Flying With a Dog on American Airlines: The 20 lb Rule, Fees and Where You Can Go

American Airlines is stricter than its main rivals in one important way: it weighs your dog. Where Delta and United judge only by whether the carrier fits under the seat, American adds a limit on the combined weight of dog and carrier, and its staff put both on the scales at check in. That single rule catches out a good many owners whose dogs have flown happily on other airlines. This guide sets out what American allows, taken from the airline's own pets page as it stood in the autumn of 2026, together with the practical points that matter on the day.

What American Allows, in Brief

A small dog can travel in the cabin for $150 per carrier, each way, so a return trip costs $300. Dog and carrier together must weigh no more than 20 lb. Cabin pets are accepted within the 48 contiguous states and on flights to and from Canada, Alaska, Mexico, Puerto Rico and a few Caribbean islands, on journeys of up to 12 hours. American does not take pets in the cabin across the Atlantic or the Pacific, or to or from Hawaii, and it checks pets into the hold only for military and diplomatic staff. For most owners, then, American is an airline for a small dog on a trip within North America.

The 20 lb Rule

The rule is stated plainly: the total weight of your pet and its carrier must not exceed 20 pounds, and the airline says it will weigh them at check in. A soft carrier weighs two or three pounds empty, and a blanket and a water bowl add a little more, so the dog itself needs to weigh about 17 lb or less. Weigh your dog in its carrier at home on the bathroom scales before you book, not at the airport. If you are within a pound of the limit, a lighter carrier and a trim before the trip can make the difference, but a dog of 22 lb is not going to qualify, and it is kinder to know that early.

Weight is not the only test. Your dog must fit comfortably inside the closed carrier and stay there, under the seat in front of you, for the entire flight. It must be at least 8 weeks old to fly within the United States. American assumes no liability for the health of a carry on pet, which is worth knowing, and it expects the animal to be calm and contained from the moment you enter the terminal.

The Carrier

American recommends a soft sided carrier of up to 18 by 11 by 11 inches, which it accepts on all its flights. Hard sided carriers must be smaller, at 19 by 13 by 9 inches on American's own mainline aircraft and only 16 by 12 by 8 inches on the regional jets that fly as American Eagle. Since many journeys begin or end on a regional jet, a soft carrier is by far the safer choice. It must be secure, padded, made of water repellent material and ventilated with mesh on three or more sides, and it may be squashed a little to fit under the seat, though not so much that the dog is cramped.

You may bring the pet carrier and one other item, either a personal item such as a handbag or a carry on bag for the overhead locker, but not both. That is tighter than the normal allowance, so plan your packing around it. Pet strollers have to be checked in at the ticket counter, and the normal charges for checked bags apply.

How Many Pets, and Which Seats

The number of carriers American accepts depends on the aircraft. On its larger aircraft the total can be as high as twenty across the cabins, but on the smallest regional jets only one carrier is allowed in first class and five in the main cabin. On its long haul aircraft, pets are not permitted in the premium cabins at all, because there is no storage space under those seats. The practical lesson is the same as on every airline, which is to add your dog to the booking as early as you can.

You cannot sit in a bulkhead row or an exit row with a pet. On most of American's single aisle aircraft pets travel in the main cabin only. If you are choosing a seat, a window keeps your dog away from the trolley and passing feet, and a seat towards the front of the main cabin gets you off the aircraft and to a relief area sooner.

Where American Will Not Take a Dog in the Cabin

American does not accept carry on pets on transatlantic or transpacific flights, to or from Hawaii, to Jamaica, or to or from Argentina, Brazil, Chile, Colombia and Uruguay. It also refuses to carry a dog in the cabin if it has been in any country the CDC lists as high risk for rabies during the previous six months, which matters if your dog has travelled widely. If your plans involve Europe, you will need a different airline, and our guide to taking a dog from the US to Europe explains which ones carry dogs in the cabin.

For Mexico, your dog needs a screwworm inspection certificate completed by a vet accredited by the Department of Agriculture and issued within five days before entering the country. American checks it at the airport during check in, and the rule applies to service dogs as well as pets. Our guide to taking a dog to Mexico explains that certificate and the second one you need in order to return.

Larger Dogs, Heat and the Hold

American accepts checked pets at the ticket counter only for active duty military personnel and State Department Foreign Service staff travelling on official orders, at $200 per kennel. For everyone else, a dog too big for the cabin travels through American Airlines Cargo, a separate service with its own booking process and prices, which are confirmed when you book. That is a very different undertaking from carrying a small dog on board, and our guide to flying a dog in the hold is the place to start if you are considering it.

The rules American applies to animals in the hold show how seriously it takes the risks. It does not accept flat faced or snub nosed dogs of any mix as checked pets, and its list runs from bulldogs, pugs and boxers to mastiffs, Shih Tzus and Staffordshire Bull Terriers. It will not accept a pet if the current or forecast temperature is above 85°F at any point on the journey, or below 45°F on the ground, and between May and September it will not carry pets in the hold through Phoenix, Tucson, Las Vegas or Palm Springs at all. Those limits exist because the danger to a dog in the hold lies in the waiting on the ground, not in the flight.

Sedation

American will not accept a pet that has been sedated or tranquillised, in the cabin or in the hold. It follows the advice of the American Veterinary Medical Association, which is that animals given sedatives are at higher risk of breathing and heart problems at altitude. Owners of nervous dogs are sometimes tempted to give something to take the edge off, and it is a mistake that can end with the dog being refused at the counter. If your dog is an anxious traveller, speak to your vet weeks ahead about what is safe, and put the effort into getting the dog used to its carrier, which does far more good.

Booking and the Day of Travel

You can add a carry on pet to an existing booking on American's website or in its app, under additional services, where you agree to the requirements and choose the flights the pet will travel on. The fee is paid at the airport, by card, at the ticket counter, where staff check that the dog and carrier meet the rules. If part of your journey is on a partner airline, American does not collect that airline's pet fee or guarantee that it will carry your dog, so check with each airline on the ticket.

Give yourself extra time at the airport, because the check at the counter cannot be hurried. At security you will carry your dog through the metal detector while the empty carrier goes through the X-ray machine, as the TSA requires, so keep a lead on it. Walk your dog well before you set off, feed it lightly some hours beforehand, and use a pet relief area before boarding. Our guide to training your dog to travel explains how to prepare a dog for hours in a carrier, and our complete guide to flying with a dog covers the rest. If you are returning from abroad, your dog also needs a CDC Dog Import Form, a microchip and to be at least six months old.

A Closing Thought

American works well for a small dog on a domestic flight or a short trip to Canada or Mexico, provided you have weighed dog and carrier together and come in under 20 lb. It is the wrong airline for Europe, for Hawaii and for any dog near the weight limit. Do the weighing at home, choose a soft carrier, add the dog to your booking early, and arrive at the counter with time in hand.