Does Frontier Airlines Allow Pets? What the 2026 Rules Actually Say

Yes. Frontier Airlines allows pets, but only in the cabin and only on flights within the United States. As of October 2026, Frontier accepts domesticated dogs, cats, rabbits, guinea pigs, hamsters and small household birds in an under-seat carrier for a non-refundable $149 per pet, each way, according to Frontier Airlines' Optional Services page. Frontier does not fly pets in cargo or as checked baggage, and it no longer accepts new pets on international flights.

The Frontier Airlines pet policy is the set of published rules the Denver-based ultra-low-cost carrier uses to decide which animals may board, how they must be contained, and what they cost. This guide answers the yes-or-no question first, then covers the conditions that decide whether your animal qualifies. Every rule below comes from Frontier's own pages or from U.S. government sources opened on October 5, 2026.

If you want the full Frontier fee and service-dog paperwork breakdown, see our companion guide, Frontier Airlines Policies: Pets, Service Dogs and Fees 2026.

The short answer: yes, if five conditions are met

Frontier says yes to pets in principle, but your animal has to clear every one of these tests, according to Frontier Airlines' pet FAQ and Family & Pets page (2026):

1. Domestic route. The flight must be within the United States. Frontier states it "will not accept new pets for International Travel."
2. Approved species. Domesticated dog, cat, rabbit, guinea pig, hamster or small household bird.
3. Minimum age. Dogs and cats must be at least 8 weeks old.
4. Under-seat fit. The carrier must fit under the seat in front of you and let the pet stand, turn around and lie down naturally.
5. One pet per passenger. Each passenger may bring one pet in the cabin, and only one adult dog or cat per container.

If any one of these fails, the answer becomes no, because Frontier has no cargo or checked-pet option to fall back on.

Which pets does Frontier allow, and which are banned?

Frontier Airlines publishes both an allowed list and a "never accepted" list on its Family & Pets page. The never-accepted list is unusually specific, and it includes some animals that people commonly keep as pets.

Note the quirk: hamsters and guinea pigs are allowed, while mice and rats are banned as rodents. Check the exact species against Frontier's list rather than assuming a similar animal qualifies.

How much does Frontier charge to fly with a pet?

Frontier Airlines lists a "Pet Charge: $149 per pet, per direction (Non-Refundable)" on its Optional Services page as of October 2026. A round trip with one pet therefore costs $298 in pet fees before seats or bags.

According to Frontier's Family & Pets page, the charge may be paid during booking; if you do not prepay, you pay when you check in your pet. The pet carrier does not replace your bag allowance. You may still bring either one personal item (8 x 14 x 18 in.) or one carry-on bag (10 x 16 x 24 in.), and the carry-on has its own fee.

Because the pet charge is non-refundable, confirm your carrier size and destination paperwork before you pay, not at the gate.

What size pet carrier does Frontier allow?

Frontier Airlines sets the maximum hard-sided container at 18 in. long x 14 in. wide x 8 in. high and the maximum soft-sided container at 18 in. x 14 in. x 11 in., according to its pet FAQ (2026). Frontier recommends soft-sided carriers.

The extra 3 inches of height for soft-sided bags matters, because soft sides can compress to fit under the seat. Frontier also warns on its Family & Pets page that some seats cannot accommodate a pet container and says it will work with you to find a seat with space. You may not sit in row one or an exit row with a pet.

Practical sizing rule

Frontier publishes no weight limit for pets. The real limit is the carrier: if your pet cannot stand, turn around and lie down naturally inside an 18 x 14 x 11 in. soft carrier, it is too large to fly Frontier as a pet.

How to add a pet to a Frontier booking

Frontier Airlines' pet FAQ (2026) describes two online routes. You do not need to call.

1. Book your flight on a route within the United States.
2. During booking, select Cabin Pet in the Passenger Info section.
3. If you already booked, open Manage Trip and choose Add Pet in Cabin.
4. Pay the $149 one-way charge, or pay it at pet check-in.
5. Choose a seat that is not in row one or an exit row.
6. Check your destination state's animal entry rules (see the health certificate section below).
7. On the day, keep the pet in its carrier for the entire trip, including on board.

Does Frontier allow pets in cargo or as checked baggage?

No. Frontier Airlines' pet FAQ states that pets "travel in the cabin with you" and that "we do not transport pets in the cargo hold." Its Family & Pets page adds: "We do not allow pets to be checked as baggage."

This is the most important limit for owners of medium and large dogs. Unless the dog is a trained service dog, a dog too big for an under-seat carrier cannot travel on Frontier at all. Owners in that position need a different airline that offers checked or cargo pet transport, confirmed on that airline's official policy page, or ground transport.

Can you fly internationally with a pet on Frontier?

No, not with a pet. Frontier Airlines' Family & Pets page states that Frontier "will not accept new pets for International Travel" and will only accept service animals internationally under specific requirements.

For international service dogs, Frontier requires a Centers for Disease Control and Prevention (CDC) Dog Import Form receipt, proof of a microchip readable by a universal scanner, and a dog that appears healthy on arrival. Dogs from countries the CDC classes as high-risk for dog rabies need extra documentation. The CDC says its requirements depend on where the dog was vaccinated and which countries it has been in during the 6 months before entering the U.S.

Frontier's own pages disagree on minimum age

As of October 2026, Frontier's Family & Pets page says international service dogs must be "at least 4 months old," while its Special Services page says "at least 6 months old." We could not find an official explanation for the difference. If your service dog is between 4 and 6 months old, confirm with Frontier in writing before booking an international trip.

Does Frontier allow emotional support animals?

Only as pets. Frontier Airlines' Special Services page says that as of February 1, 2021, Frontier "will no longer accept emotional support animals onboard" and that the animal "may be eligible to travel in accordance with our Pet Policy for a fee."

That policy is permitted by federal law. The U.S. Department of Transportation (DOT) final rule on traveling by air with service animals, published in the Federal Register on December 10, 2020, states that carriers "are not required to recognize emotional support animals as service animals and may treat them as pets." The same rule defines a service animal as a dog individually trained to do work or perform tasks for a qualified person with a disability.

In practice, an emotional support cat or small dog can still fly Frontier if it meets every pet rule: approved species, carrier size, domestic route and the $149 fee.

Trained service dogs

Trained service dogs follow separate rules. Frontier's Special Services page says it accepts only dogs, including fully trained psychiatric service dogs, limits each passenger to two service animals, and requires the DOT Service Animal Air Transportation Form at least 48 hours before travel for reservations booked earlier than that. A passenger with a trained service dog may also bring one pet in the cabin, according to Frontier's pet FAQ.

Do you need a health certificate for a pet on Frontier?

Frontier does not require one for domestic cabin pets, but your destination might. Frontier's Family & Pets page says it does "not require a health certificate for pets carried in the cabin traveling within the U.S.," while noting the state you land in may require one.

The United States Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) confirms the split in responsibility. On its interstate pet travel page, last modified June 10, 2026, APHIS states that it "doesn't regulate the interstate movement of pets by their owners" and that "domestic movement requirements are set by the receiving State or Territory." APHIS links to each state's requirements and recommends contacting your veterinarian as soon as you know your travel details.

U.S. territories are stricter. For Puerto Rico, Frontier lists an official health certificate valid for 30 days, rabies vaccination within six months for pets over four months old, external parasite treatment within 72 hours of entry, and official identification by microchip or metal ID tag.

Why some websites give different Frontier pet rules

Sources disagree, and the differences change your plans. A third-party guide on The Nomad Paws, last updated February 13, 2026, lists a $99 fee, an 18 x 14 x 8 in. maximum for all carriers, and phone-only pet booking. Frontier's own pages, checked on October 5, 2026, show:

• Fee: $149 per pet, per direction (Frontier Optional Services page), not $99.
• Soft-sided carrier: up to 11 in. high (Frontier pet FAQ); the 8 in. limit applies only to hard-sided carriers.
• Booking: online, via Cabin Pet during booking or Add Pet in Cabin in Manage Trip (Frontier pet FAQ).

When a blog and the airline disagree, the airline's current page controls. Airline fees change often, so recheck Frontier's Optional Services page on the day you book.

Frontier in-cabin rules your pet must follow

Frontier Airlines' Family & Pets page (2026) sets these onboard conditions:

• Your pet must remain in its travel container at all times.
• Your pet must be "harmless, not disruptive, odorless, and require no attention during flight."
• Frontier asks that you not give food or water on board and recommends no food or water within four hours of departure.
• No oxygen will be given to a pet in an emergency.
• Frontier notes that most veterinarians advise against sedating pets for flights because tranquilizer effects at altitude are unpredictable. Ask your own veterinarian before giving any medication.

Frontier pet rules vs. Animal Passport biometric ID

Frontier's pet policy, DOT service animal forms, CDC dog import receipts and state health certificates are official airline and government requirements. Animal Passport is a different kind of product, and the two should not be confused.

Animal Passport is a digital animal and livestock passport that identifies an animal by muzzle biometrics; a nose print is unique, like a fingerprint. Using a phone, it builds a record that binds the owner, breed, estimated age, body condition and vaccination history. It estimates age from a dental photograph with a confidence score and gives a body condition score from 1 to 5 from a side-profile photo. In August 2025 it was used in livestock flood rescue in Pakistan so farmers could reclaim animals after paper tags washed away.

Animal Passport is not an airline pet booking, not a DOT form, not a health certificate and not a government-issued travel document. It does not provide veterinary diagnosis or legal advice. For a Frontier flight, use only the official documents described above. You can read more about animal identification and travel rules on the Animal Passport blog.

Quick decision checklist

1. Is the flight entirely within the United States? If not, only a trained service dog can come.
2. Is the animal a dog, cat, rabbit, guinea pig, hamster or small household bird?
3. Is a dog or cat at least 8 weeks old?
4. Does it fit comfortably in a carrier no larger than 18 x 14 x 11 in. (soft) or 18 x 14 x 8 in. (hard)?
5. Have you budgeted $149 each way, plus any carry-on fee?
6. Have you checked your destination state's or territory's entry rules through USDA APHIS?

If you answered yes to all six, Frontier will allow your pet. If not, Frontier is the wrong airline for this trip.

By Animal Passport. Last updated October 5, 2026. Rules are summarized from official Frontier Airlines, U.S. Department of Transportation, CDC and USDA APHIS pages opened on that date. Airline policies change; always confirm on Frontier's official pages before booking.