your veterinarian about travel stress.