How do I litter train an adult cat?
Quick answer
Litter training an adult cat is less about teaching a new skill and more about removing the reasons she avoids the box, so expect it to take weeks rather than days and plan for patience.
The full answer
An adult cat that was never reliably trained — a former stray, a cat kept outdoors, or one from a shelter or hoarding situation — may have no habit to build on. A cat that once used a box perfectly and stopped has a reason you have to find before anything else will work.
Why adult cats are harder to train than kittens
Kittens explore new objects out of curiosity, which is why they often walk into a litter tray by accident. Adults do the opposite and avoid anything unfamiliar, so a new box or a new litter can send a cat straight to the carpet.
Adults also have firm preferences about litter texture and box type, and one frightening experience can undo weeks of progress. They are far less forgiving than kittens about a box that is small, dirty, covered or in a busy spot.
Setting up the room and the boxes
Start by confining the cat to a small, quiet room with the box in a corner that leaves an escape route. Offer two boxes near each other — one with the litter she already knows and one with a fine, unscented clumping litter — so she can choose instead of being forced to switch.
Bigger is better. A box about one and a half times the cat's body length, with low sides and no lid, suits most cats. The usual guideline is one box per cat plus one extra, placed in different locations rather than lined up together.
Changing boxes or litter without losing progress
If you must change the setup, keep the old one available and transition gradually. Mix a little new litter into the old, or leave the new box beside the old one for a week before removing the old box.
Skip liners, deodorisers, hoods and scented litters while the habit is being built. These are common reasons a cat decides the tray is unpleasant, and they add no benefit for the cat.
Building the habit with routine and reward
Feed on a schedule, and set the cat gently in the box after meals and after waking, when cats most often need to go. Reward any interest at all — sniffing, stepping in, digging — with praise or a treat, and never punish an accident.
Scoop at least once a day and change the litter regularly. A box that is always clean is the most powerful training tool you have, because the cat simply prefers it to the alternative.
Cleaning up accidents the right way
Clean soiled spots with an enzymatic cleaner and avoid ammonia-based products, because ammonia smells like urine and can draw the cat back to the same place.
Make the old spot less appealing: place a litter tray or a low obstacle over it temporarily, or move a food bowl nearby, since most cats avoid eliminating where they eat. Blocking access to the spot without offering a better option usually just moves the problem.
When the problem is medical rather than behavioural
If a previously reliable adult cat starts eliminating outside the box, see a vet first. Urinary infections, crystals, kidney disease, diabetes and arthritis pain are all common in adult and senior cats, and a cat in discomfort may associate the box with pain.
Stress can trigger avoidance too: a move, a new pet, a new baby, building work or a changed routine. So can practical issues such as a box that is cleaned less often, a new litter, or another cat guarding the tray. Work through the list before assuming the cat is being difficult.