Common Causes and What You Can Do About It When your cat starts peeing outside the litter box, it’s frustrating. It’s stressful. And it can feel personal. Inappropriate urination in cats is one of the most common behavioural concerns pet owners face, and it’s almost always a sign that something needs attention. You might find yourself asking: Why is my cat suddenly not using the litter box? Are they mad at me? Is this behavioural? Here’s the important thing to know: Cats do n