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Home > Cats > Why Is My Cat Peeing in the Sink? 3 Possible Causes and Solutions!

Why Is My Cat Peeing in the Sink? 3 Possible Causes and Solutions!

orange cat in sink

Inappropriate urination is a big problem whether you’re talking about a cat or a person, but the horrible smell of cat pee definitely takes the cake when it comes to gross bodily fluids. Luckily, since most sinks aren’t made of porous materials (they wouldn’t be very good sinks if they weren’t), they won’t retain the smell of cat pee for very long. However, it’s still never fun to find your cat urinating in your lovely, clean sink.


Why Do Cats Urinate Inappropriately?

There are many reasons a cat may begin to urinate in inappropriate places. Most of them are medically benign, and you don’t necessarily have to worry about your cat dying from urinating in the sink.

Most commonly, cats urinating inappropriately do so because they’re displeased with some part of their environment. Pet parents may find that their cat stops urinating in places they should not when they correct the undesirable part of the cat’s environment.

An excellent way to think of it is that peeing and pooping inappropriately is a protest by the cat. The cat is telling you that something is wrong with their environment or body that needs to be redressed.

While not many medical issues cause inappropriate urination, it is still best to have your cat checked out by a veterinarian if you notice a persistent problem. A vet can best determine if the issue is medical.

Here are some reasons your cat may be urinating in your sink.

Reasons Your Cat May Be Urinating in Your Sink

1. Displeasure With Their Litter Box

maine coon on top entry litter box
Image By: Nils Jacobi, Shutterstock

The most likely reason your cat is urinating in the sink is that they hate their litter box. There are many reasons a cat might not like their litter box, and this “affliction” could strike at any time.

The solution to your cat’s litter box displeasure lies in the cause, and determining the cause starts with identifying if this is a new or persistent problem. If the problem is brand new, look for things that have changed about your cat’s litter box environment. Is it dirtier than usual? Have you changed the type of litter you’re using? Is the box different than usual?

Any change to the litter box environment could cause your cat to refuse to use it. They’re finicky little creatures who hate change. So, don’t be surprised if they hate the new decorations near their litter box.


Find out what’s wrong with your cat’s litter box and fix it. It may take some time before you’re able to identify what’s wrong with your cat’s litter box that they’re rebelling.

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2.  Displeasure With Other Changes to Their Environment

cat peeing on concrete ground
Image Credit: nanniezwawa, Shutterstock

Like we mentioned before, cats hate change. Any significant change to their environment, even if it has nothing to do with their litter box, could set off your cat and make them start acting out in anxiety or voice their displeasure with you.

If you’ve recently changed your work routine, bought a new sofa, or any other large-scale change to your environment, this could be making your cat uncomfortable and unhappy. Unfortunately, this isn’t so easily remedied as it’s not always feasible to change your work routine or chuck your brand-new sofa.


Pheromone diffusers can diffuse calming pheromones for your cat and help them feel more comfortable in their new environment. Putting these diffusers around your house can help your cat feel more secure knowing that this is their home!

3. Illness or Age

tired sick cat
Image Credit: natata, Shutterstock

Several illnesses may cause your cat to urinate inappropriately. If you think your cat is urinating inappropriately because of a medical issue, the best thing you can do is get them to a veterinarian who can oversee their recovery.

Feline Lower Urinary Tract Disease

FLUTD is a relatively common illness that afflicts cats. Cats with FLUTD may experience frequent or infrequent urination, discomfort when urinating, and may urinate inappropriately. Cats with FLUTD generally prefer to urinate on cool, smooth surfaces like tile floors, bathtubs, or sinks.

FLUTD is not usually a cause for great concern, and most cats experience a full recovery when placed under veterinary supervision.

Urinary Crystals

Cat urine contains crystallized minerals that are passed by the kidneys. When there is an overabundance of crystals in the urine, the cat may experience pain when urinating, and frequent urination as the body attempts to correct the mineral imbalance in the urine.

Because of the pain when urinating, cats with excess urinary crystals may urinate inappropriately or have accidents outside of the litter box.

Urinary Tract Infection

Urinary tract infections can happen amongst cats. Urine is generally sterile and cleans out the bladder and urethra, purging both areas of the body of bacteria as it passes. However, sometimes bacteria can get into the urethra or bladder and grow there, causing pain when urinating and frequent urination.

Cats with UTIs may experience sudden urinary urgency pain when urinating. They may have accidents or urinate inappropriately because they can’t hold their urine as they usually would be able to.


Aging is another reason your cat may begin to urinate in the sink. Like in people, cats can start to behave erratically as they age. The onset of mental aging like dementia may result in your cat forgetting about the litter box and using your sink instead.


The solution relies on what your cat’s medical issue is. Cats with FLUTD, a UTI, or urinary crystals should see improvement once a veterinarian intervenes and gets them back into shape.

However, an old cat may need environmental adjustments to access its litter box better and remember where it is. In some cases, you may have to put up with your cat doing undesirable things as they age, just as you would with a person.

Talk to your veterinarian to see what they think will work best for your cat and your situation. Together, you can formulate a plan to keep your cat comfortable and happy.


Final Thoughts

Inappropriate urination is a frustrating problem, but luckily, many solutions help quell the pain. As always, the first talk should be with your veterinarian. They have a more comprehensive overview of your cat’s behaviors and previous problems and can offer insight based on their personal experience with your cat.

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Featured Image Credit by: Okssi, Shutterstock

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