August 2019

Audience: Executive Leadership, Foster Caregivers, Public, Shelter/Rescue Staff & Volunteers, Veterinary Team

If your cat is urinating or defecating outside the litter box, we certainly understand your frustration. Luckily, this is a treatable condition in most cases. A medical exam, as well as a few simple changes can help to re-establish proper litter box use.

The first step includes taking your cat to your veterinarian. Whenever a cat suddenly eliminates outside of the litter box, it's strongly advised to get a physical exam including urine analysis and in some cases blood work in order to rule out any illness or injury that may be causing the behavior. Once a medical reason for the lapse in litter box use has been ruled out, you want to consider behavioral reasons.

There are two main behavioral reasons for failure to eliminate in an established litter box. One is marking, which is a form of communication. The second one is inappropriate elimination, which is a toileting behavior. Both behaviors may occur for a variety of reasons.

Answer the following 4 questions:

  • Is your cat depositing urine on vertical or horizontal surfaces?
  • Are you finding large or small amounts of urine?
  • Is your cat still using the litter box or has litter box use decreased?
  • Does your cat stand or squat when she is urinating outside the litter box?

Your cat may display inappropriate elimination if you answered:

  • Larger amounts of urine or feces on horizontal surfaces, while squatting, and reduced or no litter box use.

It is important to keep your cat's litter box tidy and appealing. Cats are picky and if the litter box is not just as your cat likes it, or where your cat likes it to be, then any clothes you may have strewn either on the ground or inside a laundry basket may become the perfect litter box alternative.

Once medical reasons have been ruled out, review the following guidelines to help identify the issue:

  • Are there enough litter boxes? The magic number is one litter box per cat in the household, plus one extra-these litter boxes should be in different rooms to count as separate litter boxes. Two litter boxes are important in one-cat households because many cats prefer to urinate in one location and defecate in another.
  • Offer different types of litter to find your cat's preferred litter: Clumping, non-clumping, sand, clay, etc. If your cat is using soft surfaces such as laundry, chances are your litter is too coarse or too shallow. Use a fine granulated type of litter so the surface is soft and deep, similar to laundry.
  • Type of litter box: Many cats dislike covered litter boxes, especially in multi-cat households, as the cover on the litter box limits the cat's ability to protect herself from being ambushed by other cats. Also, many commercially available litter boxes are simply too small for an average-sized cat, let alone a large cat. The litter box should be at least 1.5 times the length and width of your cat. If your cat is too large for "jumbo" litter boxes available at pet stores (and many, if not most, are), many people are successful using a large plastic storage bin with a "door" cut into it or under-the-bed storage bins, which have lower sides and may not need to be cut.
  • Use of litter box liners, harsh detergents, and scented litters: Cats tend to avoid plastic liners, which catch their claws when they scratch and make unpleasant (to a cat) crinkling sounds. The use of harsh or strong smelling cleaners to clean the litter box may repel your cat, whose nose is much more sensitive than yours.
  • Depth of litter: Most cats prefer to have several inches of litter to dig around in, but some prefer shallower litter. Experiment to find your cat's preference.
  • Trauma associated with the litter box: Has your cat ever experienced painful urination or defecation or other traumatic event associated with the litter box? Do you have dogs or children in your home who might bother the cat when she is trying to use the litter box?
  • Always keep the litter box clean-the litter box might be dirty and the laundry basket may be the only "clean alternative," so be sure to scoop daily.
  • Use mild dishwashing liquid to wash the litter box weekly.
  • Location: Place the litter box in the same room your cat is eliminating outside the litter box.
  • Keep litter boxes away from food and water bowls, as well as the washer and dryer.
  • If you have a multi-story house, have litter boxes on each level.
  • The lingering scent of previous accidents: Once your cat has had an accident, it's important to clean the soiled area thoroughly with an enzymatic cleaner meant for urine, such as Nature's Miracle or Anti-Icky Poo (available at the SF SPCA, at most pet stores, or online). Strong citrus scents tend to repel cats, so scented detergent may be helpful as a deterrent.
  • You might also try Cat Attract, a litter additive available in many pet stores and also available here at the SF SPCA pharmacy. Every cat is different, of course, but we have seen great success with using Cat Attract.


  • Always begin by consulting your veterinarian to rule out medical causes.
  • Check all the above guidelines as every cat and situation is different.
  • VERY IMPORTANT: Do not punish your cat for marking as this will not solve the problem; this can make your cat even more anxious.

This document created by the San Francisco SPCA with a grant from Maddie's Fund®