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Help! My Cat Litter Box Smells Like Ammonia: 12 Ways to Fix It

by Ben Doyle | Reading Time: 6 minutes

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If your litter box smells like ammonia, it can cause problems. Not only will the smell drive you mad, but it can also be embarrassing if you have guests, or if people come to your home.

And in some cases, it can have a negative impact on the health of you and your cats.

In this article we’ll discuss:

  • Why cat pee smells so bad
  • Why the litter box can smell like ammonia
  • 12 ways to get rid of the ammonia smell in the litter box

Why Does Cat Pee Smell So Bad?

The reason why cat pee smells so bad is down to their evolution. 

Cats originated from the desert. As such, their bodies evolved to absorb lots of water from their urine to stay hydrated. 

This means they don’t need to drink as much water as other animals. It also means their urine is super concentrated and much darker. As a result, it stinks!

Male cats, especially intact males also have a pheromone in their urine called Felinine. On its own, it doesn’t smell much but as it breaks down, the smell gets stronger and stronger. Perfect for a wild cat, horrible for us domestic cat owners.

Why Cat Litter Box Smells Like Ammonia

Cat pee doesn’t just stink, it also contains a compound called Urea. As cat urine decomposes, bacteria break down the Urea and release ammonia.

In fact, this is the same reason many public toilets stink.

While in most cases it’s not harmful, if you or your cat have respiratory problems, this ammonia can cause;

  • Coughing
  • Wheezing, and
  • Short breath

Prolonged exposure can bring on Asthma attacks and even pneumonia.

How to Get Rid of the Ammonia Smell in the Litter Box

The good news is that there are plenty of things you to neutralize the smell of ammonia in cat litter.

Some are simple changes you can make to the way you manage the litter box. Others will cost a little money. How far you go will very much depend on how bad the problem is.

And you can use one or all of these suggestions. 

1. Teach Your Cat to Toilet Outside

If your cat is a house cat, then this probably won’t be an option.
But if your cat goes outside, try teaching them to go to the toilet outside. If they don’t do their business inside, you won’t have to smell it.

Even if they toilet outside half of the time, you’ll reduce the problem by 50% 

2. Scoop the Litter More Often

If you don’t scoop the litter box often enough, bacteria will start to break down urea and it will get smelly.

So, scoop the litter tray at least once a day. Twice a day is even better. If you can, do it as soon as your cat has been to the toilet.

The more cats you have, the more often you’ll need to scoop.

If you only scoop the litter box every other day, scooping more often could fix the problem.

3. Replace the Litter More Often

How often you replace the cat litter will depend on the type of litter you use.

If you use a clumping litter, scooping the clumps out will leave the litter box clean. Some cat owners who scoop very regularly never fully replace their litter. They can keep it so clean and odour-free that they don’t need to. That said, most of us should replace clumping litter every 2-4 weeks. 

If you use non-clumping litter, you’ll need to replace the litter at least once a week. It’s much harder to scoop wet litter if it doesn’t clump and if you miss bits, it will start to smell.

4. Clean the Litter Box More Often

No matter what type of cat litter you use, you should deep clean the litter box at least once a month. Even better, every time you replace the litter.

5. When You Clean the Litter Box, Use an Enzymatic Cleaner.

Make sure you use an enzymatic cleaner. These contain pro-bacteria and enzymes which break down and neutralise odours. They don’t mask it, they kill it.

Extreme Pet Stain and Odour Remover from Simple Solution is our favourite.

6. Consider Changing The Type of Cat Litter

Some types of cat litter are better at controlling odours than others.

For example, if you use wood pellet litter, you’ll know that it breaks down into dust when it gets wet. This makes it difficult to remove all the soiled litter when it’s wet. 

Chances are, every time you scoop, you leave at least some soiled litter behind which then starts to smell. If that happens every time you scoop and your cat pees on it again, you can see how the smell could become a problem.

Switching cat litter to a clumping version will help because you can scoop out all the mucky stuff.

7. Use More Litter Boxes

Using more litter boxes might sound counterintuitive. But if you have more than one cat and they all use the same litter tray, chances are, it’s going to smell. Especially if you don’t scoop or clean as often as you should.

By having the correct number of litter boxes, you won’t have so much cat pee concentrated into a single box.

8. Use Stainless Steel Litter Trays

Consider replacing your cats plastic litter box with a stainless steel one.

Stainless steel is much more hygienic than plastic. Plastic often scratches when your scrub it and those scratches can harbour bacteria.

Also, ammonia degrades plastic. This is why you often get those smelly white stains on the bottom of plastic litter trays. In fact, scrubbing them can make it worse. By scrubbing, you scratch the plastic even more, which perpetuates the problem.

You don’t have this problem with stainless steel litter boxes. They might be more expensive to buy but they won’t smell and last much longer.

stainless steel cat litter tray

Stainless Steel Litter Tray: Long Lasting & Hygienic

4.3 out of 5.0 stars (4.3)

Stainless steel is stronger than plastic and the ammonia in cat pee doesn’t degrade it, making it much more hygienic. Also our top choice for large cats.

9. If You Use Plastic Litter Trays, Replace Them Every Year

If you insist on using plastic litter boxes, make sure you replace them at least every year. You might find that even after a few deep cleans the bottom of the litter tray will start to scratch and turn white.

As soon as this happens, change it.

10. Try a Cat Litter Deodorizer

To prevent the build-up and smell of bacteria, try adding a cat litter deodorizer to the litter box.

It works by breaking down the bacteria which cause the smell.

All you need to do is give it a sprinkle on the top of the litter. If you want, you can mix it in.

Our favourite is Rocco & Roxie Litter Box Odour Eliminator. You could also use baking soda to reduce smells. While it doesn’t work quite as well, but it will reduce smells.

rocco & roxie litter box odour eliminator

Rocco & Roxie Litter Box Odour Eliminator: Our Favourite

4.1 out of 5.0 stars (4.1)

Rocco & Roxie Litter Box Odour Eliminator uses essential oils to neutralize odours. We also found a bottle lasted for ages.

11. If You Have An Enclosed Litter Box, Replace the Filter Often

If you use a hooded or enclosed litter box or a self cleaning litter box, make sure you replace the filter at least every three months.

If your cats share the litter box, replace the filter every 8 weeks. 

The type and brand of litter box you own will dictate the size and shape of filter. As such, we can’t recommend any one product. So, have a look on Amazon for the best ones for your particular litter box.

12. Use an Air Purifier

While they’re the most expensive option on this list, air purifiers are brilliant at removing cat litter stink.

They physically remove the pollutants in the air that cause smells.

Our favourite is the Levoit Pet Air Purifier. It removes 99.97% of smells and odours. It also removed pet dander, pollen and mould spores. It won’t break the bank either.

Levoit Pet Air Purifier: Excellent at Removing Ammonia Smells

4.5 out of 5.0 stars (4.5)

The Levoit Pet air purifier removed 99.97% of smells and pet hair. It’s perfect for removing the nasty smells of the litter box.

In Conclusion

The stinky smell of ammonia in litter boxes is one of the worst things about owning a cat.

If your litter box smells like ammonia, don’t worry. There are plenty of things you can do to reduce, even get rid of the problem altogether.

Some are simple changes that won’t cost you a penny. Others might cost you a little bit of money. That said, ammonia stinks and it can have health impacts, both on you and your pet. So, if you do have to spend a bit, it’s money well spent.

Photo of author

Ben Doyle

Ben Doyle co-owns Pet Checkers with his wife, Vicki. He spends his days looking after all kinds of animals, from dogs to eagles. When he's not taking care of animals, he's writing about them.

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