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Southwest Airlines Pet Policy 2026: $95 Fee, No International Routes, and Full Cabin Rules

Anano Gudushauri
July 16, 2026
10 min read
Southwest Airlines Pet Policy 2026

Southwest Airlines allows you to bring your small dog or cat on board for just $95 each way, making it the most affordable major airline in the United States for in-cabin pet travel. When compared directly to the $150 fees charged by competitors like Delta Air Lines and United Airlines, Southwest saves you a guaranteed $110 on every round-trip journey. However, there is a major structural trade-off for this lower price: Southwest completely bans pets from flying on any of its international routes, meaning you cannot use this carrier to travel with your pet to destinations in the Caribbean, Central America, or Mexico.

Southwest Airlines Pet Policy Quick Summary

  • In-Cabin Pet Fee: $95 USD each way per pet carrier. The fee is non-refundable but can be reassigned to a future flight if you cancel.

  • Permitted Species: Small vaccination-certified domestic dogs and cats only.

  • Weight Limits: No official weight limit for the pet, but they must fit comfortably inside an approved under-seat carrier.

  • Carrier Dimensions: Recommended soft-sided carrier size is 18.5” L x 13.5” W x 8.5” H (46.9 cm x 34.2 cm x 21.5 cm).

  • Cargo & Checked Baggage: Southwest does not offer cargo or checked baggage transport for animals under any circumstances. All pets must travel in the cabin.

  • Hawaii Route Restrictions: Pets are strictly prohibited on flights to, from, or connecting through Hawaii due to state quarantine laws.

Deep Dive: In-Cabin Pet Rules (PETC)

Southwest Airlines welcome cats and dogs inside the passenger cabin on all domestic flights, excluding routes to or from Hawaii. The airline enforces a hard limit of six pet carriers per scheduled flight. Because these spots are distributed on a strict first-come, first-served basis, registering your pet as early as possible is critical to securing your travel plans.

Your dog or cat must be at least 10 weeks old to board a Southwest flight. They must remain completely inside their fully zipped, leak-proof, and ventilated carrier for the entire duration of the trip, including during boarding, the flight itself, and while deplaning. Under-seat space is precious, and Southwest agents are trained to verify that your pet has enough space to stand up, turn around, and lie down naturally inside their carrier at check-in.

The physical dimensions of the under-seat space vary slightly depending on the specific aircraft frame you fly:

  • Boeing 737-700: Under-seat clearance is slightly taller, allowing for a standard soft-sided carrier.

  • Boeing 737-800 and 737 MAX 8: These newer planes have slightly lower under-seat clearances, which is why a flexible, soft-sided carrier is highly recommended.

The maximum allowable dimensions for a soft-sided carrier are 18.5" L x 13.5" W x 8.5" H. If you choose to use a hard-sided carrier, the maximum dimensions are strictly capped at 13.5" L x 8.5" W x 8.5" H. Because soft-sided carriers can compress slightly to conform to different aircraft floor structures, they are highly preferred.

Your pet carrier counts directly as your single carry-on personal item. When traveling with a pet, you are still permitted to bring one regular carry-on suitcase to store in the overhead bin, but you cannot bring an additional laptop bag, backpack, or purse. The pet carrier must take the place of your small personal item under the seat in front of you.

Only one pet carrier is allowed per ticketed passenger. However, Southwest does allow you to place up to two small dogs or two small cats of the same species inside a single carrier, provided they can both stand up and move around without restriction. If you place two animals in one carrier, you still pay only the single $95 fee each way.

Cargo and Checked Hold Pet Rules

Southwest Airlines does not operate a cargo department for live animal shipments, nor do they allow pets to travel as checked baggage in the hold. If you have a medium, large, or extra-large dog, they cannot travel with you on Southwest.

+-------------------------------------------------------------------------+
|                    THE SOUTHWEST HOLST-ONLY BAN                         |
|                                                                         |
| Southwest has engineered its entire operational model around fast       |
| gate turnarounds. Because of this, they do not have the specialized     |
| temperature-controlled cargo systems required to transport live animals |
| safely in the aircraft belly. All pets must fit under the cabin seat.   |
+-------------------------------------------------------------------------+

This absolute cabin-only policy protects animals from tarmac heat risks and cargo compartment pressure fluctuations, but it limits Southwest pet travel exclusively to small animals. If your pet and carrier do not meet the under-seat dimension rules, you will need to book with a carrier that operates a dedicated, climate-controlled cargo pet network.

Breed Restrictions

For in-cabin travel, Southwest Airlines does not enforce any breed-specific bans or restrictions. You can fly with flat-faced (brachycephalic) dogs and cats, such as Boston Terriers, French Bulldogs, Pugs, or Persian cats, without regulatory obstacles.

However, traveling with a brachycephalic pet requires a high level of personal vigilance. Because short-nosed animals have compressed upper airways, they are highly susceptible to respiratory distress when stressed, hot, or confined in small spaces.

When flying with a brachycephalic breed on Southwest, you must prioritize airflow:

  1. Choose a mesh-heavy carrier: Ensure your soft-sided carrier features durable mesh ventilation panels on at least three, and preferably four, sides to keep air circulating under the seat.

  2. Monitor cabin temperatures: If you notice the cabin warming up while sitting on the tarmac, adjust your overhead air nozzle to point directly down toward your pet's carrier.

  3. Use calming strategies: Acclimate your pet to their carrier weeks before the flight to keep their heart and respiratory rates low during the journey.

International Route Requirements and Hawaii Restrictions

Southwest Airlines operates flights to a variety of international destinations across Central America, Mexico, and the Caribbean. However, the airline maintains a strict, zero-exceptions ban on international pet travel. If your flight path crosses a United States border, your pet is not permitted to board, even if they meet all in-cabin size and weight parameters.

Furthermore, Southwest does not allow pets on flights to, from, or connecting through the state of Hawaii.

+-------------------------------------------------------------------------+
|                     THE HAWAIIAN QUARANTINE BARRIER                     |
|                                                                         |
| Hawaii is rabies-free and enforces exceptionally strict agricultural     |
| laws, including mandatory multi-day quarantine protocols for arriving    |
| animals. Because Southwest’s rapid, point-to-point operational system is|
| not designed to manage state veterinary inspections, the airline completely|
| bans pets on all flights routing to or from the islands.                 |
+-------------------------------------------------------------------------+

If you plan to travel internationally or to Hawaii with your dog or cat, you must coordinate your trip with a carrier that accepts pets on these specific routes and meets local entry documentation demands. Pet Holiday Club covers 190+ countries with government-sourced, vet-verified pet travel checklists at petholidayclub.com, helping you map out exactly which documentation, blood titers, and import permits are required for foreign destinations before you book.

How to Book a Pet on Southwest Airlines

Because Southwest limits the number of pets allowed in the cabin on each flight to six, you should add your pet to your reservation immediately after booking your passenger ticket.

1.Check Route Eligibility: Before Booking.

Ensure your desired itinerary is entirely domestic and does not include any stops or final destinations in Hawaii or international territories.

2.Add Pet to Your Booking: At Checkout.

While purchasing your ticket on Southwest Airlines official website, look for the "Special Assistance" link under the passenger details section. Click "Travel with a Pet" to request a spot for your dog or cat.

3.Call Customer Service: Alternative Option.

If you have already booked your flight, or if you prefer to confirm space availability before purchasing your ticket, call Southwest Customer Support at 1-800-I-FLY-SWA (1-800-435-9792) to manually add your pet to your record locator.

4.Visit the Ticket Counter First: Day of Departure.

On travel day, you cannot use the self-service kiosks or mobile boarding passes immediately. You must bring your pet and carrier to the airport ticket counter to pay the $95 pet fee and receive your physical boarding clearance.

5.Obtain Your Pet Fare Receipt:Before Security.

Once the ticket agent processes your payment, they will issue a plastic tag to attach to your pet's carrier, indicating your pet has been cleared and paid for. Keep this receipt handy for the security checkpoint.

You can check airlines and country guides at - Pet Travel Country Guides | Import & Export Rules by Country | Pet Holiday Club

Tips for Flying With Your Pet on Southwest

Navigating Southwest's open-seating boarding process with a pet requires unique tactical planning. Use these strategies to make your journey stress-free:

  • Leverage EarlyBird Check-In: Southwest does not assign seats. Because you need to secure a seat with maximum under-seat space, buying EarlyBird Check-In or checking in exactly 24 hours in advance is highly recommended. This ensures you board early enough to select a row with optimal space.

  • Avoid the bulkhead rows: While bulkhead seats (the front row of the cabin) offer great legroom, they do not have seats in front of them. This means there is no under-seat storage space, making it physically impossible to keep your pet carrier with you during takeoff and landing.

  • Target the middle seat for wider carriers: On Southwest’s Boeing 737 aircraft, the under-seat space beneath the middle seat is slightly wider than the space under the window or aisle seats. If your carrier is wide, sitting in the middle seat can provide your pet with a bit of extra room.

  • Carry physical health records: While Southwest does not require a formal veterinary health certificate for domestic flights, certain state agricultural departments can request proof of rabies vaccination upon landing. Always carry a printed copy of your pet’s current vaccination records.

  • Doff the harness at TSA: When passing through airport security, you must remove your pet from their carrier. You will walk your pet through the metal detector while the carrier passes through the X-ray machine. Use a simple, non-metallic harness and leash to make this process rapid and secure.

Pet Travel Comparison: Southwest vs. Competitors

Comparing Southwest’s pet-friendly parameters to those of other major U.S. carriers highlights the financial benefits and routing limitations of their policy.

Metric

Southwest Airlines

Delta Air Lines

United Airlines

American Airlines

One-Way Pet Fee

$95

$150

$150

$150

Max Carrier Height

8.5 Inches

11 Inches

11 Inches

9 Inches

Weight Limit

No official limit

No official limit

No official limit

Max 20 lbs (incl. carrier)

International Travel

Strictly Banned

Allowed on select routes

Allowed on select routes

Allowed on select routes

Checked Cargo Option

No

Military/FSO Only

Military/FSO Only

Military Only

Max Pets Per Flight

6 carriers total

4-6 carriers total

4-6 carriers total

Up to 7 carriers total

Frequently Asked Questions

Q: How much does Southwest charge for pets?

Southwest charges $95 each way per pet carrier. If you are flying round-trip, the total cost is $190, which is paid at the airport ticket counter during check-in.

Q: Can my pet fly on Southwest international flights?

No, Southwest Airlines does not allow pets to travel on any international routes. This pet ban applies to all flights to Mexico, Central America, and the Caribbean.

Q: What size carrier can I use on Southwest?

For soft-sided carriers, the maximum recommended dimensions are 18.5 inches long, 13.5 inches wide, and 8.5 inches high. Hard-sided carriers must not exceed 13.5 inches long, 8.5 inches wide, and 8.5 inches high.

Q: Can two pets travel in one carrier on Southwest?

Yes, Southwest allows you to travel with two small puppies, kittens, dogs, or cats of the same species in a single carrier. You will only be charged a single $95 fee.

Q: Can I ship a large dog via Southwest Cargo?

No, Southwest Airlines does not offer checked baggage or cargo transportation services for live animals. All pets traveling on Southwest must be small enough to fit inside a cabin carrier.

Q: Can I fly with my dog to Hawaii on Southwest?

No, Southwest Airlines strictly prohibits pets on all flights traveling to, from, or connecting through Hawaii due to the state’s complex rabies quarantine requirements.

Before flying with your pet on Southwest Airlines, make sure you have the right documentation for your destination. Pet Holiday Club covers 190+ countries with government-sourced, vet-verified pet travel checklists at petholidayclub.com — so you arrive prepared, not refused.

Frequently Asked Questions

The Southwest Airlines pet fee is a non-refundable $95 each way, per pet carrier. This Pet Fare must be paid at the ticket counter on your day of travel when you check in for your flight.
No, Southwest does not allow pets to travel on international flights. According to the Southwest Airlines pet policy, pets are only permitted in the cabin on domestic flights within the United States.
To fly in the cabin, your pet must be a small, vaccinated domestic cat or dog. The pet must remain in an approved carrier that fits under the seat in front of you for the entire duration of the flight.
Yes, you should book your pet's spot in advance as Southwest only allows a limited number of pets per flight. You can make the reservation by calling Southwest Airlines directly after booking your own ticket.
Your pet carrier must be small enough to fit under the seat, with maximum dimensions of 18.5” L x 8.5” H x 13.5” W. The carrier must be well-ventilated and secure to prevent your pet from escaping during the flight.

Written by

Anano Gudushauri

Pet Holiday Club

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