Northwest Airlines and American Airlines have similar programs, designed for pet safety and comfort during the flight, including connections and layovers. Here's a breakdown of the major airlines' policies and fees. In all cases, arrangements must be made in advance. Southwest Airlines does not accommodate pets. Larger animals must be placed in cargo.
Fees depend on the size of the animal.
Pet must fit under seat in front of you, and be stored in a hard or soft carry case. Cargo fee depends on the size of the dog. You may be asked to show a health certificate from the animal's veterinarian. Pets must be at least eight weeks old. Another option for pet travel is to use a professional animal shipper.