Underseat guideshttps://www.underseatpets.com/Airline pet rules, checked against the sourceenPet-friendly airlines compared: fees, carriers and rules in 2026https://www.underseatpets.com/guides/pet-friendly-airlines/https://www.underseatpets.com/guides/pet-friendly-airlines/We scored 15 airlines on seven published pet rules: fees, carrier size, weight caps, pets per person, hold and routes. See which fits your dog or cat.AirlinesSat, 10 Oct 2026 12:00:00 GMTCan dogs fly on planes? How flying with a dog works in 2026https://www.underseatpets.com/guides/can-dogs-fly-on-planes/https://www.underseatpets.com/guides/can-dogs-fly-on-planes/Yes, if your dog fits under the seat. The three ways dogs fly, which airlines allow dogs in the cabin, what it costs, and a step-by-step booking checklist.DogsSat, 10 Oct 2026 12:00:00 GMTAirline-approved pet carriers: what the label means and which sizes fithttps://www.underseatpets.com/guides/airline-approved-pet-carrier-guide/https://www.underseatpets.com/guides/airline-approved-pet-carrier-guide/No official 'airline approved' or 'TSA approved' pet carrier exists. The real under-seat limits for 15 airlines and the sizes that fit most flights.Carriers & cratesSat, 10 Oct 2026 12:00:00 GMTHow much does it cost to fly with a dog? Every airline's pet feehttps://www.underseatpets.com/guides/cost-to-fly-with-a-dog/https://www.underseatpets.com/guides/cost-to-fly-with-a-dog/Cabin pet fees run $100 to $150 each way on most US airlines. Every airline's pet ticket price, hold and cargo fees, health certificate costs and charters.DogsSat, 10 Oct 2026 12:00:00 GMTHow to fly with a cat: airlines, fees and a calm travel dayhttps://www.underseatpets.com/guides/how-to-fly-with-a-cat/https://www.underseatpets.com/guides/how-to-fly-with-a-cat/Which airlines take cats in the cabin, what it costs, how to get a cat through airport security, and how to keep the day calm. Fees checked.CatsSat, 10 Oct 2026 12:00:00 GMTService dogs on planes: DOT rules, forms and the registry mythhttps://www.underseatpets.com/guides/service-dogs-on-planes/https://www.underseatpets.com/guides/service-dogs-on-planes/There's no official US service dog registry. How flying with a service dog works under DOT rules: the forms, the 48-hour deadline, fees, seating and TSA.Rules & documentsSat, 10 Oct 2026 12:00:00 GMTHow big can a dog be to fly in the cabin? Weight and size limitshttps://www.underseatpets.com/guides/how-big-can-a-dog-be-to-fly-in-cabin/https://www.underseatpets.com/guides/how-big-can-a-dog-be-to-fly-in-cabin/US airlines have no cabin weight limit, only carrier size. Europe caps pet plus carrier at 8 kg. How to measure your dog and what to do if it's too big.DogsSat, 10 Oct 2026 12:00:00 GMTDog crate size for air travel: how to measure using IATA's formulahttps://www.underseatpets.com/guides/dog-crate-size-for-air-travel/https://www.underseatpets.com/guides/dog-crate-size-for-air-travel/How to measure your dog for an airline crate with IATA's formula, common crate sizes, and the door, bolt and ventilation rules airlines check.Carriers & cratesSat, 10 Oct 2026 12:00:00 GMTFlying a pet in cargo in 2026: which airlines still do ithttps://www.underseatpets.com/guides/flying-pets-in-cargo/https://www.underseatpets.com/guides/flying-pets-in-cargo/United, Delta and American no longer fly pets in the hold except for military moves. Who still does, what it costs, and temperature and breed rules.AirlinesSat, 10 Oct 2026 12:00:00 GMTAirlines that allow large dogs in the cabin (and what to do if yours is too big)https://www.underseatpets.com/guides/airlines-that-allow-large-dogs-in-cabin/https://www.underseatpets.com/guides/airlines-that-allow-large-dogs-in-cabin/No major US airline lets a large pet dog ride in the cabin. ITA Airways now does on some flights, and BARK Air and K9 Jets fill the gap.DogsSat, 10 Oct 2026 12:00:00 GMTSnub-nosed dogs and cats on planes: which airlines will fly themhttps://www.underseatpets.com/guides/snub-nosed-dog-breeds-airlines/https://www.underseatpets.com/guides/snub-nosed-dog-breeds-airlines/French bulldogs, pugs and Persians are banned from the hold on most airlines. Airline-by-airline rules and why the cabin is usually the only option.AirlinesSat, 10 Oct 2026 12:00:00 GMTBringing a dog into the US: CDC rules and the dog import formhttps://www.underseatpets.com/guides/bringing-a-dog-into-the-us/https://www.underseatpets.com/guides/bringing-a-dog-into-the-us/CDC rules for bringing a dog into the US: 6-month minimum age, microchip, CDC Dog Import Form, high-risk country rules and approved airports. Cats too.Rules & documentsSat, 10 Oct 2026 12:00:00 GMTPet health certificates for travel: CVIs, USDA endorsement and timinghttps://www.underseatpets.com/guides/pet-health-certificate-for-travel/https://www.underseatpets.com/guides/pet-health-certificate-for-travel/What a pet health certificate for travel is, when you need a CVI or USDA-endorsed certificate, how long it's valid and which airlines require one.Rules & documentsSat, 10 Oct 2026 12:00:00 GMTBringing a dog to Hawaii: quarantine rules, fees and airlineshttps://www.underseatpets.com/guides/bringing-a-dog-to-hawaii/https://www.underseatpets.com/guides/bringing-a-dog-to-hawaii/How to bring a dog to Hawaii without quarantine: microchip, two rabies shots, FAVN test, 30-day wait, $185 airport release and which airlines fly pets.Rules & documentsSat, 10 Oct 2026 12:00:00 GMTPet passports: how they work, and what to use if you're in the US or UKhttps://www.underseatpets.com/guides/pet-passport/https://www.underseatpets.com/guides/pet-passport/EU pet passports come only from EU vets. The US has no pet passport, so US pets need an APHIS-endorsed EU health certificate. UK post-Brexit rules included.Rules & documentsSat, 10 Oct 2026 12:00:00 GMTTraveling to Canada with a dog: border rules and the trip homehttps://www.underseatpets.com/guides/traveling-to-canada-with-a-dog/https://www.underseatpets.com/guides/traveling-to-canada-with-a-dog/Taking a dog to Canada from the US: rabies certificate rules by age, when you need a health certificate, Air Canada and WestJet fees, and the CDC return.Rules & documentsSat, 10 Oct 2026 12:00:00 GMTEmotional support animals on planes: what changed and how to fly nowhttps://www.underseatpets.com/guides/emotional-support-animals-on-planes/https://www.underseatpets.com/guides/emotional-support-animals-on-planes/US airlines stopped accepting emotional support animals in 2021. Your ESA dog can still fly as a pet. Airline policies, fees and options for larger dogs.Rules & documentsSat, 10 Oct 2026 12:00:00 GMTFlying with a puppy: minimum ages by airline and countryhttps://www.underseatpets.com/guides/flying-with-a-puppy/https://www.underseatpets.com/guides/flying-with-a-puppy/Most US airlines fly puppies from 8 weeks, but the US needs dogs to be 6 months to enter and the EU about 15 weeks. Minimum ages by airline, cost and tips.DogsSat, 10 Oct 2026 12:00:00 GMTCan you bring a dog on a train? Amtrak, VIA Rail and Europehttps://www.underseatpets.com/guides/dogs-on-trains/https://www.underseatpets.com/guides/dogs-on-trains/Amtrak takes dogs up to 20 lb with carrier on trips up to 7 hours. VIA Rail, UK, Eurostar, German and French train rules for small and large dogs compared.DogsSat, 10 Oct 2026 12:00:00 GMTRoad trip with a cat: carriers, litter, food stops and hotelshttps://www.underseatpets.com/guides/road-trip-with-a-cat/https://www.underseatpets.com/guides/road-trip-with-a-cat/How to drive long distance with a cat: securing the carrier, a travel litter box, feeding, hot-car risks, cat-friendly hotels and ID, from vet guidance.CatsSat, 10 Oct 2026 12:00:00 GMT