Cat very suddenly does not want to use litter box...
I've had my fixed male cat Neville for about four and a half years, since he was a kitten. Until about two weeks ago, I've never had a problem with him not using the litter box. He still poops in it, but he has started peeing right in front of it. I haven't found any other places in the house he has gone, just there.
Another cat, a spayed female, joined us at the end of May and they adjusted well. I really want to nip this in the bud, as Neville is a great cat but I can't have a pee'er living in a rented apartment
Leap, and the net will appear - A Salty Piece of Land, Jimmy Buffett
Have you had him tested for a urinary tract infection and/or bladder stones or crystals? IME, the vast majority of cats who pee outside the litter box do so because of a medical issue. Most of the time, a trip to the vet and the correct antibiotic will clear it up. If he does have a UTI and treatment doesn't stop the behavior, you may have to go another round of antibiotics to get rid of it. It took about five months and three separate rounds of antibiotics (as well as a surgery to unblock him) to get rid of a UTI in my cat. But the ONLY time he ever peed outside the box was when he had that going on. As soon as it was gone, he was right back to the box.
Physically- How fit is Neville? Some chunky male cats (not naming names [BUSTER AND MENO!]) seem prone to missing when ... urinating. I solved this by using a converted rubbermaid storage tub as a litter box, having cut a just chunky-cat-sized door in one long side.
Biologically, you want to watch neutered males for crystals in the urethra/bladder, which can start as litterbox missing for urine, progressing to lethargy and blood in urine, and can be fatal. Its also easy to miss in multiple cat households.
And behaviorally, the rule of thumb is number of cats in home + 1 = the number of litter boxes you need. Not just because some cats are fastidious, but because some cats (again, not naming names [BUSTER AND MENO!]) will resource / territory guard a box from their housemates [LADY AND MING], and not share nicely. Then again, I don't let anyone sit on the toilet whilst I'm on it either.
-Buster Kitten as He Who Cannot be Moved
-Me No Like This Pink Sh!T as The Crystalizyer
-Lady Deathstrike as Least Suitably Named
-Ming The Merciless as Formerly Homeless Waif Now Chubby like Babushka
Do not take anything to heart. Do not hanker after signs of progress. Founder of theRiders with Fibromyalgia clique.