If One of My Cats Is Urinating Outside The Box, Will My Other Cats Urinate Outside the Box Too?
There are many reasons why some cats won't use the litter box. Owners are often worried whether other cats will urinate outside the litter box once one starts.
The cause of inappropriate urination can either be behavioral or medical. Urinary infections, inflammatory diseases or even bladder stones can cause cats to avoid the litter box. Other cats will avoid the litter box for reasons like the litter box is too dirty, they don't like the litter, the location is noisy or another cat is preventing them access to that box.
Owners with more than one cat often want to know: if one cat urinates outside the litter box, will others start to do it too?
The answer is no--mostly. Urinary problems are not contagious from cat to cat, so your cat won't get kidney stones from using the same litter box as a sick cat or begin peeing outside the box after watching them. However, some inappropriate urination is due to territorial urine marking and this can influence another cat's behavior. If a cat smells where another cat has urinated outside of the box and feels like their territory is threatened, they can be tempted to mark over it. That is why it is SO important that you properly clean up all urine accidents.
For more information on how to really clean up urine accidents, please read:
Cat Urine Odor Removal - Vet's Advice On Cat Urine Odor Removal
Why Cat Urine Odor Comes Back & How to Stop It
I hope this gives you more information on whether inappropriate urination is contagious between cats.