Southwest Airlines Pet Policy for Dogs
Flying with a small dog on Southwest? Here are the current 2026 fees, carrier rules, booking steps, and key restrictions to know before you travel.
Southwest Airlines Pet Policy Overview
Southwest allows small vaccinated domestic dogs to travel in the cabin on domestic flights when they stay inside an approved carrier under the seat. Pets are accepted on a first-come, first-served basis and are not transported in cargo.
Southwest accepts small vaccinated domestic cats and dogs in the cabin on flights within the United States. Pets must remain in a leak-proof, well-ventilated carrier at all times in the gate area, during boarding and deplaning, and onboard. Unaccompanied minors may not travel with a pet, and passengers with pets may not sit in an exit row or any seat without under-seat stowage. Southwest does not accept pets on international flights and does not transport pets in cargo.
Last updated: 2026-03-25
How to Book Your Dog on Southwest Airlines
Confirm your dog qualifies. Southwest only accepts small vaccinated domestic dogs that are at least 8 weeks old and can stay comfortably inside a leak-proof, ventilated carrier under the seat.
Book your own flight first. Because Southwest limits pet carriers to six per flight, choose your itinerary early if you plan to bring your dog.
Add the pet reservation as early as possible. Southwest states pet space is first-come, first-served, so contact Southwest promptly after booking to confirm availability for your specific flight.
Use an airline-compliant carrier. Your dog must be able to stand and move around with ease inside the carrier, and the carrier must fit under the seat in front of you for the entire flight.
Arrive early at the airport. Southwest notes that pet travel is handled by Southwest personnel at the airport, so plan extra time to check in and pay any applicable pet fee if it has not already been collected.
Keep your dog inside the carrier at all times in the terminal and onboard. Southwest requires the pet to remain fully inside the carrier, including head and tail, in the gate area, during boarding and deplaning, and throughout the flight.
Choose an eligible seat. You cannot sit in an exit row or in a seat with no forward under-seat stowage when traveling with a pet.
Bring vaccination and destination paperwork if needed. Southwest requires pets to be vaccinated, and you are responsible for any destination-specific health or entry requirements.
Know the limits. Only one pet carrier is allowed per passenger, and up to two dogs of the same species may share one carrier if they fit safely and comfortably.
Have a backup plan for sold-out pet capacity. Since pet spots are capped per flight, a later flight or different itinerary may be necessary if the pet allotment is already full.
Southwest Airlines vs Other Airlines
| Feature | Southwest Airlines | American Airlines | Delta Air Lines |
|---|---|---|---|
| In-Cabin Fee | $125 one-way per carrier (U.S. Mainland); $35 between Hawaiian Islands | $150 per kennel each way | $150 each way for U.S./Canada/Puerto Rico/U.S. Virgin Islands tickets issued on/after April 8, 2025 |
| Cargo Fee | Not offered | Varies via American PetEmbark cargo; checked pets only for active-duty U.S. military and State Department personnel on official orders ($200 per kennel in many regions) | Not listed on the main pet overview page for standard pet cargo; in-cabin policy emphasized |
| Weight Limit | No published pet+carrier weight limit; dog must fit comfortably in carrier | Checked pets: max 100 lbs combined pet and kennel; no published carry-on combined weight limit | No published pet+carrier combined weight limit; pet must fit comfortably in kennel |
| Carrier Size | Must fit under seat; Southwest sells a pet carrier at the airport for $58 | Soft-sided recommended: 18 x 11 x 11 in | Recommended soft-sided kennel: 18 x 11 x 11 in |
| Breeds Restricted | No breed list published for in-cabin pets; aggressive or incompatible pets may be refused | Breed and destination restrictions apply; larger pets may need cargo | Restrictions vary by destination and aircraft; pet must remain in kennel and fit under seat |
| Booking Method | Reserve early; limited to 6 pet carriers per flight; handled by Southwest personnel at the airport | Add carry-on pet in aa.com or app, then pay and verify at airport | Call Delta Reservations as soon as possible with kennel dimensions |
Frequently Asked Questions
Does Southwest allow dogs in the cabin?
Yes. Southwest accepts small vaccinated domestic dogs in the cabin on flights within the United States when they travel in an approved carrier under the seat.
How much does Southwest charge for a dog?
Southwest charges $125 one-way per pet carrier on U.S. Mainland itineraries and $35 one-way between Hawaiian Islands.
Can my dog fly in cargo on Southwest?
No. Southwest does not transport pets in the aircraft cargo compartment.
Is there a weight limit for dogs on Southwest?
Southwest does not publish a combined pet-and-carrier weight limit on its pet policy materials. Instead, your dog must be small enough to stand up and move around comfortably inside the carrier, and the carrier must fit under the seat.
How many dogs can travel in one carrier on Southwest?
Up to two animals of the same species may travel in one carrier, provided they fit safely and comfortably.
Do I need to book my dog's spot in advance on Southwest?
Yes, you should arrange pet travel as early as possible. Southwest limits pet carriers to six per flight and accepts them on a first-come, first-served basis.
Can I sit anywhere on the plane with my dog?
No. Passengers traveling with pets may not sit in an exit row or in a seat with no forward under-seat stowage.
Can an unaccompanied minor bring a dog on Southwest?
No. Southwest states that unaccompanied minors may not travel with a pet.