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Cat sitting on s toilet seat
Image by Alexas_Fotos from Pixabay 

Cats are naturally clean and appealing creatures that do not smell even after going days without a bath. 

That’s probably one of the reasons why you choose them in the first place.

But the reality is that most of the things associated with cats stink. Their urine somehow gets everywhere and it stinks, their food smells horrible, and their litter box? Don’t even go there. The stench from their litter box smells like ammonia and is strong enough to take up the whole house.

Doesn’t have to be that way. In today’s article, I’m going to show you how to get rid of the stench given off by the cat litter box so your house can smell fresh and light again.

Let’s begin by finding out why a cat litter box smells so bad?

Why do cat litter boxes smell so horrible?

First off, let’s be realistic. It doesn’t matter how much attention it gets; a cat’s litter box is never going to smell like roses. And that’s primarily due to the odorant release into the air during the decomposition of urine. The two main causes are: 

Ammonia, the stench-lord. 

Ammonia is a highly volatile compound that is only detectable by humans at small concentrations. This is the primary cause of bad odor that emanates from the cat litter box. And it has a characteristic fishy odor that easily accumulates and smells up the whole house.  

Ammonia is a by-product of the bacterial decomposition of urea, which is the primary content of urine.

Illustration of how ammonia is formed from urine
The process of ammonia formation.

How do the bacteria come about?

Well, they are everywhere! Some are floating in the air, some on your skin, tabletops, and other surfaces. And cats often carry bacteria picked up from the environment.

The cat litter box provides these bacteria a warm and safe accommodation, and a dependable energy source to feed on.

Some of the bacteria present in a cat’s litter box are specialists at converting urea to ammonia. Those that do, produce an enzyme known as urease which quickly breaks urea into carbonic acid and ammonia.

But that’s not enough to explain the strong smell, is it?

The other reason cat litter boxes smell so horrible is because cat urine has a higher urea content than humans and dogs. 

Felinine decay.

Felinine is a cat pheromone that’s present in the urine of some members of the Felidae family. When this compound (felinine) degrades, the by-product is a sulfuric compound known as thiol. Thiol is responsible for the recognizable ‘catty’ odor, and it also contributes to the offensive litter box smell.

Cats start secreting felinine from the age of 3 months. However, the concentration is higher in intact males than it is in castrated males and adult females. The degradation of felinine also generates a sour-smell compound known as pyruvic acid. 

These all combine to the overall horrible smell cat litter boxes give off.

So you see, you can’t entirely get rid of this odor. However, most cat owners take this too casually. They learn to live with the odor, which is just horrible. 

First off, it’s embarrassing, the smell stresses the brain, and it finds a way onto your clothing. Secondly, a cat has a sense of smell that’s 20 times better than that of a human. So, if the smell of the litter box is disturbing to you, then imagine what your cat goes through. Heck, if your cat cannot withstand the smell of the litter box anymore, she’ll stop using it.

That being said, here’s how to control litter box odor and keep litter box from smelling up the house. The buck starts with your litter manufacturer.

4 Ways Cat Litter Tries To Control Horrible Odor.

Cat litter manufacturers apply one of two main approaches to reduce the stench oozing from the litter box. They can either inhibit unpleasant odor from forming or come up with solutions to manage the smelly compounds once they’re formed. 

1. Prevent the formation of odor.

This is, without a doubt, the best approach to manage bad odor from a litter box. The way it works is quite impressive, and is very useful, especially against unpleasant odor that build up over time. Some common approaches that limit the degradation of urea and ammonia formation are:


Since bacteria is responsible for the breakdown of urea to ammonia, it is only natural that managing bacteria in the litter slows or stops the formation of ammonia. When the bacteria die, the urease contained in their cells are still released into the urine, so the process doesn’t end abruptly. However, it stops the bacteria from multiplying like they normally would.  

Since antibacterial litter doesn’t exactly prevent the formation of ammonia, it should be used alongside an anti-odor solution. 

Urease inhibitors.

Here, manufacturers use some sort of blocker that restricts the activity of urease once they are formed. This prevents the formation of ammonia. 

2. Odor canceling. 

Acting directly on the smell compounds is another effective way to fight hideous smells in the litter box. Litter manufacturers achieve this by adding special compounds in the liter. These compounds react with the smelly compounds and they cancel each other, thereby preventing smells in the house. However, these anti-smell compounds deplete fast – depending on how often your cat uses the litter – since they’re always active. 

3. Masking odor.

Some manufacturers add fragrances to their litter, not to fight smell, but to cover up any odor coming out. What this does is make the odor oozing from the litter box less offensive to the olfactory system. 

The problem, however, is choosing a fragrance that’s pleasant to the owner as well as the cat. Many cats might get irritated and stop using the litter box if the fragrance in the litter is too strong. 

4. Suppression of olfactory receptors.

The last trick up their sleeves is to add compounds in the litter that blocks or reduces olfactory reception. This effectively reduces the perception of bad odor from the litter box. The downside is that it might affect other smells as well. 

Aside from dealing with unprovoked aggression in cats, litter box odor is another nuisance of cat ownership.

While it’s a good thing that litter manufacturers apply several solutions to help fight bad odor, there are a couple of things that you can do to keep litter boxes from smelling up the house.

What Can You Do To Control Litter Box Odor?

Now that you know why cat litter boxes often have strong pungent smell, how can you manage and possible eliminate the horrible odor from your home?

1. Choose the right brand of litter. 

There are many varieties and brands of cat litter. Some of the best cat litter for odor control are:

  • Clumping clay litter: this is the most common type of litter in the market. They solidify any liquid into clay-like chunks that can easily be scooped out. However, it can cause intestinal blockage when ingested (cats love to groom) and even death, especially in kitties. 
  • Natural clumping Litter: to counter the problem of intestinal blockage when clumping clay litter is ingested, many natural alternatives made of pine, wheat, and corn are available. These will digest or breakdown when ingested. However, they don’t do much to keep the litter from smelling up the house, others clump poorly, and some track far too much.
  • Crystal litter: this is made of silica gel, the stuff inside those “do not eat” bags. It is very effective at absorbing urine and odor, plus it can last for several days without needing complete replacement.  

With this many options to choose from, it is often a challenge figuring out which cat litter is right for your cat and for eliminating odor.

You’ll have to perform a simple test to find the best litter box for odor control. What you’ll have to do is purchase the minimum size of several litter brands. Using a cup, measure each of them into different containers, and add a quarter cup of ammonia to each container. Let it sit undisturbed for a couple of hours then sniff the containers to perceive which one controlled the odor most.  

Most cats dislike the artificial smell in scented options, so try to avoid those with a very strong scent. If you’re switching litter, try to do so gradually. Cats hate sudden changes and might lose appetite in food. Trust me, it’s no fun running around trying to figure out how to stimulate appetite in a cat that won’t eat.  

2. Choose the right type of litter box!

You can convert almost any plastic container to a litter box, provided it can easily be cleaned. However, litter boxes like the Non-stick BetterBox from PetFusion have a gloss finish on the inside that prevents the plastic material from absorbing bad odor.

When getting a litter box, bigger is better. Pick one whose length is twice the adult-size of your cat from chin to tail and the width is as wide as your cat’s length. That’s because cats are particularly concerned with cleanliness and hate to step in already soiled areas. 

If the litter box is too small, your cat is more likely to mess up the sides of the box. Plus, it’ll have less space to move around which means a harder time burying waste. 

Ensure the litter box has at least one side that’s low enough for kitty to step in and out easily. If climbing in is a hassle for your cat, it’ll likely take its business somewhere else – the floor seems fitting. 

I recommend you go for open boxes. Enclosed boxes trap the odor inside the hood and lots of cats do not like entering them. Could be claustrophobia or the strong smell. However, if you can find one that works for you, then go for it!

Another option worth considering is the self-cleaning litter boxes. They’re perfect for owners that are gone for extended periods and those that feel lazy scooping out litter waste. Be sure the boss likes it though. 

3. Look into your cat’s diet.

Cat food brands
Your cat’s diet contributes to the smell of the litter box.

Many times, the litter and litter box are working very hard to prevent horrible odor from smelling up the house but your cat’s droppings are particularly foul-smelling.

If your cat’s dropping smell so unpleasant, ask your vet to recommend a safe and healthy diet. More often than not, this will be more expensive than cheaper brands. You need to understand that some cheap food brands simply fill up a cat’s belly but have difficulty digesting. The result is a strong stench each time kitty uses the litter box.

While at it, get your cat to drink more with a cat water fountain. When a cat drinks enough water to support the digestion of food, her waste products are less likely to smell pungent.

4. Keep things clean.

The steps before this will take you far, but not all the way. If you want to keep a litter box from smelling up the house, you have to clean it constantly. This means scooping out the smelling stuff at least once a day – preferably twice – with a large non-stick stainless steel spoon. Add litter as needed to replace what is removed.

Do that every day and your nose will thank you as well as your cats. Cats are likely to poop and pee on the floor if there’s too much waste to navigate.

One more thing, you have to wash the box frequently using a mild, unscented soap or mild bleach spray solution (one part bleach diluted in 20 parts water). Make sure to rinse off the container thoroughly and let it dry before adding 3-4 inches of litter. 

You can take things to another level when cleaning the litter box by wiping it with vinegar. Vinegar does an amazing job controlling odor and disinfecting surfaces. Wanna know what the best part is? Vinegar doesn’t smell bad when it dries.  

“Mehhh, that’s too much of a hassle. I’ll just get an automatic scooping box!”

My advice? 

Do not dispose of the old litter box when you get the automatic scooping box. Make sure you thoroughly test the new litter box and that your cat likes using it. The mechanical sound from some of these self-cleaning litter boxes can startle cats, causing them to do their business elsewhere. 

5. Improve ventilation.

Use fan for ventilation
Use fan for ventilation | Image by Bruno /Germany from Pixabay 

Tucking your cat’s litter box in a small, confined space seems like a good idea to control odor. However, to get rid of litter box stench forever, you need to improve ventilation where the litter box is. 

This will prevent odor oozing out of the litter box from smelling up the house. Trust me, without fresh air coming in to dilute and flush out the bad odor, even the best litter out there will struggle to control odor. 

Chances are, you will avoid this space or spend very little time in it. This means you’ll perform a lousy job when scooping out clumped waste – that’s so you can get out quickly. And your cat will likely do the same. 

The result? 

Your cat will avoid it too; after all, they have a stronger sense of smell. Would you rather clean up ‘accidents’ around the house?

So make sure there’s enough air circulation, but prevent drafts. If you have to, use a quiet, quick-mount fan and make it blow air outside. That way the fan pushes out the odor that was inside the house – don’t worry fresh, clean air will find a way in. 

6. Try not to mask the odor.

I don’t know which is more annoying, perceiving bad odor or your senses being bombarded with a confusing mixture of horrible and sweet smells.

For me, it’s the latter.

While most scented air fresheners work wonders on bad smells and are heavenly to humans, they’re gag-inducing to cats. Cats don’t perceive smell as a whole as we humans do. No, they perceive every single scent individually. 

That means when you use fragrance to cover up bad odor, they don’t perceive a combination of both. They perceive both bad odor and sweet fragrance. Imagine how confusing it can be for them, especially when you use more than one sweet-smelling product. 

7. Use charcoal filters for odor control.

Charcoal filters are an environment-friendly solution for controlling odor produced by hooded litter boxes. 

Though I’m not a fan of hooded litter boxes due to their tendency to trap odor. With the help of charcoal filters, bad smells can be absorbed instead of being trapped under the hood. When the current filter starts stinking, you just replace it with another while you sun-dry the used one. Repeat until all the filters are no longer as effective as before.  

8. Sprinkle baking soda on the litter.

Baking soda is a non-toxic, all-natural cat litter odor eliminator. All you have to do is sprinkle some in the bottom of the box before adding fresh litter each week. This will help absorb most of the smelly compounds and prevent them from building up in the house. Plus, it doesn’t irritate or upset your cat’s lungs or sensitive olfactory nerves.

You still have to scoop the litter, replenish or replace it, and thoroughly wash the box when necessary. I recommend choosing food-grade baking soda (i.e. one that’s meant for kitchen use) over scented options such as the Cat Litter Deodorizer. That’s because some cats might be repulsed by the strong smell of perfumed products. 

9. Replace the Boxes.

Plastic has one flaw; it absorbs the odor of its content over time. Some manufacturers have found a way around this. For instance, the  Non-stick BetterBox from PetFusion uses an FDA and EPA-approved non-stick coating that prevents the absorption of odor and is, well … non-sticky. 

However, over time, even the best plastic litter box will be defaced with scratches from the frequent clawing as cats bury their waste. These scratches are a good hiding place for ammonia-producing bacteria to hide in.

You should replace the litter box when it still gives off bad smells after thorough washing. Or get a quality stainless steel litter box that doesn’t absorb smells or get scratch marks. 

10. Accidents happen, clean them quickly and thoroughly.

When potty accidents occur, such as when your kitty soils the floor or misses the box. A good enzymatic cleaner and a few minutes of thorough cleaning will help control the odor and prevent bad smells from building up over time in the house.

Failure to neutralize the odor, and your cat will sniff out and soil the same spot again. 

11. How you manage cat waste matters.

Most cat owners scoop cat waste once or twice daily. However, unless you’re taking the waste outside, it is just sitting there smelling up the house. 

Cat waste cans do a pretty good job of controlling horrible odor. However, they’re mostly made of plastic and require filters, replacement parts, and all. 

I recommend using a diaper pail such as the Ubbi Diaper Pail or a bathroom step trash can. They are both made of stainless steel parts and are airtight solutions to the often fragile cat waste cans. 

Plus, you don’t need any proprietary bags to use these two. Any standard garbage bag will do. The only time you’ll perceive bad smells from these cans is when you open to deposit new waste. Soon as you close them and let the room air out, it’s all gone. 


Happy cat

Getting rid of cat litter box stench from the house takes work.

The procedure outlined in this article will push you several steps towards your dream of having a home that smell fresh and clean just as you envision it to be.

However, all these will be for naught except you dispose litter waste properly in an airtight litter waste disposal system. This, to me, is one of the most important step to eliminating litter waste odor from your home.

As a final note. You may be tempted to train your cat to use the toilet. But this is going against their natural behavior to something very new and, probably, uncomfortable. Likely, your cat won’t be able to keep up with the toilet training when age starts catching up with him or her.