Don’t be fooled: Even though your cat has been domesticated, at his core, he is as wild as any of his wildcat cousins. If you asked your cat he might say that he’d be happy to divide his time between living on his own outside and living with you inside. No matter how badly you try, there is no way for you to provide as stimulating an environment as the outdoors. Letting your cat live outdoors, even part of the time, cuts down on maintenance (no litter!) but presents a whole host of other problems.
The two biggest reasons to keep your cat indoors are for disease prevention and a cat’s life span. Outdoor cats are at increased risk for rabies, feline leukemia, fleas and other diseases. With proper vaccinations and medications, you can prevent (or manage) these hazards. Outdoor cats frequently get into fights with other cats. These injuries (depending on the severity) can be easily managed and treated, but it will cost you money each time. Every time your cat gets into a fight, he must go to the vet to be checked out. If any bite becomes infected, you will have a major crisis on your hands.
The life span of an indoor cat ranges from 12 to 20 years. The life span of a feral cat is only 3 to 4 years! An outdoor cat is at increased risk of getting hit by a car and these injuries are usually always severe or worse, fatal.
There are numerous ways to let your indoor cat experience the outdoors without turning him loose on the neighborhood. You can train your cat to walk on a harness or leash. (Note that the younger your cat is when you start training him, the better and faster he’ll learn to accept it.) You can also build your cat an enclosed pen; this way your cat can experience all the outdoors has to offer but he cannot run off anywhere. If your backyard is fully fenced so your cat can’t get around to the side of your house or to the front yard, you can always let him out into his enclosed backyard. There’s always the option of letting him experience the outdoors from his carrier or crate.