In the cabin: cats and dogs, with no weight or breed limit
United's own rules, in plain English. Confirm the current details at united.com.
United does not publish a weight limit or a breed restriction for an in-cabin pet. Snub-nosed (brachycephalic) breeds that get turned away as checked pets on other airlines are fine in United's cabin, because the only test is whether the carrier fits fully under the seat in front of you. Hard-sided carriers are allowed up to 17.5 x 12 x 9 in; soft-sided carriers are allowed up to 18 x 11 x 11 in. Either way, the carrier must be ventilated and your pet must be able to stand and turn inside it.
For international travel the minimum is stricter and species-specific: a dog entering the US from abroad must be at least 6 months old under CDC rules, and a kitten must be at least 4 months old to meet vaccination requirements. Those are separate, stricter thresholds tied specifically to crossing a border, not the general domestic rule.
Because United's pet program is cabin-only, there's no cargo hold option for the public, the temperature embargoes that apply to some other airlines' cargo pet programs simply don't apply here the same way. That's a genuine byproduct of PetSafe being discontinued, not a gap in the rules.
There's no fixed advance-booking window published for a carry-on pet, but spots are limited per flight and United says to arrange it before you travel. Checked pets (military / State Dept only) need to be arranged with Reservations ahead of time.
Too big for the cabin? There's no public checked or cargo option
The single most important thing to know if your pet won't fit under the seat.
United discontinued its PetSafe cargo program, which used to let a larger pet fly as cargo on a separate booking. That option no longer exists for the general public.
The only pets United still checks or ships as cargo belong to active-duty US Military and State Department Foreign Service personnel traveling on official orders. For everyone else, if your pet doesn't fit under the seat, United does not have a way to fly it, don't bring a large dog to the counter expecting to check it.
American and Delta both restrict checked pets to military/State Dept the same way United does, so if your pet is too big for any of their cabins, none of the big three US network carriers can fly it for you as a general traveler. Call us and we'll check whether another carrier or a pet-specific cargo shipper is a better fit.
How many pets, and the aircraft rule that catches people out
This is airline-specific, not generic, and it's easy to get wrong.
On most United flights you can bring up to two pets, but only the first travels free at your feet. The second pet has to travel in a carrier in a separate, purchased seat next to you, it is not a second free carry-on.
On United's A319, A320, A321neo and Boeing 737 family aircraft, which have limited under-seat space, only one pet is allowed on the entire flight, not one per passenger. Buying a second seat doesn't change that on these aircraft; the aircraft type itself is the hard limit. If your itinerary includes a smaller connecting aircraft, confirm the pet spot is actually available before you build the rest of the trip around it.
Where an in-cabin pet isn't allowed, and where it is
The list is longer than most people expect. Always confirm your exact country at united.com.
United does not allow an in-cabin pet to, from, or through: Australia, Barbados, Brazil, Cuba, Dominica, the Dominican Republic, French Polynesia, Greenland, Guam, Guyana, Hawaii, Hong Kong, Iceland, Ireland, Jamaica, the Marshall Islands, Micronesia, Mongolia, Morocco, New Zealand, the Northern Mariana Islands, Palau, the Philippines, St. Kitts & Nevis, South Africa, Spain, Sweden, Taiwan, Thailand, Trinidad & Tobago, the UAE, the UK, and Vietnam. Hawaii is banned domestically as well as internationally, so it isn't just a passport question.
One contrast worth knowing for our market: Colombia is NOT on this list. United can carry an in-cabin pet to or from Colombia, a genuine difference from some other US airlines that do ban it. If your trip is to Bogotá, Medellín or Cartagena, that's worth confirming with us; a route that gets refused on one airline may still work on United.
There are a few narrower route quirks too: in-cabin pets are prohibited to and from Bilbao, Spain specifically, and Guam has its own routing wrinkle, pets can travel Guam→Tokyo-Narita or to the US mainland, but not back to Guam, and the Kaohsiung↔Tokyo-Narita and Taipei↔Guam routes don't carry pets either. These are the kind of details that only show up if you check the exact routing, not just the destination country.
Service animals vs. emotional-support animals
Getting the category wrong can mean paying the pet fee you didn't expect.
United recognizes a service animal as a trained dog that performs work or tasks for a person with a disability. Up to two trained service dogs travel free per passenger, under United's own accessibility policy, see our special assistance help for the paperwork, or call us and we'll set it up.
Emotional-support and therapy animals are not service animals on United. They travel under the ordinary paid pet policy, in a carrier, subject to the same size limits, the same banned-destination list, and the same fee as any other pet. If you're not sure which category applies to your animal, don't guess at the airport; call us and we'll route it correctly ahead of time.
Service-animal and pet policies carry real rules that vary and change; United sets and updates them. Always confirm current requirements at united.com before you travel.
The fee, quoted, not guessed
One number United does publish.
United charges $150 each way per pet for a carry-on pet (cats or dogs only). A second pet in its own purchased seat is billed as that seat's fare, on top of the pet fee. Trained service dogs travel free. Fees like this change, so treat the figure above as a starting point, confirm the current amount at united.com, or call us and we'll verify it along with your carrier size, aircraft and route before anything is booked.
Before you book, the checklist
A few minutes now saves a ruined trip at the counter.
- Does your carrier fit fully under the seat? Hard-sided up to 17.5 x 12 x 9 in, soft-sided up to 18 x 11 x 11 in, weight and breed don't matter
- Is an in-cabin pet even allowed on your route? A long banned-country list includes Brazil and Hawaii. Colombia is not on it
- Bringing a 2nd pet? It needs its own purchased seat, and isn't an option at all on A319/A320-family or 737 aircraft
- Destination entry rules, vaccination records, health certificates, sometimes import permits; international pups/kittens face stricter minimum ages
- Too big for the cabin? United has no public checked or cargo option, confirm before you assume it's covered
Check the aircraft before you buy a second seat for a second pet. On A319, A320-family and 737 aircraft, United allows only one pet per flight no matter how many seats you purchase. Tell us your route and we'll confirm the aircraft and the pet spot before you build the rest of the trip around it.
Frequently asked
Is there a weight limit for a pet in the cabin on United?+
Can I check my pet as baggage or ship it as cargo on United?+
How many pets can I bring, and does a second pet need its own seat?+
Where can't I bring an in-cabin pet on United?+
Does United accept emotional-support animals?+
Contact options
Reach United directly, or let us confirm your pet and book the spot.
Contact United Airlines directly
The airline's own official channels, free.
These are United's own channels; confirm current pet rules at united.com.
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