Pets on Flights With United Airlines: 2026 Rules, Fees and Carrier Sizes

Pets on flights with United Airlines means cats and dogs traveling in the cabin in a carrier that fits fully under the seat in front of you. As of October 2026, United charges $150 each way per pet, sets no weight or breed limit, and allows hard-sided carriers up to 17.5 x 12 x 9 inches or soft-sided carriers up to 18 x 11 x 11 inches. Pet cargo (PetSafe) is closed to the general public, so a dog too large for an under-seat carrier cannot fly with United as a pet.

This guide is written by the Animal Passport editorial team and was last updated on October 1, 2026. It sets out United's current cabin pet rules, the government paperwork that applies on top of them, and where sources disagree. We cross-checked United's figures against several independent 2026 guides that quote United's published policy, and the government requirements come directly from the Centers for Disease Control and Prevention (CDC), the United States Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) and the International Air Transport Association (IATA). Airline rules can change without notice, so confirm your itinerary on united.com before you book.

United Airlines pet policy at a glance (October 2026)

Which pets can fly in the cabin on United?

United allows only cats and dogs in the cabin, according to Borderless Moves (2026), which quotes United's own pages. Rabbits, birds and other companion animals are not accepted as cabin pets. Borderless Moves also reports that United publishes no weight or breed limit for cabin pets. That contradicts the "20 lb limit" still repeated in some older articles.

Flat-faced (brachycephalic) breeds such as pugs, French bulldogs and Persian cats can fly in the cabin if they fit the carrier. Explore With Lora (2026), written by an owner who flies regularly with a pug, describes United's cabin-only model as workable for snub-nosed dogs because those breeds never go in the hold.

Age minimums: where sources disagree

For domestic flights, the guides agree that pets must be at least 8 weeks (2 months) old. For international travel they disagree. Canine Cab (2026) gives a single 16-week minimum, while Borderless Moves (2026) reports 6 months for dogs and 4 months for kittens. For dogs flying into the United States, the federal rule takes priority over either figure: the CDC requires every imported dog to be at least 6 months old at entry (CDC, effective August 1, 2024).

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

United charges $150 each way per pet for cabin travel. A round trip with one dog therefore costs $300 in pet fees on top of your ticket, according to Explore With Lora (verified September 13, 2026) and Borderless Moves (2026). Older figures such as $125 still turn up online, even inside some 2026 articles, so treat any lower number as out of date unless United's own page shows it.

Expect costs beyond the airline fee. Canine Cab (2026) estimates $40 to $90 for an airline-compliant soft carrier and $60 to $250 for a veterinary visit and health certificate, depending on whether a USDA endorsement is needed. These are editorial estimates, not official prices.

What size carrier does United allow?

• Hard-sided carrier: maximum 17.5 x 12 x 9 inches (44 x 30 x 22 cm).
• Soft-sided carrier: maximum 18 x 11 x 11 inches (45 x 27 x 27 cm).
• The carrier must be ventilated, fit fully under the seat in front of you with the door closed, and stay there for the whole flight.
• Your pet must be able to stand up and turn around inside it. The gate agent makes the final call.

Most cabin travelers choose soft-sided carriers because they compress slightly to fit under-seat spaces that vary by aircraft. For sizing the carrier to the animal, IATA publishes the industry's Live Animals Regulations (LAR) and separate Operational Guidelines for In-Cabin Pet Transport. The current LAR edition took effect on January 1, 2026 (IATA, 2026).

Seats and aircraft where pets are not allowed

Borderless Moves (2026) reports that pets are not allowed in emergency exit rows, in United Premium Plus, or in the front row of any cabin. It also reports that the usual two-pets-with-two-seats allowance drops to one pet per person on some narrow-body aircraft, including the A319, A320, A321neo, 737-800/MAX 8 and 737-900/MAX 9. Seat-map rules change often, so check yours when you book.

Is United PetSafe cargo still available?

No, not for the general public. Borderless Moves (2026) quotes United's current page as saying, "We no longer let you check your pets through the PetSafe program." The remaining cargo exemption covers active-duty U.S. military on Permanent Change of Station (PCS) orders and U.S. State Department Foreign Service staff, and, according to the same source, their spouses. Canine Cab (2026) dates the suspension to 2018.

If your dog is too big for an under-seat carrier, United is not an option. Your realistic choices are a professional pet shipper that books cargo on another carrier under IATA Live Animals Regulations, or ground transport.

How to book a pet on a United flight: step by step

1. Check the route. Make sure your origin, destination and any connection are not on United's restricted list (see below).
2. Measure your pet and carrier. Confirm the carrier is within the hard-sided or soft-sided limits and that your pet can stand and turn around inside it.
3. Add the pet to your reservation. Explore With Lora (September 2026) reports you can choose "Travel with a pet" on united.com or add it later in My Trips for domestic flights, but not in the mobile app, and that international trips need a phone call. Canine Cab (2026) instead advises booking by phone at 1-800-864-8331 at least 24 hours before departure. When in doubt, call.
4. Pay the $150 fee. Cabin pet spaces are limited per flight and offered first come, first served, so book early.
5. Arrange the paperwork. Get any health certificate, rabies record, CDC Dog Import Form or destination permit your route needs.
6. Check in with an agent. Explore With Lora (2026) notes that you cannot check in online when traveling with a pet, so allow extra time at the airport.

Where United does not allow pets

Borderless Moves (2026) lists destinations where United does not carry pets to, from or through, including Australia, Hawaii, New Zealand, the United Kingdom, Ireland, Iceland, Hong Kong, Brazil, South Africa, Spain, Sweden, Taiwan, Thailand, the Philippines and the United Arab Emirates (Dubai), among others. Some of these restrictions may apply only to certain routes. Canine Cab (2026) gives a shorter list (Hawaii, Australia, New Zealand, the UK and Ireland). Because the two sources differ, confirm your exact itinerary with United.

Paperwork for flying a pet internationally on United

United's cabin rules are only part of what you need. Government rules apply separately, and they are usually the harder part.

Dogs entering or returning to the United States (CDC)

The Centers for Disease Control and Prevention (CDC) is the main authority for dog imports, as USDA APHIS states on its pet travel page (last modified March 20, 2026). Since August 1, 2024, a dog that has been only in dog-rabies-free or low-risk countries for the previous 6 months needs:

• A CDC Dog Import Form receipt, which is free, valid for 6 months and required for each dog.
• A microchip that a universal scanner can read.
• A minimum age of 6 months at entry, and the dog must appear healthy on arrival.

Dogs that have been in a high-risk country for dog rabies have additional requirements, and the CDC will not admit an unvaccinated dog from a high-risk country (CDC, 2024). USDA APHIS (2026) adds that U.S.-vaccinated dogs returning from a high-risk country need a "Certification of U.S.-Issued Rabies Vaccination" form, submitted by a USDA-accredited veterinarian before the dog leaves the United States.

Pets leaving the United States (USDA APHIS)

USDA APHIS (2026) advises contacting a USDA-accredited veterinarian as soon as you decide to travel. The veterinarian can tell you the destination country's entry requirements and help you get a USDA-endorsed pet health certificate. APHIS also notes that animals classed as livestock or poultry, such as pigs or chickens, do not qualify for pet travel and come under separate import and export rules.

Service animals and emotional support animals on United

Explore With Lora (2026) reports that emotional support animals fly as ordinary pets on United. They pay the $150 fee and must follow the carrier rules. Trained service dogs are exempt from the fee and the carrier requirement. For flights to or from the U.S., the service dog must be added to the reservation in advance along with the U.S. Department of Transportation (DOT) Service Animal Air Transportation Form. Up to two service dogs may fly free if they meet United's requirements.

Pet travel documents vs. Animal Passport: not the same thing

The word "passport" causes real confusion in pet travel, so here is the distinction.

• Official pet travel documents include the CDC Dog Import Form, USDA-endorsed health certificates, rabies certificates and schemes such as the EU pet passport. Governments set these requirements, and your airline and destination country check them.
• Animal Passport is a digital animal and livestock identity record built on muzzle biometrics: an animal's nose print is unique, much like a human fingerprint. A phone camera captures the print, and the record links the owner, breed, estimated age (from a dental photograph, with a confidence score), a 1 to 5 body condition score (from a side-profile photo) and vaccination history.

Animal Passport is not a United Airlines booking, a veterinary health certificate, a CDC form or a government-issued travel document. It does not replace any document listed in this guide. Its main use is proving who owns an animal. In August 2025, livestock farmers in Pakistan used it during flood rescue work to reclaim animals after their paper tags washed away. You can read more about biometric animal identity on the Animal Passport blog.

Practical checklist before your United pet flight

• Route checked against United's restricted destinations, including any connection.
• Carrier within 17.5 x 12 x 9 in (hard) or 18 x 11 x 11 in (soft) and ventilated.
• Pet booked and paid for, with a confirmation, not just a payment receipt.
• CDC Dog Import Form receipt, microchip and age of 6 months or more for dogs entering the U.S.
• USDA-endorsed health certificate and destination permits for outbound international trips.
• Original paperwork in your hand luggage, and extra time for agent check-in.

For more guides on flying with animals and on animal identity, browse the Animal Passport blog.