Southwest Airlines Pet Policy for Dogs and Cats

Southwest takes a small cat or dog in the cabin, under the seat in front of you, and nowhere else on the aircraft. Its pet policy page, read September 24, 2026, says “No pets are transported in the cargo compartment,” so a pet that does not fit under a seat travels with another airline or by road.

The fee is set by the carrier rather than by the animal. Southwest’s Optional Travel Charges page, read the same day, prices it one way per pet carrier: $125 on the US mainland and $35 between the Hawaiian Islands.

Southwest’s pet policy page, read September 24, 2026, accepts cats and dogs at least eight weeks old, in the cabin on domestic flights. It calls them “small, vaccinated domestic cats and dogs” and does not list the vaccinations it means, so ask Southwest when you reserve if your pet’s record is short. Unaccompanied minors cannot travel with a pet.

Space is limited, and Southwest recommends reserving the pet’s place in advance by calling.

Southwest’s Optional Travel Charges page, read September 24, 2026, prices a pet one way per pet carrier: $125 on the US mainland and $35 between the Hawaiian Islands. The same page says Southwest may amend the prices it lists at any time.

The pet policy page adds how the charge is paid. The Pet Fare is paid at the Southwest ticket counter with an accepted credit card, and it is refundable if you cancel the reservation. It also says, “Pet Fare pricing is subject to change at any time.” Pets earn no Rapid Rewards points, according to Southwest’s additional pet information article.

The fee is priced per pet carrier. Southwest’s pet policy page also lets one carrier hold up to two small cats or dogs of the same species, so when you call to reserve, confirm how it prices two animals sharing one.

Southwest’s pet carrier article, read September 24, 2026, sets two limits, each given as length by width by height:

Whichever you use, it has to fit under the seat in front of you, be designed as a pet carrier, and be leak-proof and well ventilated. Your pet, head and tail included, has to be completely inside and able to stand up and move around with ease.

Southwest recommends a soft-sided carrier, because under-seat space varies with the type of seat and where it sits on the aircraft. It names aisle seats among the places where that space can be tighter. Measure the carrier as well as the pet, and check it against the airline’s published limit before the trip. Our pet carrier size checker sets IATA’s minimum inside dimensions for your dog or cat beside the under-seat limits US and Canadian airlines publish.

The Optional Travel Charges page also lists a pet carrier among the items for purchase at the ticket counter, at $58. Buying one on travel day is a fallback, since it is a carrier your pet has never been inside.

Yes, it takes the place of one of your two items. Southwest’s carrier article says you may board with the pet and a personal item, or with the pet and a regular size carry-on bag, and each ticketed customer may bring one pet carrier.

Under the seat in front of you, inside its carrier, for the whole flight. Southwest’s onboard article, read September 24, 2026, says a pet must never occupy a passenger seat and may not be in an exit row or in the first row, the bulkhead. The pet stays in the carrier, head and tail included, in the gate area, during boarding and deplaning, and for the entire flight.

Not to or from Hawaii, and not abroad. Southwest’s destination article, read September 24, 2026, says pets are not allowed on flights to or from Hawaii and are accepted between the Hawaiian Islands. It also says, “Pets are not allowed on international flights or any itinerary that includes an international flight.” So a domestic Southwest leg booked together with an overseas trip is ruled out too.

A move from the mainland to Hawaii therefore flies with another carrier, and the state’s own entry rules apply whichever one it is. Our guide to relocating to Hawaii with pets covers the state’s requirements. For Puerto Rico, the destination article says only that specific requirements may apply, so ask Southwest before you book.

None of the six Southwest pet articles read on September 24, 2026 names a breed it refuses. Its additional pet information article says animals with heart disease, anxiety disorders or brachycephalic airways are more susceptible to complications during flight, and adds, “You and your vet are best suited to determine if your pet can travel safely.” For a snub-nosed dog or cat, that conversation with your veterinarian comes before the booking.

Southwest’s pet policy and pet carrier articles, read September 24, 2026, give no weight limit, for the animal alone or with its carrier. What they limit is the carrier’s size and the room inside it, so a dog near the line is decided by the tape measure, and the word “small” in the policy.

Southwest’s airport article, read September 24, 2026, sets out the day. You pay the Pet Fare at the ticket counter. At the security checkpoint you hold your pet and walk through the screening device while the carrier is X-rayed, and it may be searched. Boarding is with your assigned group.

Pet relief areas are available at each location Southwest serves, and it says it will not hold a flight while you take your pet to one. A pet stroller travels at the standard checked bag fees, and the airline does not assume liability for damage to it.

A pet that behaves disruptively may be denied boarding. Southwest’s examples include scratching, excessive whining or barking, growling, biting, jumping, lunging, and urinating or defecating in the cabin or gate area.

No Southwest fare changes the answer, because the cabin is the only place it carries a pet. What remains is another airline’s hold or cargo service, or a move by road. American Airlines Cargo carries pets for the general public through its PetEmbark service. Our American Airlines pet policy guide covers its terms, and our post on flying with a large dog sets out the other routes and the order to try them in.

Within the continental US, road relocation from one state to another is one of the services we arrange, and it can be booked on its own. JetBlue also carries pets in the cabin only. Our JetBlue pet policy guide covers its limits. Our guide to US airline pet policies compares the larger US carriers.

When Southwest fits, the work is in the details above: a carrier within 18 by 10.5 by 10 inches with room for the pet to move, an itinerary with no international flight anywhere in it, and the pet’s place reserved by phone early.

Each part of a move can be taken on its own: the flights, the check-in with the airline, the paperwork your destination asks for, door-to-door relocation with a partner driver, and meeting your pet at the arrival airport. Take the whole move, or only the pieces you need. Pet Travel Advisors was founded in 2023, and our team holds IATA Live Animals Regulations certificates. Request a quote with your route and dates.

Every rule and figure here comes from Southwest’s own pages, each read on September 24, 2026:

Southwest says its Pet Fare pricing can change at any time, so confirm the charge and the carrier limit with Southwest when you reserve.