Airline Pet Policies Compared: In-Cabin, Checked, and Cargo

Which airlines take pets in the cabin, size and fee rules, and the shrinking options for larger dogs.

By WarBird Flight editors · Updated September 19, 2026 · 2 min read

In-cabin

Delta, United, American, Alaska, Southwest, JetBlue, and Frontier accept small dogs and cats in a soft carrier under the seat on most domestic routes, for a fee each way, with a cap on pets per flight. Hawaii and international routes have extra restrictions or bans.

Checked and cargo

Most US carriers stopped accepting pets as checked baggage. Alaska still does on many routes; United and American offer cargo programs through separate divisions with their own booking process. Breed restrictions and summer heat embargoes apply.

The carrier has to fit under the seat

An in-cabin pet travels in a carrier that stays under the seat in front of you for the whole flight, and the pet must be able to stand up and turn around in it — that combination, not the animal's weight alone, is what decides whether it can fly in the cabin. Under-seat space differs by aircraft, and soft-sided carriers are expected because they compress. Measure your pet and your carrier against the specific airline's published dimensions before you buy, because a carrier that is too tall is turned away at the gate. A pet in the cabin also counts as your carry-on on most airlines, so you would check or gate-check your own bag.

Fewer options for larger dogs

Anything too big for an under-seat carrier has narrowing choices. Most US carriers no longer take pets as checked baggage, and the cabin is limited to small animals, so a large dog usually means a cargo program — booked through a separate division with its own process — or a pet-focused charter. Cargo programs pause during summer heat embargoes and exclude certain snub-nosed breeds that do not tolerate temperature swings. The exceptions are trained service animals, which travel in the cabin under separate rules and cannot be charged a pet fee. If your dog is large, sort the routing early; the flight options may shape the trip more than the fare does.

International

Health certificates, microchips, rabies vaccination timing, and in some countries quarantine. Start months ahead. The airline rules are the easy part.

Book the pet with the seat

Pet spaces sell out. Call (708) 866-8751 and the agent adds the pet at booking and confirms the carrier dimensions the airline accepts. Policies reviewed September 2026.