Why Is My Cat Pooping Outside the Litter Box? What to Do

Why is my cat pooping outside the litter box? It’s one of the most common and frustrating cat problems, and it almost always has a fixable cause. Vets split the causes into three groups: health problems, litter box problems and stress. This guide explains what to check first and how to get your cat back in the box.

Rule Out Medical Causes First

Vets are clear on the order. The ASPCA says the first step is to rule out medical problems and urine marking. Many cats that go outside the box are uncomfortable or in pain, and no change to the box will fix that.

Here are the medical causes named by veterinary sources:

Pain can make the box itself feel like the problem. A cat with a sore back may struggle to climb over a high edge or squat comfortably. A constipated cat may strain, give up and finish elsewhere.

Call your vet right away if your cat strains in the box with little or nothing coming out, cries while going, or seems unwell. Urinary blockages, which the ASPCA lists among the causes, need urgent care.

Pooping vs Peeing Outside the Box

Where and how your cat goes gives useful clues. Pooping and peeing outside the box often point in different directions:

VCA’s veterinary behaviorists explain that marking usually means spraying urine on vertical surfaces, often with a quivering tail. The ASPCA adds that a marking cat usually keeps using its box normally, while also leaving urine elsewhere. House-soiling, by contrast, means going on flat surfaces instead of the box.

Litter Box Problems That Push Cats Out

Once your vet has ruled out illness, the box is the next suspect. The ASPCA lists a box that’s too small, a hood or liner, a change in litter and an unwelcome location among the main causes. The fixes are usually simple:

• Dirty box: scoop at least once a day, as the ASPCA and VCA both advise.
• Too few boxes: keep one per cat plus one extra, in separate places.
• Box too small: aim for about one and a half times your cat’s length.
• Covered box: most cats prefer an open box, per Cornell.
• Liner: the AAFP and ISFM advise against liners.
• New litter: switch gradually, mixing new into old, as Cornell advises.

Scented litter deserves a special mention. In a 1997 study by Horwitz, scented litter was significantly more common among cats referred for house-soiling than among cats without problems. The Oregon VMA notes that most cats prefer clay clumping litter in a large, open box. My guides on unscented cat litter and how many litter boxes per cat cover both points.

Where the Box Is Placed

Location matters more than many owners expect. The ASPCA notes that cats develop preferences for where they go and may avoid spots they dislike. The Oregon VMA recommends quiet areas away from high traffic, and the AAFP and ISFM advise keeping boxes away from food and water.

A box beside a noisy appliance, in a busy hallway, or where another cat can corner your cat is worth moving. Try a calmer spot and see whether the accidents stop.

Stress and Changes at Home

Cats are sensitive to change. The ASPCA points out that moving, a new pet or family member, or even a change in your daily routine can make a cat anxious enough to avoid the box. Tension between cats in the same home can be a trigger too, especially if one cat blocks another’s way to the box.

VCA’s behaviorists note that when stress, anxiety or marking is behind the problem, a vet may recommend behavior modification and sometimes medication. If the accidents started after a change at home, mention it to your vet.

Senior and Arthritic Cats

Older cats often start having accidents because getting into the box has become hard. VCA recommends moving the box somewhere easier to reach, improving the lighting, and offering a larger box with lower sides. The Oregon VMA also suggests low-sided boxes for cats with joint or arthritis issues.

Look for a box with a low entry and plenty of floor space. My large cat litter box guide includes a 3-inch low-entry option suited to seniors.

A Step-by-Step Plan to Stop It

Work through these steps in order. Each one builds on the vet guidance above:

1. Book a vet visit to rule out pain and illness.
2. Clean every accident with an enzymatic cleaner.
3. Scoop daily and wash the box regularly.
4. Add boxes until you have one per cat plus one.
5. Switch to a large, open box with unscented clumping litter.
6. Move boxes to quiet spots away from food and traffic.
7. Put a box right where the accidents keep happening.
8. Reduce stress and give each cat its own space.

The Oregon VMA suggests placing a litter box over the spot where your cat keeps going, which can steer it back to using a box. Once the habit is back, move that box gradually to where you’d like it.

What Not to Do

It’s natural to feel frustrated, but punishment makes things worse. The ASPCA warns never to rub your cat’s nose in urine or feces, scold it, or carry or drag it to the litter box. These reactions add stress and can teach your cat to hide when it goes.

Harsh cleaners are also a mistake. The AAFP and ISFM advise against strong chemicals and ammonia-based products, and the ASPCA recommends an enzymatic cleaner designed to neutralize pet odors instead.

How to Clean Up Accidents Properly

Leftover odor can draw a cat back to the same spot. The ASPCA recommends cleaning accidents thoroughly with an enzymatic cleanser designed to neutralize pet odors. Soak the area, let the cleaner work, and keep your cat away until it’s dry.

For the box itself, VCA suggests scooping daily and emptying and washing the box about once a week. My guide on how to get rid of litter box smell covers cleaning in more detail.

The Bottom Line on Litter Box Accidents

Frequently Asked Questions

Why is my cat suddenly pooping outside the box?

A sudden change often has a medical cause, such as constipation, colitis, anal sac disease or joint pain, so see your vet first. If your cat is healthy, look for recent changes: a new litter, a moved or dirty box, a new pet or a shift in routine. The ASPCA notes that even small changes can stress cats.

Why does my cat poop next to the box?

It often means the box itself is the problem. The box may be too small, too hard to climb into, dirty, or covered. Pain can also play a part: a cat with arthritis or constipation may struggle to squat in the box. See your vet, then try a larger, low-sided, open box.

Can stress cause litter box accidents?

Yes. The ASPCA lists moving, new pets or family members, and changes to your routine as common triggers. Tension between cats can also keep one cat away from the box. Reduce stress, add boxes in separate locations, and talk to your vet if it continues.

How do I stop my cat peeing outside it?

Start with a vet check to rule out urinary problems, which are common and can be urgent. Then clean accidents with an enzymatic cleaner, scoop daily, keep one more box than you have cats, and use unscented clumping litter in a large, open box in a quiet spot.

Should I punish my cat for accidents?

No. The ASPCA warns against rubbing your cat’s nose in accidents, scolding, or dragging it to the box. Punishment adds stress and can make your cat hide when it goes. Focus on finding the cause and making the box more appealing instead.