Cat Recently Started Pooping Outside Litter Box

[Outmannedmama]

Kitkat is 5 years old. In the last month or so he has started pooping outside the litter box. We have 1 litter box upstairs and 2 downstairs. We got another cat about 8 months ago but they get along well even if they don't love each other. I switched to a different litter shortly before this behavior started so I switched back to the normal one thinking that was the cause but no such luck. We do scoop them daily and full change every few weeks.

Any ideas to try? Maybe buying a brand new box?

Edit to add: he pees just fine in all 3 boxes.

 

[FeebysOwner]

What is the consistency of Kitkat's poop - softer or harder than normal? The first thing that comes to mind in a cat no older than yours, is constipation or loose stool. Either can cause discomfort and a lot of cats blame the discomfort on the litter box and not their own body.
One of the causes of this could be from a food change, or a cat becoming intolerant to something in their food even if they have eaten it for a while.

Does he use one certain box for pooping outside of it, or is he pooping outside all 3 of them? Is the poop always nearby to the boxes, in other specific places, or randomly anywhere? If in designated spaces, it might be that the first time was a one-off, and now that he can smell his scent outside the box he continues to go there, as well as repeating the habit near the other boxes too. So, clean up with enzymatic cleaners to remove any smell is essential.

Another possibility is that he has decided he does not want to pee and poop in the same box(es). In this case, another (4th) box set up near one of the other boxes might be something to try to see what happens. Will he pee in one of the boxes if there is poop in there from the other cat?

I don't know if anything in this article will help, but it can't hurt to look.
The Litterbox - What Every Cat Owner Needs To Know - TheCatSite

 

[rubysmama]

Not much I can add to FeebysOwner 's post, other than when my Ruby poops outside the litter box, it's generally when things are a bit too hard/dry, or too soft. So maybe a similar situation is going on with Kitkat.

Another litter box could help, especially if you can put it in different location. However, with 2 cats, 3 litter boxes is generally enough.