Yes, a small cat or dog can ride in the cabin in a carrier for a pet fee, with route limits and a cap on pets per flight.
Flying with a pet can feel like a small logistics project: booking the right way, choosing a carrier that fits under the seat, and getting through the airport without a meltdown. Southwest lets many travelers bring a small cat or dog in the cabin, but the rules are tight. If you know the deal before you buy your ticket, you can avoid the last-minute “sorry, we’re full” moment at the airport.
Bringing A Pet On Southwest Airlines With Cabin Limits
Southwest’s pet option is built around one idea: small pets travel in the passenger cabin, under the seat, inside a carrier. There’s no pet cargo service. That means your pet stays near you, yet the size and seating limits are strict.
Pets Southwest accepts
For the standard pet option, Southwest accepts vaccinated domestic cats and dogs that fit in a carrier under the seat. If your pet can’t fit under the seat in a carrier, Southwest won’t work for that trip.
Routes where the pet option works
The in-cabin pet option is for domestic itineraries, with destination limits. Hawaii is the big one: Southwest does not allow pets on flights to or from Hawaii, while it does accept pets on flights between Hawaiian Islands. If your trip includes an island hop, confirm the exact city pair before you book lodging.
How many pets can be on one flight
Southwest caps the number of pet carriers per flight. Seats can sell out even when the plane still has open seats for people, so book your pet spot early. If you switch flights, re-check that a pet spot is available on the new departure.
What It Costs And How You Pay
Southwest charges a one-way carry-on pet fee per pet carrier, per flight. The fee differs by region and can change, so use the official fee page as the source of record: Southwest’s Optional Travel Charges.
Many travelers miss one detail: you generally pay the pet fee at the airport ticket counter, not during online checkout. Build that stop into your arrival time so you’re not rushing to the gate.
Carrier Rules That Decide Whether You Board
Your carrier is the whole game. Southwest treats a pet carrier as a carry-on style item, and it must fit under the seat. Soft-sided carriers are popular since they can flex to slide under tighter seats, but hard-sided carriers can work if they meet the size limit and fit.
Size, structure, and ventilation
Measure your carrier and test it under a chair at home with similar clearance. Many travelers aim for a carrier near 18.5 inches long, 13.5 inches wide, and 9.5 inches high, since that’s a common cap Southwest cites across pet policy summaries.
One pet per carrier, with one common exception
In most cases, you’ll use one pet per carrier. Policy summaries often allow two pets of the same species in one carrier if they fit comfortably and can stand and turn. If you plan to double up, test the real fit at home with the carrier fully closed.
Where you can sit
You need a seat with under-seat storage in front of you. That rules out bulkhead rows and any seat without space under the seat ahead. Exit rows are a no-go for a pet carrier. When you board, pick a standard row seat and slide the carrier fully under the seat in front.
Booking Steps That Prevent Gate Problems
Pet space is limited, so booking is not just “buy a ticket and show up.” Pick an eligible domestic itinerary, add the pet reservation early, and plan your carry-on setup around the carrier since it counts toward your carry-on allowance.
Flight timing can help, too. Early departures often mean cooler temps and fewer late-day delays. Direct flights remove the risk of long gate sits and missed connections.
Do a fast carry-on count
Your pet carrier takes the place of a personal item or carry-on, depending on your setup. Before you leave home, decide what your second item will be and keep it small enough to stow without drama.
Table: Southwest Cabin Pet Rules At A Glance
The checklist below condenses the points that most often decide if a pet can travel on the flight you booked.
| Rule Area | What To Expect | What To Do Before Travel Day |
|---|---|---|
| Pets accepted | Small domestic cats and dogs in the cabin | Confirm your pet fits in a carrier under the seat |
| Where pets ride | In a carrier under the seat in front of you | Practice calm carrier time at home |
| Carrier build | Leak-resistant, ventilated, secure zipper or latch | Choose a carrier with airflow and a firm base |
| Carrier sizing | Must fit under-seat; common max is near 18.5″ x 13.5″ x 9.5″ | Measure your carrier and test under a seat-style space |
| Seat limits | No exit rows; avoid bulkhead rows and seats without under-seat space | Board ready to pick a standard row seat fast |
| Flight limits | Pet carrier slots per flight are capped | Add the pet reservation early |
| Hawaii restriction | No pets on flights to/from Hawaii; inter-island routes can allow pets | Confirm your exact route before booking lodging |
| Paying the fee | One-way pet fee per carrier, per flight | Arrive early for the ticket counter stop |
| Security screening | Pet comes out of carrier; carrier goes through X-ray | Use a snug harness and short leash |
Travel Day Walkthrough From Curb To Seat
The airport is where most plans fall apart. A basic routine keeps things smooth.
At the ticket counter
Plan to stop at the ticket counter to pay the pet fee and get any required paperwork from the agent. Arrive with time to spare, since counter lines can spike during peak hours.
At TSA screening
TSA screening is the tricky moment. You’ll take your pet out of the carrier and carry the pet through the metal detector while the empty carrier goes through the X-ray. A snug harness and leash help prevent a dash through the checkpoint. The U.S. Department of Transportation page on Flying with a Pet explains what many travelers should expect.
At the gate and onboard
Keep your pet in the carrier in the gate area, during boarding, and for the full flight. Once you pick a seat, stow the carrier under the seat in front of you right away. Don’t put the carrier on your lap or in the overhead bin.
Common Snags And How To Avoid Them
Most issues come from three things: carrier size, seat choice, and running out of pet spots.
- Carrier fit: Test your carrier before the trip. Soft-sided carriers can compress a bit, but don’t count on forcing a tall carrier under a tight seat.
- Seat choice: If you sit in a bulkhead row, you may be asked to move. Scan for a standard row seat with under-seat space.
- Counter timing: If you still need to pay the pet fee, the counter stop can break your timeline. Treat it like checking a bag.
Comfort Tips That Help Most Pets
When pets struggle on planes, it’s often noise, motion, and the unfamiliar routine. You can’t control the flight, yet you can control the basics: carrier comfort, practice, and your own calm.
Set up the carrier for a long sit
Use an absorbent pad under a thin blanket. Skip thick beds that steal interior space. Your pet should be able to stand and turn without hitting the top.
Practice in short sessions
Start with the carrier open and treats inside. Work up to calm door-closed sessions while you walk around the house. By travel day, the carrier should feel familiar.
Food, water, and medication
Many owners feed a light meal well before heading to the airport and offer small sips of water on a normal schedule. If your pet needs medication or has a history of panic, talk with your veterinarian before the trip and follow that plan.
When Southwest Is Not A Good Fit
Some trips don’t line up with Southwest’s pet setup. If your pet is too tall for an under-seat carrier, you’ll need a different plan. That might mean driving, choosing a pet sitter, or selecting an airline that offers another transport option.
Trips with long layovers can be rough on pets, too. If you can’t get a direct flight, pick the shortest connection you can find and map out pet relief areas in each terminal.
Table: Planning Your Trip By Pet Size And Temperament
This table helps you choose flights and gear based on the pet you’re traveling with, not a generic checklist.
| Pet Profile | Flight Choice That Fits | Carrier And Handling Notes |
|---|---|---|
| Small calm cat | Direct flight, any boarding group | Light carrier cover can reduce visual stress |
| Small calm dog | Direct flight, early day departure | Practice “settle” in carrier with the zipper closed |
| Nervous pet | Shortest route with the fewest delays | Carrier practice daily for a week or more |
| Older pet | Direct flight, avoid long airport waits | Extra padding for joints, yet keep headroom |
| Heat-sensitive pet | Morning flight, avoid long outdoor waits | Carry a small water dish after security |
| Chatty pet | Midweek flight times when cabins are quieter | Bring a chew-safe toy that stays inside the carrier |
What To Pack So You’re Not Scrambling
Once your pet is in the carrier, you can’t reach much during takeoff and landing. Pack small items that solve common problems without taking over your bag.
- Harness and leash: For the security checkpoint and any gate-area breaks.
- Absorbent pads: One in the carrier, one spare in a zip bag.
- Collapsible bowl: For water after security and after landing.
- Treats: Small pieces that your pet can chew quietly.
- Wipes: Quick cleanup for paws and carrier corners.
A Preflight Checklist You Can Finish In 10 Minutes
- Confirm your itinerary is eligible for in-cabin pets.
- Confirm your pet reservation is attached to your booking.
- Measure the carrier and test it under a seat-style space.
- Pack a leash, pads, and wipes in a zip bag.
- Arrive early enough for the ticket counter stop.
If you stick to these steps, the trip usually turns into a normal flight with one extra carry-on under the seat.
References & Sources
- Southwest Airlines.“Optional Travel Charges.”Lists the one-way carry-on pet fee and related counter purchase fees.
- U.S. Department of Transportation.“Flying with a Pet.”Explains common airline cabin pet restrictions and what to expect at the airport.
