One of the main reasons cats get surrendered to shelters is house soiling due to failure to use the litter box. First let’s discuss some preventative steps, and secondly remedies.
To minimize the chance of litter box problems developing consider these simple rules:
There is a difference between urinating or defecating outside the box and marking. Marking tends to be small amounts of urine on a wall or on the floor near a wall, and generally in the same one of two places over and over again. This is sometimes used as a defense mechanism by the cat when he or she feels insecure in the environment. It is more common in males but definitely occurs in females as well.
Urinating outside the box may also occur in the same spot again and again, but it occurs because the cat is drawn back to that spot by the odor. There are many reasons cats urinate or defecate outside the box. If the cat associates the box with something unpleasant, he will start to avoid it. Pain is a big reason. The first thing to do when a cat begins to go outside the box is take it to the vet for a check up. A urinary tract infection or a kidney stone may be the cause. In a multi-cat household, one cat may be harassed at the box and therefore choose to go elsewhere.
If you can discover the cause, than the remedy can be fairly simple. However, most of the time the cause remains a mystery, known only to the feline mind. First, consider everything mentioned above under prevention. Secondly, consider one, all or some of the following options: