Why does my cat lift her backside to urinate outside the litterbox?

Q: I'm going crazy here! My 7-year-old spayed female cat is really well-behaved, and we've had no behavior problems ... until now.

Recently, when she uses her litterbox, she turns her butt toward the side of the litterbox, and as she urinates, she slowly raises her butt until the urine is trickling over the side. This doesn't happen when she faces a different direction. The problem occurs about 50 percent of the times she uses the litterbox. Still, she has never "missed" the litterbox, nor has she ever urinated outside the box.

Nothing has changed. The litterbox is the same. We use a popular automatic litterbox which keeps it very clean and have used this box since she was a kitten. The brand of litter has never changed, nor has the location of the litterbox. She has recently seen the vet for her twice-yearly checkup, and she was given a clean bill of health.

Is there anything I can do? So far, whenever I see her in the "bad" position, I go to the litterbox and gently hold my hand over her rear end to prevent her from raising her butt to the height where she'll drip over the edge of the box, at the same time saying, "Butt down." I don't raise my voice, and I never have punished her for this behavior, as I don't want to discourage her from using the litterbox at all.

A: You are not alone. I have other clients with similar challenges that have bought automatic litterboxes for their cats. Some of these kitties back their butts over the side of their litterboxes and then defecate; others either stand and urinate or squat over the side. These undesired bathroom calisthenics defeat the purpose of buying an automatic litterbox. 

Most automatic litterboxes are too small for a lot of cats. Cats like large litterboxes that they can circumnavigate easily. Additionally, automatic litterboxes can be hard to clean. Often the excrement becomes caught in the moving parts. From personal experience, I know that cleaning the parts can be a very time consuming and unrewarding chore. When cats do miss and urinate over the side, it’s important to clean the targeted area outside the litterbox thoroughly with a good enzyme cleaner. Otherwise, the cat will smell it and may continue to target the same areas.

I have found that the best box for the job is not a traditional cat box. I recommend 66-quart, uncovered Sterlite ClearView storage containers. They are large storage boxes with high, translucent sides that will accommodate even the plus size cat. Your kitty can stand up and urinate as much as she wants, and it will stay in the box. Also, cats who like to dig in their litterboxes can dig until their hearts’ content and the litter stays in the litterbox. A couple of other advantages to these storage containers are that cats can see through the box, and since the boxes aren’t covered, they don’t retain odors. These storage containers can be modified for cats with arthritis or other special needs by cutting and then sanding a “U” shape into the narrow side. (Make sure to wear a safety mask when cutting or sanding plastic.)

I know that scooping litterboxes is not a chore most people look forward to doing. In the long run, you probably will find it’s easier to scoop every day than to thoroughly clean around and under a cat litterbox that is too small.