You could be to blame if your cat is using something other than its litter box for its bathroom needs. Due to their instincts to hide their waste, most cats will use a litter box without any training, but cats are picky about the type of box they go in and its cleanliness. Choosing the best litter box for your cat will encourage the cat to use the box and nothing else as its bathroom.
The best material for a cat's litter box is plastic. Plastic is easy to clean and won't absorb the odors from your cat's waste. Plastic litter boxes come in a wide variety of colors to match your decor. Because they are durable, plastic boxes can withstand the scratching your cat will do when covering up its waste.
The best litter box is one that is big enough for your cat to fit in. A large cat is likely to "miss" the box if it is trying to go in a box that is too small. Cats also don't like to step in their own waste and a larger box helps them avoid this. The best boxes are at least 24 inches long and 20 inches wide. The sides of your box need to be high enough so your cat doesn't kick litter out. Four inches is the minimum height, but some cats will need sides at least a foot high depending on their potty habits.
Number and Location
The number of litter boxes depends on the number of cats you have and their bathroom habits. Some cats will not go in a box another cat has used so you should have at least as many boxes as you have cats. Even if you have only one cat, it may want to urinate in one litter box and use another one for defecation. If you have more than one cat, the boxes should be in several locations in your home to avoid territorial issues between cats.
Covered or Not
Covered cat boxes come with a dome or rectangular cover that fits over the tray. The advantage of this is the reduction of litter being scattered around when the cat covers up its waste. Some cats also enjoy the sense of privacy. However, a covered box makes it easy for you to forget to clean, can make some cats uncomfortable and holds in fumes and dust your cat has to breathe while inside. A better option for a cat that kicks its litter around is to use a high-sided storage tub and make it into a litter box (keep the lid off the tub); or place the litter box inside the tub.
Self-cleaning litter boxes are an option for the lazy pet owner. Your cat doesn't like a dirty box and if the box isn't cleaned at least daily, the cat may find other places to go. Places that won't make you happy. If you don't want to or can't remember to scoop the litter box each day, a self-cleaning box is a good option if you have the money for it. However, you must have a mellow cat for this type of box because some cats become afraid of the mechanical sound the box makes.