Help! My cat started pooping/peeing outside the litterbox! What should I do?

Try completely (avoid anything with a strong smell) cleaning and refilling the box with the usual litter. The new stuff may have had a smell, or even texture that the cat didn’t like. Some are very particular about their litter. . . .just like the material they prefer to use to scratch on or to sleep on. Most do not like change and can get upset when things are suddenly not to their liking. Good luck!

Agreed; cats are very fussy and one bad experience can lead to a life-long behavioral shift. The important thing to remember here is that you are dealing with an intelligent being with a totally alien thought process.

Since he is now urinating in the box, it seems to me that it was more of a textural thing as it takes a bit of digging to cover up after dropping a deuce whereas a mere spritz may not be worth burying so he doesn’t have to stick his paws into the litter that was so nasty last time he did. It also seems to me that once he figures out that you are using the regular litter again, things will be back to normal, but you might want to clean the box thoroughly as @zzc suggested.

For future reference, cats do not like change that much. Switching cat litters of foods may seem like no big deal to us humans, but can literally traumatize a cat. Even rearranging furniture can cause some issues. This is why my wife and I have occasionally cut back on our food budget for the week to buy the usual brands; it’s easier to borrow lunch money from a co-worker for a couple of days than deal with a cat (or five!) that won’t eat, that pukes all over the place, or just wont use the litter box for weeks.

Lol cats are complicated. its like what @jerv said. for example my cat used to ALWAYS sleep at the food of my bed at night. we changed sheets just for one night cuz mine were being washed, and she didnt like them and didnt sleep at the foot of my bed or on my bed at all. even after we changed back the next day, shes never slept there with me. cats are friggin picky lol. if i were you i wouldnt be asking on this site, and try to find a local animal veterinarian or somebody more experienced with animals/cats to tell you how to solve this. good luck!

There’s only two explanations I can see here. The first being that cats really are that picky, and it will take some time for your cat to eliminate the thought of the new litter out of it’s mind. The second, less likely but more serious reason, is they might have a UTI. Just throwing all possibilities out there, but looks more like the cat is just in a bad mood from having it’s habitat changed.

I agree with @Moegitto, it’s probably the change of the litter. If your cat was doing this, and you hadn’t changed anything, the cat might be trying to tell you something is wrong with him, like a urinary tract infection, and you should head to the vet.

Talk to a vet. I bet they would have the best answers. You never know, it could be some bladder thing.

I have had cats with UTIs and they all used the box (or tried to, or yelled while doing so) without missing, so I doubt that’s it.