# Why Is My Cat Not Pooping in the Litter Box? Solutions If your cat is not pooping in the litter box, the cause is usually either a medical problem that makes pooping painful or a litter box setup that does not meet her needs. Cats rarely do this out of spite. The fix starts with a veterinary check, then a careful look at the box itself. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - Take your cat to a veterinarian first. Constipation, pain, and other medical issues can all cause litter box avoidance, and these need to be ruled out before you try behavior changes. - Most cats prefer a large, uncovered box with clumping clay litter, scooped daily [1][2]. - A general rule is one box per cat, plus one extra, placed in quiet spots your cat can reach easily. - Never punish your cat for going outside the box. Punishment increases stress and makes the problem worse. - Act fast. Once a cat starts preferring a surface like carpet or a rug, the habit can become long lasting [3]. ## Why Is My Cat Not Pooping in the Litter Box? Common Reasons ### Normal reasons first Sometimes the behavior is not really a problem. A kitten who is new to your home may not have learned where the box is yet. A cat in a new house may need a few days to settle in. A cat who just had a stressful event, like a move or a new pet, may avoid the box for a short time. Some cats also poop less often than you expect. Healthy cats do not poop on a strict schedule, and a cat who skips a day is not always sick. But if your cat goes several days without pooping, that is a medical concern, not a behavior quirk. ### The box itself may be the problem Cats are picky about where they eliminate. Research shows cats prefer litter boxes measuring at least 50 cm (about 20 inches) and clumping clay litter [1]. When cats got a box and litter that matched their preferences, their house-soiling improved, including pooping outside the box [1]. Other box factors matter too. A study of over 3,000 cats found that the number, type, and location of litter boxes, the type of litter, and how often the litter was scooped and fully replaced were all linked to house-soiling [2]. In other words, the box setup is often the whole story. ### Stress and conflict in the home Elimination problems can develop because of conflict between cats in a home [3]. If you have more than one cat, one may be guarding the box or blocking access. A cat who feels unsafe may hold her poop as long as she can, then go somewhere she feels secure. The number of dogs and other cats in the household was linked to house-soiling in one large study [2]. Changes like a new baby, a move, or a loud renovation can also trigger avoidance. ### Surface and location preference Once a cat avoids her box, she can develop a preference for a surface or a spot, like your living room rug or your favorite chair [3]. This is why timing matters. The longer she practices pooping somewhere else, the harder it is to change. If your cat is pooping outside the box but still urinating inside it, that pattern points strongly toward a medical or box-related cause. You can read more about that pattern in [Why Is My Cat Pooping Outside the Litter Box? Causes and Solutions](/knowledge/veterinary-medicine/anxiety-and-behavior-support/cat-pooping-outside-litter-box). ## Medical Causes to Rule Out ### Constipation and pain Constipation is one of the most common reasons a cat stops pooping in the box. When pooping hurts, a cat learns to link the box with pain and avoids it. She may associate the box itself with the discomfort, even after the constipation is treated. ### Chronic kidney disease Cats with chronic kidney disease (CKD) are at higher risk for constipation [4]. A study that tracked defecation with a smart litter box monitor found that cats with CKD had significantly more days without defecation than healthy cats over 14, 21, and 30 days [4]. Cats with CKD also showed more urination, longer elimination times, and less covering after elimination [5]. This matters for you because kidney disease is common in older cats and often hard to spot early [5]. If your cat is middle aged or older and her litter box habits changed, ask your veterinarian about bloodwork and a urinalysis. ### Other medical triggers Many conditions can change elimination behavior. These include arthritis, which makes it hard to squat in a box with high sides. Anal gland problems, intestinal parasites, inflammatory bowel disease, and neurologic issues can all play a role. A foreign object or a mass in the colon is less common but serious. If your cat is straining, crying, or producing small amounts of poop, that is a medical visit, not a training problem. ### Why kittens are different A kitten not pooping in the litter box often has a simpler explanation. Young kittens may not recognize the box yet, may be startled by it, or may have been separated from their mother before they learned. A kitten who is not pooping at all, or who seems uncomfortable, needs a veterinarian right away. Young kittens can dehydrate and decline quickly. If your kitten is also not peeing, that is more urgent. A kitten who cannot urinate can become dangerously ill within a day. Learn more in [Cat Not Using Litter Box](/knowledge/veterinary-medicine/clinical-methods/cat-not-using-litter-box). ## When Does Pooping Outside the Box Become a Problem? It becomes a problem the moment it starts, because avoidance can become chronic [3]. At least 10% of all cats develop elimination problems, and some stop using the box altogether [3]. House-soiling is the most common problem cat owners face, and it is the main reason owners surrender cats to shelters [1]. That is not meant to scare you. It is meant to show you that early action works. The pattern matters. A cat who poops outside the box once after a stressful day is different from a cat who has done it daily for two weeks. A cat who poops in the same corner every time has already formed a location preference. A cat who poops in different spots may be reacting to pain or stress. Track it. Write down when your cat poops, where, and what it looks like. Note whether she strains, whether the poop is hard or small, and whether she is eating and drinking normally. This record helps your veterinarian a lot. ## What to Do Step by Step ### Step 1: See your veterinarian Book a visit before you change anything else. Your veterinarian will examine your cat, ask about her diet and habits, and decide whether testing is needed. If constipation or another condition is found, treatment comes first. Behavior plans rarely work while a cat is in pain. Do not give your cat any medication, laxative, or supplement on your own. Your veterinarian calculates the dose from your pet's weight and health. ### Step 2: Fix the box setup Start with size. Choose a box at least 50 cm (about 20 inches) long, since cats prefer boxes this size [1]. Many commercial boxes are too small. Use clumping clay litter, which cats preferred in the same study [1]. Keep the litter depth to about two to three inches. Most cats do better with an uncovered box, because covers trap odor and make some cats feel trapped. Scoop at least once a day and fully replace the litter regularly. Litter hygiene was linked to house-soiling in a large study of cats [2]. A dirty box is one of the easiest problems to fix. ### Step 3: Add boxes and place them well Provide one box per cat, plus one extra. If you have two cats, that means three boxes. Place them in quiet, low-traffic areas with more than one exit route. Do not line them all up in the same room, because a cat who is bullied at one box needs another option. If your cat has trouble squatting, try a box with low sides. Senior cats and cats with arthritis often do better with easy entry. ### Step 4: Reduce stress Think about what changed. A new pet, a move, a new baby, or a change in schedule can all trigger avoidance. Give your cat a quiet room with her own food, water, and box during transitions. If you have multiple cats, add resources. Separate feeding stations, water bowls, and resting spots reduce competition. A cat who feels crowded may avoid the box even when it is clean. ### Step 5: Make the wrong spot less appealing If your cat has picked a spot, make it less attractive. Place a box right on or next to that spot for a while. Once she uses the box reliably, move it a few inches a day toward where you want it. Clean soiled areas with an enzymatic cleaner made for pet waste. Regular cleaners may leave a scent that invites your cat back. Block access to the spot when you can, but always give her a better option nearby. ### Step 6: Reward success When your cat poops in the box, stay calm and quiet. Do not chase her or praise loudly, which can startle her. A calm, predictable routine is the reward. Cats respond to consistency more than to treats for this behavior. For a kitten who will not poop in the litter box, keep her in a small, safe room with the box close by at first. This makes the box the easiest choice. Expand her space as she gets reliable. If the problem continues, a certified behavior professional can help. Your veterinarian can refer you. You can also review [Cat Litter Box Problems](/knowledge/veterinary-medicine/clinical-methods/cat-litter-box-problems) for more detail on box management. ## What Not to Do ### Do not punish your cat Never rub your cat's nose in the mess, yell, or use a spray bottle. Punishment does not teach a cat where to go. It teaches her that you are scary, and it can make her hide her elimination even more. Stress makes litter box problems worse. ### Do not lock her out of the room Blocking a room does not solve the problem. Your cat will simply choose another spot. The goal is to make the box the best option, not to remove every option. ### Do not assume it is behavioral This is the most common mistake. If you skip the veterinary visit, you may miss constipation, kidney disease, or pain. Treat the body first, then the behavior. ### Do not switch everything at once If you change the box, the litter, the location, and the food all in one week, you will not know what helped. Change one thing at a time and give it a week or two. ### Do not wait too long Avoidance can become a chronic problem once a surface or location preference forms [3]. Quick action is one of the best things you can do. ## Limitations and When to Contact a Veterinarian This article covers common patterns, but every cat is different. Individual cases need a veterinarian who can examine your cat and run tests. Contact your veterinarian the same day if your cat is straining to poop, crying while trying, passing small amounts of poop, vomiting, or has not pooped in more than 48 hours. Also call if she is eating less, hiding, or seems painful when you touch her belly. Go to an emergency clinic now if your cat is open-mouth breathing, collapsed, repeatedly vomiting, or has a hard, painful belly. These can be signs of a blockage or another emergency. Schedule a routine visit if the behavior changed gradually, if your cat is older, or if she has a known condition like kidney disease. Cats with CKD defecate less often than healthy cats, so changes in her habits deserve attention [4]. If your cat is hiding along with the litter box changes, that combination is worth a prompt call. See [Why Is My Cat Suddenly Hiding and Not Using the Litter Box?](/knowledge/veterinary-medicine/anxiety-and-behavior-support/cat-suddenly-hiding-not-using-litter-box). ## Frequently Asked Questions ### Why is my kitten not pooping in the litter box? Kittens often have not learned the box yet, or the box may be too big, too high, or in a scary spot. Keep your kitten in a small, quiet space with a low-sided box nearby, and see a veterinarian if she is not pooping at all or seems uncomfortable. A kitten who is also not peeing needs urgent care. ### Why is my kitten not peeing in the litter box? A kitten who is not peeing may have a urinary blockage, which is an emergency, especially in males. Call your veterinarian or an emergency clinic right away if your kitten is straining, crying, or producing no urine. Do not wait to see if it improves on its own. ### My kitten won't poop in the litter box but pees there fine. What does that mean? This pattern often points to pain or constipation, because pooping hurts while peeing does not. It can also mean the box is fine for urine but not comfortable for squatting and pushing. Have your veterinarian check her before you focus on training. ### Can stress really stop my cat from pooping in the box? Yes. Conflict between cats, new pets, moves, and other changes can all trigger elimination problems [3]. The number of other cats and dogs in the home was linked to house-soiling in a large study [2]. Reducing competition and giving your cat quiet, separate resources often helps. ### How long should I wait before calling the vet? Call the same day if your cat has not pooped in more than 48 hours, is straining, or seems painful. If the change is mild and your cat is otherwise normal, a routine visit within a few days is reasonable. Do not wait weeks, because avoidance can become a lasting habit [3]. ## Related Articles - [Why Is My Cat Pooping Outside the Litter Box? Causes and Solutions](/knowledge/veterinary-medicine/anxiety-and-behavior-support/cat-pooping-outside-litter-box) - [Cat Litter Box Problems](/knowledge/veterinary-medicine/clinical-methods/cat-litter-box-problems) - [Cat Not Using Litter Box](/knowledge/veterinary-medicine/clinical-methods/cat-not-using-litter-box) - [Cat Not Pooping but Eating Normally: Causes and When to Help](/knowledge/veterinary-medicine/digestive-and-urinary-care/cat-not-pooping-eating-normally) - [Why Is My Cat Suddenly Hiding and Not Using the Litter Box?](/knowledge/veterinary-medicine/anxiety-and-behavior-support/cat-suddenly-hiding-not-using-litter-box) - [Why Is My Cat Peeing Outside the Litter Box?](/knowledge/veterinary-medicine/symptom-guides/cat-peeing-outside-litter-box) - [How to Stop Your Cat Pooping Outside the Litter Box](/knowledge/veterinary-medicine/digestive-and-urinary-care/stop-cat-pooping-outside-litter-box) - [Why Your Cat Keeps Pooping on the Floor (Not Peeing)](/knowledge/veterinary-medicine/digestive-and-urinary-care/cat-pooping-on-floor-causes) - [Why Is My Cat Pooping in the Sink? Causes and Solutions](/knowledge/veterinary-medicine/digestive-and-urinary-care/why-is-my-cat-pooping-in-the-sink) ## References 1. [Litter box size and litter type preference and their associated behavioral changes in cats](https://pubmed.ncbi.nlm.nih.gov/40204471/). The Journal of veterinary medical science, 2025. 2. [Factors associated with house-soiling in Italian cats](https://pubmed.ncbi.nlm.nih.gov/37975187/). Journal of feline medicine and surgery, 2023. 3. [Litter Box Problems](https://www.aspca.org/pet-care/cat-care/common-cat-behavior-issues/litter-box-problems). ASPCA Animal Poison Control Center. 4. [Quantification of defecation frequency in cats with and without chronic kidney disease](https://pubmed.ncbi.nlm.nih.gov/40678920/). Journal of feline medicine and surgery, 2025. 5. [Enhancing Detection of Feline Chronic Kidney Disease Through Smart Litter Box Monitoring](https://pubmed.ncbi.nlm.nih.gov/42121739/). Animals : an open access journal from MDPI, 2026. ## Further Reading - [Merck Veterinary Manual: Cat Owners](https://www.merckvetmanual.com/cat-owners) - [Cornell Feline Health Center: Health Information](https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information) - [American Veterinary Medical Association: Pet Care](https://www.avma.org/resources-tools/pet-owners/petcare)