Flying with a dog or cat on Southwest Airlines: small pets can fly in the cabin ($125 each way), and there is no hold or cargo option. Each answer links to Southwest Airlines's own page.
Small, vaccinated domestic cats and dogs can fly in the cabin on domestic flights, at least 8 weeks old. One carrier per ticketed customer, with up to two cats or dogs of the same species in it. Pet reservations cannot be made online — call Southwest.
Source: Southwest — Pet policy
$125 per pet carrier, each way, on the US mainland, and $35 between the Hawaiian Islands. Refundable if you cancel.
Southwest does not carry pets in the cargo compartment — the cabin is the only option.
Source: Southwest — Pet policy
Whatever the airline, the CDC requires every dog entering or returning to the US to be at least 6 months old, microchipped, healthy, and to travel with a CDC Dog Import Form receipt.
The CDC dog import rule, step by step →Airlines change pet fees and rules often, and limits can depend on the aircraft. Always confirm with Southwest Airlines when you book — the linked pages are the final word.
