When a cat pees outside the litter box

A cat that suddenly pees outside the litter box is telling you something is wrong, and the first cause to rule out is medical. Book a vet visit. If your vet finds no illness, look at the box, the litter, the location and the stress in the home. Clean accidents with the right cleaner, fix the setup and never punish the cat.

Peeing outside the box is one of the commonest reasons people give up a cat, and it is also one of the most fixable. The cat is not being spiteful. It has a reason, even when you cannot see it yet.

Is it an emergency?

Go to a vet at once, today, if:

• A male cat strains to urinate, goes to the box again and again, cries or produces little or no urine. This can be a urinary blockage, which is life-threatening within a day or two.
• Any cat passes blood in the urine.
• The cat is vomiting, weak, hiding or refusing food as well.
• The cat has not passed urine in 24 hours.

Do not wait to see if it passes. Frequent small amounts of urine and licking at the genitals are warning signs, and they can resemble a behaviour problem.

Step 1: see your vet

Many cats that urinate outside the box have a medical problem. Common ones include:

• Bladder inflammation or other urinary tract disease. Veterinarians group these as FLUTD. One form is cystitis. Stress can trigger it.
• Crystals or stones in the urine.
• Infection.
• Kidney disease, diabetes and an overactive thyroid. These make cats drink and urinate more.
• Arthritis and joint pain. osteoarthritis makes it hard to climb into a box or squat, especially in older cats.
• Other pain or illness.

Your vet will ask about the pattern and examine the cat. Tests may include a urine sample (urinalysis) and blood tests. Bring notes on what, where and how often, and whether the cat strains, and take a photo of the box. Do not treat the cat yourself or use any human medicine.

Step 2: work out what kind of problem it is

Urinating (squatting). The cat squats and leaves a puddle on a flat surface such as a rug, bath mat or bed. This points toward a box problem or a medical cause.

spraying (marking). The cat stands, often with the tail up and quivering, and sprays a small amount of urine on a vertical surface such as a wall or a door. This is a communication problem. See our guide on why cats spray.

A cat can do both, so look for clues. Note where it happens, the time, and what changed.

Step 3: check the box

Cats have strong preferences. Check these:

• Size. The box should be big enough for the cat to turn around and dig. Many store-bought boxes are too small. Choose a large, open one.
• Number. Provide one more box than the number of cats, in different places. The litter boxes and new-cat checklist tool helps you plan this for a multi-cat household.
• Location. Choose quiet, easy-to-reach places. Avoid noisy machines, cold basements and spots where another cat or a dog can ambush the cat.
• Entry. Older or sore cats need a low entry. A very high side can put them off.
• Cleanliness. Scoop at least once a day. Wash the box regularly with mild soap. Strong scented cleaners can deter a cat.
• Lids and liners. Some cats dislike covered boxes or liners. Try an open one.

Step 4: check the litter

A sudden change in litter can cause trouble. Cats often prefer a fine, soft, unscented litter. Keep the depth at a few centimetres. If you must change the type, mix the new litter in slowly or place a second box with the new type next to the old one so the cat can choose. Avoid litter additives and strong perfumes.

Step 5: look at stress and the household

Stress can cause a cat to leave the box. Common sources include:

• A new pet, baby or person.
• A move, new furniture or building work.
• Conflict with another cat, including a cat outside seen through the window.
• Changes in routine or the owner's time away.
• Fear of using the box because of an ambush or a bad experience such as pain while urinating. Cats can link the pain to the box, a condition called litter box aversion.

Give the cat secure hiding places, high perches, routine, play and separate food, water and boxes. Our guide to signs of stress in cats covers more.

Step 6: clean the spot properly

Cats return to places that smell of urine. Clean with a cleaner made for pet urine that breaks down the odour. Blot first, soak the area and let it dry. Avoid ammonia, which smells like urine to a cat. Test a small area first on fabrics. For a carpet or mattress, you may need to treat deeply or replace the item. A black light can help to find old stains.

Block the spot, cover it with foil or a plastic sheet, or put a box there for a while. Move food or toys to the area only if your vet or a behaviour specialist suggests it.

Common mistakes

• Assuming it is bad behaviour. Always rule out medical causes first.
• Punishing the cat. Shouting, rubbing the cat's nose or spraying water makes things worse and teaches the cat to hide when it goes.
• Changing many things at once. You will not know what helped.
• Using a strong cleaner.
• Too few boxes or boxes in one place.
• Leaving the box dirty.
• Waiting weeks. A habit gets harder to break the longer it continues.
• Confusing a blocked male cat with a naughty one.

When to call a vet

Call the same day for straining, blood in urine, crying in the box, vomiting or no urine. Book a prompt visit for any new or repeated urination outside the box. Ask for a referral to a qualified behaviour specialist if your vet finds no medical cause and the problem continues after you have fixed the box setup.

Summary

• Treat sudden peeing outside the box as a health question first.
• A straining male cat is an emergency.
• Provide enough large, clean, well-placed boxes and a litter the cat likes.
• Reduce stress and conflict in the home.
• Clean accidents with a pet urine cleaner.
• Never punish the cat.