You’re heading out of town and would love your cat or dog to join you. Is it a bad idea to let your pet fly?

The Humane Society of the United States recommend that you don’t travel by plane with your pet unless there’s no other option. The flight can be stressful and even dangerous for an animal. In 2011, 35 pets died while flying on airplanes. In some cases, the cargo holds became too hot or too cold during the flight or while the plane sat on the tarmac awaiting a signal for takeoff. In others, the stress of the flight made a pre-existing health condition worse. 

Air travel for pets can also be expensive. American Airlines, Delta and United, for example, all charge $125 for pets each way if they fly in cabin. The charge can be $200 or more if pets fly as cargo.

But sometimes driving isn’t an option. Here are ways to make air travel safer for your pet when you just can’t leave him at home.

Some basic rules

The federal Animal Welfare Act (enforced by the Animal and Plant Health Inspection Service of the U.S. Department of Agriculture) outlines important requirements for pet airline travel. They include: 

  • Dogs and cats must be at least 8 weeks old and must have been weaned for at least 5 days in order to fly on an airplane.
  • Your crate must meet regulations set by the International Air Transport Association. These call for adequate ventilation, a waterproof bottom, a spring-locked door, disabled wheels and no handles (except for smaller crates). Your pet should be able to stand up and turn around comfortably in the kennel.
  • Don’t bring your pet to the airport more than four hours before your plane is set to take off.

In addition, each airline may have its own set of regulations.

Depending on your pet’s size, you may be able to choose whether he rides with you in the cabin or in the cargo hold. But no matter where he sits, follow these tips:

  • See your vet several weeks before you travel. Most airlines require proof of immunizations or good health. Plus, you want to make sure your dog is healthy so stress or illness doesn’t affect her trip.
  • Don’t sedate your pet unless your vet strongly recommends it. Tranquilizers can affect your pet’s breathing.
  • Make sure your pet is used to his crate. If not, he could be stressed during the journey.

Flying in the cabin

If your pet is small, you have the option of keeping him with you in the cabin. He must be small enough to fit in a crate under an airline seat. In addition, some airlines have weight restrictions. This is often the least stressful option for you and your pet because you’re together. Some things to consider: 

  • The airline may require a specific type of carrier. Call ahead to make sure yours fits the requirements.
  • There are limits to the number of pets that can be on any given flight. Make your reservation early.

The cargo hold

The U.S. Department of Transportation says pets must be kept in pressurized cargo holds that are temperature-controlled, just like the main cabin. Some other tips: 

  • Choose a direct flight if possible and always travel on the same flight as your pet so he won’t be waiting somewhere without you.
  • Don’t feed your pet for 4 to 6 hours before the trip. The unfamiliar surroundings and movement of the plane might upset her stomach. Give only small amounts of water, and put a couple of ice cubes in her crate at the last minute.
  • Carry a current photograph of your furry friend in case he’s lost during the trip.

Dogs with pushed-in faces

Unlike dogs with regular-length snouts, dogs with short noses — including pugs, Boston Terriers, boxers, some mastiffs, Pekingese, Lhasa Apsos, Shih Tzus and bulldogs — are prone to respiratory problems because they don’t breathe as efficiently, according to the American Veterinary Medical Association. That’s why changes in air quality and temperature in the cargo hold of the plane affect short-nosed breeds more. (Some short-nosed cat breeds may also be affected, but most cats fly in the cabin, where there are fewer problems.)

If you must fly with one of these breeds, take some extra precautions for your pet’s health:

  • Schedule your flight with no layovers, if possible. If you’re flying in summer, fly early in the morning or late in the day. Plane temperatures aren’t as comfortable when the plane sits on the tarmac — especially in hot weather.
  • If your dog is small enough, consider bringing him in the cabin with you.
  • Check with your airline to make sure it allows snub-nosed breeds to ride as cargo. Some don’t.