Can Pets Fly on Southwest Airlines? | Pet Fees And Cabin Rules

Small, vaccinated cats and dogs can ride in the cabin in a carrier under the seat on many domestic routes, with limited pet spaces on each flight.

Flying with a pet sounds easy until you hit the real-world snags: the carrier that won’t slide under the seat, the flight that’s “sold out” for pets, the seat row that has no under-seat space, or the route that blocks pet travel no matter what. Southwest can be one of the simpler U.S. options for in-cabin pet travel, but it’s strict about the basics.

This article lays out the rules that decide if your pet can board, the steps that keep check-in smooth, and the small moves that help your pet stay calm from curb to gate.

What Southwest means by “pet” on a flight

Southwest’s pet travel option is built for small domestic cats and dogs that can stay inside a carrier that fits under the seat in front of you. If your animal can’t stay in a carrier for the full flight, Southwest’s pet option isn’t a match.

Southwest does not transport pets as checked baggage or cargo. Your pet flies with you in the cabin or not at all. That single rule shapes the rest: carrier size, seat selection, and the limited number of pet carriers allowed onboard.

Pets allowed

• Domestic cats
• Domestic dogs

Pets not accepted under the pet program

• Animals other than cats or dogs
• Pets that can’t fit in a carrier under the seat
• Pets traveling with an unaccompanied minor

Can Pets Fly on Southwest Airlines? Cabin rules that decide

Yes, pets can fly on Southwest when they meet the cabin-only rules: your animal is a small domestic cat or dog, it stays inside a carrier that fits under the seat, and you’ve secured one of the pet spaces on that flight.

Route rules matter just as much as the carrier. Some destinations and itineraries don’t accept pets, even when your carrier is perfect and your pet is calm. Build your plan around the route first, then lock in the pet reservation.

Domestic routes and destination limits

Southwest’s pet program is tied to domestic flying. If your trip includes an international segment, plan on a different airline or a different travel plan. Also watch Hawaii: pet travel rules and fees differ on eligible interisland flying, and some mainland-to-island plans won’t accept pets.

Limited pet spaces per flight

Southwest caps how many pet carriers can be in the cabin on each flight. That cap is why timing matters. A flight can still have open seats for people while being full for pets.

If you’re traveling during peak times (holiday weekends, spring break, Sunday evenings), treat the pet spot like a scarce seat. Reserve it early, and keep a backup flight time in mind.

How to reserve a pet spot and pay the fee

Adding a pet is not something to leave for the airport. Southwest asks customers to reserve in advance by phone so the airline can confirm pet space on your specific flight. Book your human ticket, then call right after to attach the pet reservation.

The pet fare is charged per one-way trip and per carrier. Southwest publishes the current one-way carryon pet charges (including a mainland rate and an interisland Hawaii rate) on Southwest’s Optional Travel Charges page. Southwest also notes the pet fare is paid at the airport ticket counter and can be refundable when you cancel your reservation, so it’s smart to read the current fee notes before travel day.

One carrier per customer, with a practical twist

Each ticketed customer may bring one pet carrier. Southwest also allows up to two cats or two dogs of the same species in a single carrier, as long as they fit comfortably. That can help a bonded pair stay together, but it raises the comfort bar. Both animals still need room to turn and settle without being pressed against the walls.

If you have two carriers, you’ll need two ticketed customers. Southwest’s rule is about carriers, not pets.

Choosing a carrier that passes the under-seat test

Most pet travel problems start with a carrier that’s too tall, too rigid, or built with a frame that won’t flex when seat space narrows. On Southwest, your pet must stay in the carrier, and the carrier must fit under the seat in front of you.

Before you buy a carrier, do two checks at home: measure, then test-slide. Set a chair in front of a couch or another chair to mimic the under-seat gap. If the carrier scrapes, catches, or needs a hard shove, pick a different model.

Soft-sided vs. hard-sided

Soft-sided carriers tend to work better for under-seat spaces because the corners can flex a bit. Hard-sided carriers can work, but they leave less margin when the seat legs or rails narrow the opening.

Whichever type you choose, prioritize steady ventilation, secure zippers, and a base that stays flat when you lift it. A sagging base can make your pet slide and panic.

Comfort rules that keep your pet calm

Your pet should be able to stand, turn, and lie down naturally inside the carrier. That’s the comfort baseline. If your pet has to crouch the whole time, the trip can turn stressful fast.

Line the carrier with a familiar blanket or T-shirt that smells like home. It’s a small move that can reduce whining and scratching.

What to expect at the airport and on the plane

Once the pet reservation is attached to your flight, the travel flow is routine with a few extra steps. The goal is to avoid last-minute surprises that make your pet tense.

Ticket counter first

Plan to stop at the ticket counter to pay the pet fare and confirm everything is marked correctly on your reservation. Build extra time into your arrival so you’re not rushing from the counter straight into a long security line.

Security screening basics

At the checkpoint, expect to take your pet out of the carrier. The carrier goes through the X-ray, and you carry your pet through the metal detector. A secure harness and leash help a lot here.

If your cat is a flight risk, ask for a private screening room before you open the carrier. It can prevent a nightmare chase in a crowded terminal.

Boarding and under-seat placement

Once onboard, the carrier stays under the seat in front of you for taxi, takeoff, and landing. Aim the carrier opening toward you, not the aisle, so you can check on your pet and block some foot traffic.

Seat choice matters. Exit rows don’t work for under-seat storage, and bulkhead seats can be tricky because the under-seat area may not be available. Pick a standard row with a normal under-seat space so you aren’t hunting for a new seat at the last minute.

Connecting flights and layovers

If you have a connection, plan for a quick reset between flights. Find a quiet corner away from heavy foot traffic, check the carrier liner, offer a few sips of water, and keep the carrier closed. A calm layover keeps the second flight easier.

Try to avoid tight connections. Rushing through a terminal with a pet carrier can lead to bumps, loud noises, and a stressed animal before you even board.

Southwest pet policy details that trip people up

Most denied-boardings happen because one rule was treated like a suggestion. These points deserve full attention.

Pets stay in the carrier the whole time

Southwest’s pet program is built around containment. You can’t take your dog out mid-flight, and you can’t set a cat on your lap. If your pet won’t tolerate the carrier while you’re seated, plan another travel method.

Pet spaces can sell out early

You can have a paid ticket and still miss out on a pet slot. Call early after booking. If your flight is full for pets, changing to a different departure time is often the cleanest fix.

Route rules can override everything

Even a calm pet in a great carrier can’t fly on a route that blocks pets. Confirm your exact city pair, connection plan, and any island segments before you commit to lodging and ground plans.

Pets flying on Southwest Airlines with fee and rule breakdown

This table pulls the core rules into one place so you can spot deal-breakers early and plan the parts you control.

Rule	What it means on travel day	Why it matters
Eligible pets	Small domestic cats and dogs only	Other animals aren’t accepted under the pet program
Minimum age	Pet must be at least 8 weeks old	Young puppies and kittens can be turned away
Where pets ride	Cabin only, under the seat	No checked-pet or cargo option on Southwest
Reservation	Reserve in advance by phone; space is limited per flight	Your seat can be confirmed while pet space is full
Pet fare	Charged per one-way trip, per carrier	Round trips cost two pet fares per carrier
How you pay	Pay at the ticket counter with accepted credit cards	Plan counter time before security
Carriers per customer	One carrier per ticketed customer	Two carriers require two ticketed customers
Pets per carrier	Up to two of the same species in one carrier	Only works if both fit comfortably
Carrier placement	Must fit under the seat in front of you	Oversized carriers can create a gate problem
Destination limits	Some destinations and itineraries don’t accept pets	Route choice can block pet travel even when other rules are met

Comfort planning that makes the trip easier for your pet

Rules get you onboard. Comfort choices get you through the flight without drama. A calm pet also makes your day calmer, and it’s worth planning for.

Practice the carrier before travel day

Don’t introduce the carrier the night before your flight. Set it up at home with the door open, add a familiar blanket, and drop treats nearby. Then move the treats inside the carrier. The goal is for your pet to treat the carrier like a safe den, not a trap.

Pick a flight time that matches your pet’s routine

Many pets do better when their normal sleep window lines up with the flight. If your dog naps mid-morning, a mid-morning departure can be smoother than a late-night flight that keeps them alert and restless.

Food and water timing

Give a light meal well before you leave for the airport so your pet isn’t traveling on a full stomach. Offer water, then taper off close to boarding to reduce accidents. Pack wipes and a spare liner so a small mess doesn’t ruin the whole trip.

Skip new meds unless your vet already tested them

New sedatives can backfire. Some pets get wobbly, anxious, or nauseated, and you don’t want to find that out in a security line. If your vet recommends medication for travel, do a trial dose on a normal day first so you know how your pet reacts.

What documents and prep items you should have ready

Southwest describes in-cabin pet travel around small, vaccinated cats and dogs. That makes vaccination records worth carrying, even when nobody asks. Save a clear photo of your pet’s vaccine record on your phone and keep a printed copy in your bag if you like backups.

Pack with the “two-minute cleanup” mindset. A few small items can save your clothes, your carrier, and your mood.

Smart items to bring in your personal bag

• Harness and leash (even for cats)
• Waste bags and a few paper towels
• Unscented wipes
• Spare absorbent pad or carrier liner
• Collapsible bowl for water after you exit
• Small treat bag for calm moments at the gate

Day-of-travel checklist for a smooth Southwest pet flight

Use this checklist as your last pass before you lock the door. It’s built around the moments where pet travel most often goes sideways: counter, security, boarding, and the first ten minutes in your seat.

When	What to do	What to pack or stage
24–48 hours out	Call to confirm the pet reservation is attached to your itinerary	Reservation number, flight times, backup flight options
Night before	Line the carrier and test zippers, clips, and ventilation	Absorbent pad, small blanket, spare liner
Before leaving home	Potty break or litter box time, then settle your pet in	Harness, leash, waste bags, wipes
At the ticket counter	Pay the pet fare and confirm your pet is noted on the booking	Credit card, ID, vaccination record photo
At security	Carry your pet through screening; send the carrier through X-ray	Leash, calm voice, request a private room if needed
At the gate	Keep the carrier closed and away from heavy foot traffic	Light cover cloth, a few treats
Onboard	Slide the carrier under the seat and check airflow	Spare pad, wipes, small towel
After landing	Wait for the aisle to clear, then lift the carrier level	Water and a collapsible bowl for after you exit

When Southwest is not the right fit

If your dog is too large for an under-seat carrier, Southwest won’t work for pet travel. The same is true when your trip includes an international segment or a route that blocks pets. In those cases, look at airlines with a different pet transport program, or plan ground travel.

Also be honest about temperament. If your pet panics in a carrier, fights zippers, or can’t settle in a confined space, the kinder choice may be a trusted pet sitter at home.

One last check before you book

Policies can change, and small details like fees and route notes can shift. Before you commit, read Southwest’s current Pet Policy page, then confirm your flight still has pet space by phone. If those steps line up, the rest is good planning and a carrier that truly fits.