Dear Most Esteemed and Knowledgeable Kitties:
My cat is female almost 15 years old. Recently when she uses the litter box, pee goes over the side. More comes out of the box than stays in. I bought a new box with 8-inch-high sides and still have the same problem. The litter is clean and she gets in it.
~ Reda
Thomas: First of all, Reda, thank you for caring so much about your elder kitty’s health and well-being! I’m going to be 15 this year, too.
Bella: One of the things that happens a lot in older cats is that they develop arthritis in their hips and knees. This makes it less comfortable to assume the proper positions for peeing and pooping.
Tara: And when a cat is uncomfortable, it often results in litter box accidents.
Thomas: So the first thing we’d recommend is a trip to the vet to see if your beloved kitty does have arthritis. If she does, there are ways to manage the pain so she can enjoy a good quality of life.
Bella: And there actually litter boxes with even higher sides!
Tara: That’s right. My litter box has 11-inch-high sides, on three sides and the back.
Thomas: We’ve got another one of those 11-inch-sided litter boxes plus an even bigger one with 10-inch-high sides.

Bella: Another thing you can do is create a litter box from a storage tote, which would have really high sides.
Thomas: Here are some instructions for how to make that storage-tote litter box.
Bella: We’d recommend a clear storage container instead of a solid-colored one, because we like to be able to see around us a little bit.
Thomas: We probably also wouldn’t put a lid on it, because we don’t think covered litter boxes are a very good idea.
Bella: Covered litter boxes tend to trap odors (yuck!) and hide the evidence of our biological functions …
Tara: … which can cause people not to clean the litter box as often as they should.
Thomas: And that’s just nasty for everyone.
Bella: So, Reda, like we said, the first thing we’d recommend is that you take your kitty to the vet to see if she’s in pain.
Tara: And then get or make a litter box with even higher sides so it’s impossible for her to pee over the edges!
Thomas: We hope this helps!
Bella: What about you other readers? Do you have tips for Reda on how to manage her kitty’s over-the-side-of-the-box urination? What’s worked for you? Equally important, what hasn’t worked for you?
Tara: Please share your thoughts and experiences in the comments.
my guys can be a little messy at times too. But I would be worried about getting a higher sided litter box if your guys are arthritic – it might be more problematic for them getting in and out. my solution was a tote about the same height as a normal litter box and cutting the lid leaving about 2 inches around the edge. It makes my guys get more into the centre.
My sweet Evie in the last year of her life was so upset about the fact that most of her pee went outside the box that she started standing on the outside and sitting on the edge so all her pee went inside the box. She was a very smart kitty and was much happier when she figured that out.
I have a “vertical” pee-er, she has never squatted to pee, she just stands and pees and her brother was the same way (I just lost him in Oct from a tumor at the base of his spine, so maybe why he never squatted). Anyway, it made things challenging, but I finally came up with a solution that works. I lay down several puppy pads, have a high-sided kitty litter as a normal litter, and I put a regular litter pan vertically behind that so the pee doesn’t hit the walls, it just drips from the litter pan onto the puppy pad. It makes clean up SO much easier.
June Dolan had a great idea! I have three cats. One male and two female. All are older. My male is 18 and has CKD and arthritis so he was very messy in the box.
I had gotten a couple of NevrMiss boxes with high sides on three sides that were supposed to orient the cat, but all of them very seldom used them. And not the way they were intended!
I got some more at PetSmart that actually had a much lower opening that they all love!
You can’t put a whole lot of litter in them. Just a couple of inches or if you have a kicker like my youngest, it will all be outside the box!
Our Zoey will occasionally pee over the side of the box….and she’s only 8 years old. The mom tried a higher side box, but Zoey wouldn’t use it. She’s strange like that. Maybe the mom needs to try the higher box again.
When I had my Fancy-girl, she came to me after a long time on her own. She had suffered some sort of injury to her back, so her back legs never did work completely right, and her vision and hearing weren’t great either — my sweet Fancy-girl was old. She was probably about 12 or so when she found me, and between the difficulties with her back legs and the arthritis she was starting to really develop, using a litter box was a challenge for her, or so I thought.
Also, she was a large cat – in her prime, would have likely been an easy 20 lbs.
Each of the litter boxes in the house are/were tucked into quiet/private corners, but, even with a large box, Fancy had trouble ‘going’ IN the box, no matter how hard she tried.
I REALLY thought it was from her physical problems – but it WASN’T.
It turned out that she didn’t have enough space around the box for her to center (as cats do, naturally), she could ‘feel’ the walls surrounding the boxes and wouldn’t get all the way in.
The solution was easy, on BOTH of our parts: I turned the boxes so the narrow side was against the wall, and one long side was against the other barrier (wall, cedar chest, etc). This gave her a couple more inches ‘in’ and space along the other long side, above the box.
Fancy’s solution after the switch was to get into the litter box from the front, and then walk her front half OUT of the box and stand in the new open space.
The arthritis/lameness meant she couldn’t squat at all, but she’d flip her tail out of the way and do her thing.
Her litter box habits were fine ever after — even when she began to fall over when she walked… RIP my Fancy — I’m so glad that you spent your last 18 months inside with plenty of food, love and comfort.