Does Rat Pee Smell? Facts and Tips

Does rat pee smell - white pet rat in a cage

For all owners of pet rats you are going to be involved with rat pee right from the get-go. But what are the main issues when dealing with rat pee? The most common questions I’ve heard is ‘Does rat pee smell’. Well, having owned a rat for the last six years, I can categorically tell you the answer…

Rat pee does smell. It can smell a lot if the cage is not cleaned often enough. Rats rely on us to clear away their pee, because it is dangerous for their skin and their habitat if left too long. The acid in rats’ pee can burn their skin and cause all sorts of issues in the long term.

Consistent cleaning of rat pee is really important to keep your pet smelling fresh, and keeping them healthy.

But why is rat pee so smelly? And what are the best tips for dealing with it?

In this article I’m going to answer all the most burning facts about rat pee, how smelly it is, and then lots of top tips for dealing with it successfully.

Facts, Why is Rat Pee So Smelly?

The main reason rat pee smells is because it is a mix of urea and water, it can also contain ammonia and calcium. You might see where your rat has urinated by the faint chalky texture left behind. This is calcium. Ammonia has quite a strong and distinct smell, and if left, can become very pungent. 

Strong smelling cages are also not good for your rat’s health for various reasons. Smelly cages are not that good for the owner either!

Keeping your cage fresh and clean is important, but try not to become obsessive about it. It is a fine balance because rats, like all animals, function on smell. They enjoy the smells of their friends, they enjoy the smells of you, and they also enjoy the smell of home. If you disrupt this too much, it can disorientate them. Smell is a kind of sight to rats, just like feeling with their whiskers is. 

Now that we know rat pee smells what do we do? 

Here are Some Tips

The first thing to consider when you buy a rats cage is to get a large cage. Always err on the side of larger than smaller. Particularly if you have more than one rat. It is common to get two rats at once, rats love company. Two is a good number, as they will bond and live together well. Only on very rare occasions will rats become aggressive with one another. 

Start with a Good Cage

Once you have a sizeable cage, it is advisable to put a bit of thought into how they will live happily in the cage. For example, putting up sleeping hammocks is not only fun and interesting, but it also helps to keep your rats away from sleeping next to urine, which is not good for them. Make sure the cage is easy to clean. 

Get a Good Substrate 

You should get a good substrate for your rat’s cage. This will help soak up urine and the subsequent smells that come along with it. 

Don’t be tempted to put perfumed paper down or anything that will interfere with your rat’s natural processes of getting about. Remember, rats use their whiskers by whiskering, coupled with their sense of smell to get around. 

Perfume is unnecessary and can not only cause problems, but also is hopeless in covering up the very strong smell of rats urine. 

Good substrate absorbs smells, but does no harm to your rat, this includes removing choking hazards. The wrong substrate could get stuck in their gut. 

Before buying substrate look at a few different options.

Some options for bedding include.

Paper Pellet Bedding 

There are no two paper pellet beddings alike! So you’ll have to do a bit of homework on this one. The basic principle is that the pellets will absorb the urine, and the cheaper varieties, although very good, will turn to mush. The more expensive varieties won’t be quite so mushy. So it is all a matter of budget and time, consider this before you choose.

The great thing about paper pellets is that you can clean them as you go. So you might spot a soiled area, and then just remove that area, then add a few more pellets. They are usually of a size that rats won’t try to nibble on.  This is important because if they are the wrong size, a rat can choke on them. 

Always Be Aware that Rats Need to Chew a Lot 

Rats continuously grow their teeth, which is handy! But the result is that they have to be constantly filed down. This gives them the need to nibble constantly, and if they have no chew toys, then substrates could be an option for them, which is not a good thing. Ensuring you have the correct substrate and chew toys is the solution.  Pellet bedding, if made by a reputable company, will be safe for your rat. They are very easy to use and don’t have a lot of dust as some substrates do. 

You can also purchase the variety that is more affordable for you once you have checked out that they are a reputable pet rat supplier. 

Make Your Own Paper Bedding 

This is also a popular option, some pet owners will alternate between the two or use both depending on their needs. 

Like pellets, not all paper bedding is alike. 

Some paper toweling is of better quality than others. Generally, it is better to stick with a high absorbent toweling, that is not perfumed or inked.

This way you can go to town with the bedding, allowing your rat to not only be safe from toxic pee build-up, but also allow them to use it for nesting and sleeping. Paper toweling also turns a bit mushy when covered in rats pee and you’d simply remove the area or just add new towels to the entire cage as it is very affordable.  It’s pretty easy to set up too, just by tearing strips of toweling and placing them in his cage. Some paper towels are so absorbent they can last a fair amount of time. 

Creating substrate or bedding for your rat is highly personal. Some people swear by old newspapers, and in years gone by this was often used. If you want to use old newspapers, then check that the ink is not toxic. Another thought is that if your rats are white, some newer ink will dirty his white fur!

Does rat pee smell - black rat on a log outside

Using Cloth or Fleece 

Using cloth, small carpets or even fleece could work for your pet rats cage, but one thing to keep in mind is that they need daily cleaning. 

I would not use them, but that is just my take on it. Many owners enjoy using cloth and wash them daily. If you do go this route, then make sure they are washed and thoroughly dry. If they are even slightly damp, mildew and mold can build up.  I have been known to place a tiny square of fleece in their sleeping hammock in the winter, but as for use for urine clean up, I don’t feel this is the best method.

Even using fleece in a bedding area comes with its own hazards, as rats that are not litter trained will just pee on them as they sleep! Generally, they keep very warm in regular bedding, and also by cuddling up to their pals, which they love to do. 

Using Hemp to Soak Up Smelly Urine 

Hemp is a great alternative simply because it is non-toxic for rats. It also soaks up to 4 times its size in fluids and would work in the same way as pellets.

 It is often best to go and shop for different substrates to get an idea of what is out there and what is on offer. Some people love hemp because of the absorbancy factor and the natural base it is made from 

Also, because it is so absorbent, the likelihood of your rat coming into contact with rats pee is highly reduced. 

Aspen Bedding 

Aspen type bedding is touted as being the best bedding to reduce the odor of rat urine. This odor can be bothersome to some rat owners, and if you have more than one rat, the build-up is pretty substantial. Aspen bedding absorbs odors and if correctly manufactured by a reputable pet supplier, can work very well. Some of them have built-in fragrances that are animal friendly, like the smell of birthday cake. Some people will love this, rats can handle it, but many prefer a natural, clean smelling cage. 

As you can see there are so many options and only a few of them mentioned here. 

Another way to handle the toxic properties of pee and also the smell build-up is to keep your rat’s cage clean, which you should be doing anyway. [Source]

Tips and Tricks for Cleaning Rat’s Cages 

You might find it invaluable to buy a smaller cage or some sort of holding area for your rats when you clean out their cage. This way you can empty it well and give it a good scrub if need be. If you are doing it enough times, you shouldn’t need to scrub, but you will need to air the cage before you put your rats back inside. 

Here are some tips for good cage cleaners, getting rid of urine build up and smell. [Source]

Vinegar and Water Mixture 

Just simple household vinegar works well for this. I use white vinegar as it just looks better than the darker one. You can use pure vinegar, but you can also mix one part vinegar to one part water, depending on the amount of staining or soiled areas they are.

 You would have separated your rats from the cage so that the smell does not disturb them. Vinegar is good on so many levels. It’s inexpensive, it cleans well, it kills off many bacteria and also the acetic acid in vinegar neutralizes the urea smell in rats pee. I pop it into the sun to dry after the clean, or use paper towels to dry it off and leave it for a while before I reintroduce the rats back into their home. 

Baking Soda 

Some people place a fine layer of baking soda into the cage to cut down on smells. I find that having the correct substrate means you’d probably not need to do this. I have used baking soda to clean the cage. Just sprinkle it down and allow it to absorb the smell. Then turn the cage upside over a trash can. There go the smelly particles into the trash. You can then rinse with the vinegar mixture mentioned above. 

Store-Bought Cleaners 

There are so many different kinds of sprays out there, and they are all really good. Just spray and wipe, and you are done. So, although I do like the home cupboard methods, for ease I also like the prepared sprays. They contain disinfectant that is not toxic to rats, and strong cleaners inside the ingredients to get any soiling off quickly. 

Another Great Tip for Homemade Sprays 

If you do go the store cupboard method of using vinegar, and this does work well, you can buy a plastic bottle with a nozzle spray attachment. This way, the product is easy to use. You can also spray into corners to get into tricky places. 

Remember don’t clean the cage too often, you will find a ‘happy medium’ over time. Once a week does for most cages, but cages can be quite full or fairly empty. So each has its own requirements. 


Rats pee is smelly, but so would our pee stink if we didn’t have a toilet. As rat owners, we need to focus on the best methods we can to keep their cages hygienic and clean. 

This will include good bedding that is safe for rats. 

Some bedding options will cost you very little and work quite well. Other methods you might prefer are premade substrates that are designed for rats. They hold smell well, as well as moisture. You don’t want the acids in rats urine to be near their skin for too long. 

Try and separate areas for sleeping and eating, for example, it can cut down on the amount of urine in certain areas. 

If you can’t control that, don’t panic. Giving the cage a good regular clean with either store-bought cleaner or homemade cleaner with vinegar works well coupled with the correct substrates, but you have to be consistent. If you have a well-kept rat enclosure, you will not have issues with your rat’s health farther down the line. 

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