Why is my cat pooping outside the litter box? A vet's guide

cat outside litter box
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No one wants to come home to find poop on the floor, but unfortunately, for some cat owners this can become a regular occurrence. A cat can start pooping outside the litter box for many reasons, some behavioral and others due to underlying medical issues.  

If you’re dealing with a cat pooping outside the litter box, there are some steps you can take to get your cat back to the box. First, you’ll need to troubleshoot your litter box management and see what may be causing your cat’s sudden litter box aversion. You’ll also need to consider whether your cat’s inappropriate elimination could be due to a medical problem, and consult your veterinarian for further advice.  

Why do cats poop outside the litter box? 

There are many reasons why a cat may start pooping outside the litter box, and it can be difficult to ascertain why your cat has started this new behavior. Some of the common reasons for pooping outside the litter box include: 

  • Dirty litter box 
  • Aversion to litter or the litter box 
  • Pain 
  • Parasites 
  • Constipation 
  • Diarrhea 
  • Arthritis 
  • Inter-cat aggression 
  • Incontinence 
  • Territorial marking 
  • Gastrointestinal problems 

how to get a cat to use a litter box

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How to stop a cat from pooping outside the litter box 

If your cat is frequently pooping outside their litter box, the good news is there a few things you can try to resolve the behavior. A visit to your veterinarian will rule out any medical issues but good litter box management is also essential. 

1. Consult your vet

To get to the bottom of what’s making your cat poop outside the litter box, the first step is a visit to your veterinarian. Your veterinarian will perform a full head to tail physical examination, and may recommend some additional diagnostic testing such as radiographs (x-rays) or evaluation of a fecal sample. 

These tests will help your veterinarian rule out common causes for pooping outside the litter box and, hopefully, achieve a diagnosis for your cat. 

2. Keep their routine consistent

One of the most common reasons cats poop outside the litter box is an aversion to the litter box itself. Cats can be extremely picky about their litter boxes and even minor changes can cause them to stop using the box.  

If your cat is pooping outside the litter box and you have recently made some changes – such as buying a new type of litter or changing the location of the box – try reversing those changes first to see if this will encourage your cat to use the box again. 

3. Litter box management

When dealing with inappropriate elimination, good litter box management is essential. First, make sure you have enough litter boxes – at least one box per cat in the household, plus one extra.  This ensures there is always a box available when your cat needs one. The litter boxes must be cleaned at least once a day.  Some cats who are extra fastidious may not use a dirty litter box at all, so you may need to clean the box even more frequently in these cases.  

Be sure to offer different sizes and types of litter boxes, so your cat can choose what he likes best. Use a clumping, unscented clay litter, because this is what most cats prefer. 

 The litter boxes should be located in different spots throughout the house so there is always one easily accessible.  If your cat is pooping outside the litter box, putting a box where he most commonly poops may encourage him to use the box again. 

is your cat allergic to litter?

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4. Consider the location of litter box

Finally, take some time to consider the route your cat takes to reach the litter box.  What obstacles does your cat encounter along the way?  Does he have to cross the path of a scary dog, or does a bully cat stand in his way?  Will he have to go up and down stairs, or jump over obstacles to reach his box?  Is the litter box next to a noisy appliance or in a musty-smelling corner of the basement?  

All of these factors can make your cat less inclined to make the journey to the litter box.  Consider adding new boxes in more easily accessible areas of the house and this may resolve your cat’s inappropriate elimination issue.

How to discipline a cat for pooping outside the litter box

While inappropriate elimination may cause not only worry in cat owners, but frustration, it's important to understand that the resolution does not involve disciplining your cat.

Your cat isn’t pooping outside the litter box out of spite, and they aren’t being naughty. There is an problem that needs to be addressed. If the underlying issue is not treated, then inappropriate elimination will continue or worsen. 

Cat coming out of litter tray

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Why is my cat pooping on the floor with a clean litter box? 

If your litter boxes are well-managed and your cat continues to poop outside the litter box, it is definitely time to see your veterinarian to get to the bottom of the issue. Your veterinarian can help you further troubleshoot your litter box management, and can also assess your cat for medical problems such as pain and arthritis, which can commonly cause inappropriate elimination.  

If your cat is painful it can be very difficult to get into and out of the litter box, especially if there are obstacles along the way such as stairs, which can be quite painful for an arthritic cat to navigate. 

In many cases, treating the pain and providing a more easily accessible litter box can resolve the problem.  Other causes of inappropriate defecation, such as parasites or constipation, can also be resolved with appropriate treatment.

When to be concerned when a cat poops outside their litter box 

If your cat has pooped outside the litter box once or twice and then returned to using the litter box normally, this is likely not cause for concern.  Your cat may have been blocked from reaching the litter box or may not have been able to get to the litter box quickly enough. 

It’s always a good idea to periodically review your litter box management, so this is a great time to double check that you are following all of the recommendations above to give your cat a clean and welcoming litter box.  If your cat does not poop outside the litter box again, then there’s likely no cause for concern.

If your cat continues to poop outside the litter box, then it’s best to see your veterinarian for an examination and diagnostic testing.  Your cat may have an underlying medical issue contributing to the inappropriate defecation.  Once an underlying cause for the inappropriate defecation is diagnosed, your veterinarian can prescribe appropriate treatment to help get your cat back on track.

How to train an outdoor cat to use a litter box

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Inappropriate defecation can be a messy problem, but there is hope!  In some cases, good litter box management may be all that is needed to get your cat back into the box.  In more severe cases, working with your veterinarian to identify both the medical and behavior aspects of this problem will help you get your cat back to using the litter box appropriately.   

Elizabeth Racine, DVM

Dr. Elizabeth Racine is a small animal general practice vet covering all things pet health and wellness.  Her special interests include veterinary behavior, nutrition, and internal medicine.  As a freelance writer, Dr. Racine has written content for major companies in the industry such as the American Kennel Club, Merck Animal Health, Bayer PetBasics, Elanco, and CareCredit.  In her free time, Dr. Racine enjoys playing trampoline dodgeball, hiking with her beagle Dasher, and spending time with her three mischievous cats.