What is litter box aversion?
Updated By PetymFacts checked against official sources on
Quick answer
Litter box aversion is when a cat stops using its litter tray and pees or poos elsewhere in the home, because something about the tray, its place or its use has become unpleasant or frightening. Illness is a common cause, so a vet check comes first. Then fix the trays: enough of them, clean, quiet, with litter the cat likes.
Also called cat peeing outside the litter box, house soiling in cats, inappropriate elimination, litter tray problems.
Key facts
- Urinary disease, diarrhoea, hyperthyroidism and diabetes can all cause soiling, and a cat that strains or passes only small amounts of urine must be seen urgently. International Cat Care
- International Cat Care recommends one litter tray per cat plus a spare, in quiet spots away from food. International Cat Care
- Use fine, unscented litter at least 3 cm deep, remove solids at least twice a day and clean the tray fully at least weekly. International Cat Care
- Toileting areas should always be away from food and water, and scented litters may disrupt a cat's scent profile. AAFP and ISFM (Journal of Feline Medicine and Surgery, 2013)study
- Soiling is a sign of stress or illness, not revenge, and punishment makes cats fearful and the problem worse. International Cat Care
When is a cat peeing outside the tray an emergency?
Always think medical first. Many cats avoid the tray because toileting hurts.
If Straining in the tray, passing only drops of urine, crying while peeing, or blood in the urine.
A cat trying and failing to pee may have a blocked urethra, more often in males. This is an emergency: see a vet immediately. International Cat Care
If Soiling with diarrhoea, weight loss, more thirst or more urine.
Book a vet visit soon: diarrhoea, diabetes, hyperthyroidism and kidney problems can all cause it. International Cat Care
If An older cat soils near the tray or on soft surfaces.
Ask your vet about arthritis. High-sided trays and stairs to the tray can hurt. International Cat Care
What turns a cat off its litter tray?
Cats are fastidious and feel vulnerable when toileting. Small things matter.
A dirty tray is the most common complaint; cats do not like using soiled litter, and in multi-cat homes they compete for trays. Strong smells put them off too: scented litter, deodorisers and harsh cleaning products. Liners can snag claws. Hard wood pellets can hurt arthritic paws. Some cats prefer covered trays and some open ones, so try both.
Location matters as much. A tray beside the food bowl, next to a noisy washing machine, in a busy corridor, or where another pet or a child can corner the cat, may be abandoned. In Indian flats trays often end up on a balcony or in a utility area, where monsoon rain, heat, firecrackers or neighbourhood cats seen through the grille can make the spot feel unsafe. Moving house, a new pet, building work or guests can also cause stress-related soiling, including feline idiopathic cystitis.
How do you get a cat back to its tray?
- Get a vet check and a urine test first. International Cat Care
- Provide one tray per cat plus one, in different quiet places, away from food, water and beds. International Cat Care
- Scoop at least twice a day and clean the whole tray weekly with mild, unscented products. International Cat Care
- Use fine, unscented, sand-like litter at least 3 cm deep, and offer trays with at least one low side for older cats. International Cat Care
- Clean soiled spots with an enzymatic cleaner made for pet urine, or a 10% biological washing powder solution; never ammonia-based products, which smell like urine. International Cat Care
- Never punish the cat, rub its nose in it or shout; it increases fear and soiling. AAFP and ISFM (Journal of Feline Medicine and Surgery, 2013)study
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Questions owners ask
Why has my cat suddenly started peeing outside the litter box?
- Start with a vet check, because urinary disease, cystitis, diabetes and other illnesses commonly cause it. If the cat is healthy, look at the tray: is it clean, is the litter new or scented, has it moved, or is there a new pet, person or stress at home? Fix the cause rather than punishing the cat.
How many litter trays does a cat need?
- International Cat Care recommends one tray per cat plus a spare, placed in different quiet locations, away from food and water. So a single cat needs two trays, and two cats need three. In multi-cat homes, spread the trays out, as cats can compete over access to them.
Is my cat soiling to get back at me?
- No. Cats do not soil out of spite. Soiling is a sign of illness, pain or stress, or a sign the tray is unpleasant. Punishing the cat makes it more anxious and can make the problem worse. Work out what changed, see your vet, and improve the tray set-up.
What is the best way to clean cat urine?
- Use an enzymatic cleaner made for pet urine, or a 10% solution of biological washing powder, rinse with cold water and let it dry fully. Avoid ammonia-based cleaners, which smell like urine and can draw the cat back. Throw away heavily soiled fabrics where possible.
Keep reading
Related terms
More in behaviour
- Calming signalsCalming signals, also called appeasement or displacement behaviours, are small body-language cues such as lip or nose licking, yawning, turning the head away, blinking, sniffing the ground or lifting a paw. Dogs often show them when they feel uneasy or in conflict. Noticing them lets you give a dog space before fear escalates to growling or snapping.
- Cat scratchingCat scratching is the normal habit of dragging the claws down a surface. Cats scratch to keep their claws healthy, stretch the legs and spine, and leave scent and visible marks from glands in their paws. It should not be stopped, but it can be moved from the sofa to a well-placed, sturdy scratching post with patience and rewards.
- Destructive chewingDestructive chewing is when a dog chews things it should not, such as shoes, furniture, door frames, wires or cushions. Chewing itself is normal: puppies chew to ease teething and all dogs chew to explore. It becomes a problem through boredom, too little exercise, hunger, frustration or separation anxiety, and is fixed by redirection, not punishment.
- KneadingKneading, often called making biscuits, is when a cat rhythmically pushes its front paws into a soft surface such as a blanket, cushion or a person's lap, often purring. It starts in kittenhood, when kittens knead their mother to keep milk flowing, and many adult cats keep the habit when relaxed. It is normal and needs no treatment.
- Noise phobiaNoise phobia is an intense, lasting fear of loud or sudden sounds such as fireworks, thunder or gunshots. Affected dogs tremble, pant, hide, pace, try to escape or soil indoors, and some take days to recover. It is common: about a third of dogs in one large survey were noise-sensitive. A safe den, preparation and gradual training help.
- PicaPica is eating things that are not food, such as fabric, wool, plastic, paper, rubber, stones or soil. In cats it often starts as wool or fabric sucking, especially in Oriental breeds; in dogs it can be a habit, a compulsive disorder or a sign of illness. Swallowed objects can block the gut, so a vet check comes first.
- Reactive dogA reactive dog overreacts to everyday triggers such as other dogs, strangers, bikes or autos, usually by barking, lunging, growling or pulling, most often on the lead. Fear is the most common driver, with frustration and pain also playing a part. It is managed by keeping distance from triggers and changing the dog's feelings with reward-based training, never by punishment.
- Resource guardingResource guarding is a dog protecting something it values, such as food, a chew, a toy, a bed or even a person, from people or other animals. It is normal, often fear-based behaviour, ranging from eating faster or freezing to growling and biting. It improves with management and reward-based training that teaches the dog an approaching person brings good things.
- Separation anxietySeparation anxiety is a fear response in which a dog panics when left alone or apart from the person it is attached to. Signs include howling, destruction near doors, toileting indoors, drooling and escape attempts, usually worst in the first 30 minutes. It is treated with gradual, reward-based training, sometimes alongside medicine from a vet, never with punishment.
- Urine markingUrine marking is using small amounts of urine as a scent message rather than to empty the bladder. Cats usually spray backwards onto upright surfaces with the tail raised and quivering; dogs lift a leg against furniture or doorways. It is commoner in unneutered animals and stressed or crowded homes. Rule out illness first, then reduce the stress behind it.
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Sources
Each source was opened and read on the date shown. How Petym checks its sources
- International Cat Care: Soiling indoors (updated 26 September 2025) (opens in a new tab)
- International Cat Care: Feline lower urinary tract disease (updated 28 November 2025) (opens in a new tab)
- International Cat Care: Urine spraying in cats (updated 26 September 2025) (opens in a new tab)
- AAFP and ISFM (Journal of Feline Medicine and Surgery, 2013): Feline environmental needs guidelines (opens in a new tab)