By Jennifer Copley (Last Updated 1 September 2011)
Cats may urinate outside the litter box for a number of reasons, including:
- Marking Territory: The cat is claiming an object or area as his own. This is a common problem in multicat households.
- Fear: The cat has been frightened while using the litter box or near the spot where he has urinated.
- Litter Box Problems: These may include location, type of litter, and other issues.
- Stress: Changes that cats find traumatic such as moving house can cause soiling outside the box.
- Illness: Inappropriate elimination is a symptom of many different medical problems. If a cat begins urinating outside the box, take him for a veterinary check-up to rule out health issues before assuming that it’s a behavioural problem.
It’s important to clean cat urine thoroughly as soon as it’s discovered, or the scent will lure the cat back, encouraging him to keep marking the same spot. Other cats, vying for territory within a multicat household, may also urinate on a spot that the first cat has marked to assert their own claims.
How to Remove Fresh Cat Urine from Carpets or Furniture
Fresh cat urine is acidic, while dried urine is alkaline, so different cleaning strategies are required for each. Vinegar, often recommended for cleaning cat urine, will affect the pH of fresh urine in a way that makes the odour difficult to permanently eliminate. When fresh urine has been cleaned with vinegar, the smell can be brought back to life on humid days.
To clean fresh cat urine from carpeting or upholstery so that the odour is permanently removed, use the following strategy:
- Step 1: Blot the area with dry rags or paper towels – don’t rub, as this may force urine deeper into the fabric or carpet underlay. Press down on the rags or towels to soak up as much urine as possible.
- Step 2: Saturate the area with a dish detergent solution (1 teaspoon of mild dish detergent to 1 quart of warm water). Let the solution sit for an hour or two if possible. Then rinse the area thoroughly (a wet sponge can be used for this purpose) and allow it to dry.
- Step 3: Apply an enzymatic cleaner such as Nature’s Miracle to ensure that all scents detectable to cats have been eliminated (enzymatic cleaners should also be used for cat urine on hardwood or concrete). More than one application may be required.
- Step 4: If the cat has urinated on a carpet, it may have soaked through to the underlay or even the floorboards underneath. If possible, pull up the carpet and clean the area underneath the urine spot. Allow the area to dry thoroughly before replacing the carpet. The padding inside furniture that has been targeted may also require cleaning.
How to Remove Dried Cat Urine from Carpets or Furniture
Dried cat urine, which may be hidden away in closets and other out-of-the-way spots, can be found using a black light (black-light-equipped portable flashlights are available at many hardware and pet supply stores). To clean dried cat urine:
- Step 1: Soak the area with a vinegar and water solution (2 parts water to 1 part vinegar). Allow the mixture to sit for a few minutes and then blot with dry rags or paper towels.
- Step 2: Follow steps 2-4 for cleaning fresh cat urine (see above).
How to Prevent Cats from Urinating Outside the Litter Box
In addition to thoroughly cleaning and de-scenting the area, there are ways to prevent cats from urinating outside the box, particularly if they are targeting a specific place over and over again. Effective strategies include:
- Blocking access to the area if possible or using carpet runner (pointy side up), tinfoil, or Sticky Paws tape (all items that cats dislike walking on) to cover the spot for a few weeks until the habit is broken
- Avoiding the use of ammonia-based cleaners, as the smell may encourage cats to continue urinating on the spot where it has been applied
- Discarding smaller items (i.e., pillows) that are frequently targeted
- Trying a pheromone product, such as Feliway (some owners find these products useful in reducing or eliminating urine marking)
- Taking steps to reduce conflicts among cats that may contribute to territorial marking
- Addressing any problems with the litter box that cause the cat to avoid it
Scolding or punishing cats for urinating or defecating outside the box is unlikely to stop this behaviour. In fact, it often increases inappropriate elimination because anxious cats are more inclined to go outside the box. Providing extra attention and reassurance is more likely to have a positive effect on undesirable behaviour than punishment.
For more cat articles, see the main Cats page.
- Christensen, Wendy, and the Staff of the Humane Society of the United States. (2002). The Humane Society of the United States Complete Guide to Cat Care. New York: St. Martin’s Press.
- The Ohio State University College of Veterinary Medicine. (2009). “How to Clean up Cat Urine.”