Southwest Airlines does not require a health certificate or any other documentation from a veterinarian for pets to travel.
Unless a pet is proven in advance as an emotional support animal or clearly a service animal for the blind or handicapped, weight and size restrictions apply to pets brought onto airplanes. Southwest Airlines doesn’t publish weight restrictions, but the cat or dog must fit in an approved pet carrier in which the animal can comfortably move around; the carrier also must fit underneath an airplane seat. American Airlines requires that the carrier be no more than 19 inches in length, 13 inches in width and nine inches in height; also, the pet and its carrier can weigh no more than 20 pounds total.
Unless your pet is a proven service animal, you must pay fees on virtually all airlines to take your pet onboard or check it as cargo. As of 2010, most airlines charged less than $100 per flight direction for pet travel. Also, round-trip tickets will normally include two pet fees. Airlines such as Southwest and Continental limit the number of pets who can fly onboard, so always make advance arrangements with your chosen air carrier.
Southwest Airlines boosting fee to fly pets - USA Today
traveling with very small pets - The Southwest Airlines Community
While Southwest Airlines does not transport pets via our air cargo service, we do accept small vaccinated domestic cats and dogs when traveling with a Passenger in the cabin. Learn more about Southwest Airlines . While Southwest Airlines does not transport pets via our air cargo service, we do accept small vaccinated domestic cats and dogs when traveling with a Passenger in the cabin. Learn more about Southwest Airlines . Unlike some airlines, Southwest does not allow pets as checked luggage. If you wish to travel on Southwest with a pet, you must take it in the airplane's cabin with you. Southwest requires that you house your pet in a pet carrier large enough to completely enclose the animal. Pet owners must pay a fee of $75 each way, as of publication, to travel with an animal. If you don't have a pet carrier, the airline sells approved carriers for $45. Pets must be vaccinated, although Southwest doesn't require the owner to show proof of vaccination.I called them today & Southwest does NOT need any health certificates (unlike other airlines it seems? does anyone know for sure?) Also, as long as carrier fits under seat it matters not the carrier type. Ok, this is too easy vs other airlines. I thought that to fly from AZ to Boston, "she'd need a Rabies update shot in past 12 months", said my vet when asked about this. She says every state has different laws regards pets landing in their states. Yet Southwest claims that is not true nor needed for their air travel.