How many household pets you can keep is usually determined by the city in which you live. In most US cities, ordinances often limit the number of dogs to two, and may also limit the number of cats. Other pets like rats, rabbits, guinea pigs, birds, or hamsters may also have a number limit in your area.
The best way to find out if you currently exceed the appropriate number of household pets is to call the local Animal Control department. This can help you determine if you should find homes for some of your pets, or may help you decide whether you can add more. Of course, another factor is not only the number of animals you keep, but also your ability to give them appropriate care. You should definitely have the means to provide adequate food and housing, and be able to pay for veterinary care for any of the pets you own.
Sometimes, laws regarding pets exclude unincorporated areas of a city. This means that, normally, areas outside city limits or rural areas are less likely to place restrictions on the number of household pets you can keep. Again, you still must be able to care for these animals in an appropriate and safe manner.
Even with laws giving you rights to own a certain number of pets, animals that become a nuisance to other neighbors, like constantly barking dogs, can restrict your ownership rights. People have successfully sued neighbors and had pets removed from homes because the animal’s behavior was disturbing another owner’s right to enjoy his property. If you do have a dog that barks frequently, consider animal training or keep your pets indoors as much as possible to minimize the annoyance to neighbors.
What you define as a household pet may not actually be considered one by state or city laws. For example, if you keep snakes, ferrets, or imported animals, they may be considered exotic animals. You should check laws before you get such a pet, and be prepared to apply for a permit to keep an exotic animal. A wolf/dog cross usually also requires a special permit and registration if the dog is at least 50% wolf since, technically, a wolf is a wild animal.
Another category of animals that may not be considered as household pets is small farm animals. No matter how much you love your pot-bellied pig or miniature horse, it may still be considered a farm animal and not a pet. In urban and suburban settings, people may be restricted as to which “farm animals” they can own and may need extra land or special permits to keep these animals.