I am a subscriber to Dr. Jon from PetPlace.com. It is a daily email which is loaded with great information on dogs.
Today he highlighted pet airline travel as it is National Aviation Day. ( Did you know that?) At any rate, the article was loaded with excellent up to date information on the rules and regulations of several different airlines regarding pet travel.
Most airlines, with the exception of Southwest, will let your pet travel in the cabin with you if its carrier is small enough to fit under the seat in front of you. Some airlines, however, limit the number of pets traveling in this manner on any given day, so be sure to book early. The average cost for the pet traveling in the cabin is between $75.00 - $80.00 each way. It is definitely the safest way for a small pet to accompany you by air.
For larger dogs who don't meet this criteria, most airlines have placed an embargo on when pets can travel in cargo. The general rule is, if the ground temperature in the departure or arrival city, or any stops along the way, is above 85 degrees F or below 10 degrees F the pets can't travel in cargo that day. Some airlines have banned pet cargo travel completely between May 15th to September 15th. Due to some tragic incidents, these restrictions have been put in place to protect the pets from possible health dangers. Southwest does not permit pets in cargo at any time..
Alternatives include Pet Airways, which allows all pets to travel in the cabin, or ground transportation. Check out Starwood Animal Transport..
The most important thing to remember is to make your plans early and be sure to check the rules and regulations with whatever airline you are planning to use.