Have you noticed your cat litter box has become smelly over time? Despite how regularly you clean the box, odors and bacteria can build up in the base over time. Plastic litter boxes are especially problematic because plastic absorbs odors and stains.
What’s more plastic litter trays can become easily scratched, especially if you have a cat that loves to dig around in their tray. These grooves then act as the perfect breeding ground for germs and bad bacteria, making the litter box less hygienic and capturing even more nasty smells.
One solution to this is to opt for a stainless steel litter box. Not only are metal boxes more durable and long-lasting, but steel also won’t absorb any odors and is a scratch-resistant material. Plus, they’re easier to clean!
If you’re thinking of purchasing a metal litter box to get all these benefits and more, then you’re in luck! I have reviewed the best stainless steel litter boxes available so that you can choose the right product the first time around.
My Top Pick
iPrimio Ultimate Stainless Steel XL Litter Box
The best stainless steel cat litter box has to be the iPrimio Ultimate XL Litter Box.
It is the only product available that comes with a detachable enclosure, helping to contain all mess from kicking litter and spraying. What’s more, it also has rounded corners for safety, is easy to wipe clean, and is designed to last a lifetime!
You’ll find a full review of this product further down the article, along with some other great alternative products to choose from.
Best Stainless Steel Cat Litter Boxes
Before I go through my top-rated products, there’s one important question we need to answer: What features are important when considering which metal litter box to buy? Here are some of the things I wanted to see on my search.
- Large Size: The number one reason why cats don’t use their litter tray is that it is too small. Therefore, the ideal stainless steel litter box is large enough for your cat to comfortably turn around in. If you have a large breed such as a Maine Coon, this is even more essential.
- Easy to Clean: Cleaning your cat’s litter box is never going to be a fun task, however, the perfect litter box makes cleaning as simple as possible! So, a stainless steel litter box that makes both daily scooping and weekly cleaning easy is a must.
- Safety-Frist Design: Metal can have sharp edges, which can cause harm to both you and your cat. These issues can be avoided completely by choosing a stainless steel litter box that has rounded edges and corners, which was also a must-have for me.
- Reduces Mess: My cats love to kick their litter outside of their tray and make a mess, so I was searching for a high sided stainless steel litter box to help contain mess inside the tray.
With all these factors taken into consideration, here are the best stainless steel cat litter boxes available right now.
1. iPrimio Ultimate Stainless Steel Cat XL Litter Box (Best All-Rounder)
Firstly, this is a high sided litter box, that is comprised of a litter pan and a detachable enclosure. The pan itself is 6 inches deep and the enclosure adds a further 6 inches, meaning if your cat wants to kick any litter out the tray, they’ve got 12 inches to go! Even the entrance of the tray is 6 inches tall, which really helps to keep mess to an absolute minimum.
As well as being generous in height, this pan is also large in both length and width, measuring 15.5 inches by 23.5 inches. This should be big enough for even large cats to use comfortably, and it’s the perfect size for my Maine Coon.
This litter tray is also extremely easy to clean. There is a non-stick coating on the surface which helps to prevent any clumps of wet litter from sticking, and as the metal is scratch-resistant it is simple to clean by simply wiping. Plus, the stainless steel material won’t absorb any odors while the open design stops any smells from being trapped and becoming concentrated.
I also love the rounded corners of this litter tray, meaning no awkward corners to get into while cleaning. Besides, this also means there are no sharp edges, ensuring your feline won’t get hurt on the corners of the box, and neither will you. All in all, I love this litter box!
- High sided cat litter box, ideal for containing mess
- Enclosure and litter pan together come to 12 inches tall
- Big enough for even large breeds to use comfortably
- Non-stick coating for easy cleaning
- No sharp corners to keep your kitty safe from harm
- Won’t absorb any odors and is 100% rust-free
- Too large for kittens to use
2. MEEXPAWS Extra Large Stainless Steel Litter Box for Cats (Best for Spraying Cats)
If you have a high spraying cat, you should try the MEEXPAWS Extra Large Litter Box for Cats.
This litter box is only 5.9 inches tall, making it the shallowest on this list, but it does come with a corner splash guard to protect against splashes. Unfortunately, this does only cover two of the sides of the litter box, but still offers pretty good protection against splashing and spraying.
Also, this litter box comes with a litter mat. While you can easily purchase a litter mat separately, it is super convenient that one is included. Litter mats are great at preventing litter tracking and removing litter particles from your cat’s fur once they’ve finished using their tray. Plus, a metal litter scoop is also included!
I also rate that this litter box is extra-large, measuring 23.6 inches by 15.7 inches. This is the one of the largest stainless steel litter boxes available on the market and is suitable for all breeds! As this litter box is made from metal, it also has the host of benefits that comes with it, including not absorbing any odors, being easy to clean, and lasting a lifetime.
- Comes complete with a spray guard, litter mat, and metal scoop
- Large stainless steel litter tray
- Suitable for all different domestic cat breeds
- Won’t absorb odors and is rust-free
- Non-stick and easy to clean
- Splash guard only protects two sides from spraying
- Unprotected sides are only 5.9 inches high, lower than most other products
3. Yangbaga Stainless Steel Litter Box for Cats (Non-Slip Design)
Another great product is the Yangbaga Litter Box.
This is also a great litter box for messy cats as it is 8 inches tall on every side. While this high entry point does make it difficult for kittens and senior cats with mobility problems to enter and exit the tray, it is great for any cats that love digging and kicking.
Also, rather than the high sides attaching to the litter box as an enclosure, this metal litter box is just one extremely deep tray. When it comes to cleaning, this makes things much easier as you don’t need to worry about any urine escaping through the gap where the two halves of the litter box join. It’s also great for cats that love the spray for the same reason!
I also love that the litter box comes in two sizes, meaning you have a choice of which to buy depending on the size and breed of your cat.
This litter box also has smooth edges and corners all the way around, making it safer for your cat and also easier for you to pick up and handle comfortably without hurting your hands. Once again, these rounded corners also make cleaning easy, further enhanced by the easy-wipe and scratch-resistant surface.
Lastly, this litter box also has four rubber feet on the base which makes the tray non-slip. While full litter boxes are heavy and unlikely to move around your floor during use, these feet are super helpful when it comes to refilling the litter tray after cleaning. Besides, they also help protect your floors from scratches.
- Available in two different sizes to suit a range of breeds
- 8 inches tall to contain mess from kicking litter and spraying
- One deep tray so no leakage points
- Rounded corners for your comfort and your cat’s safety
- Scratch-resistant and easy-wipe
- Non-slip base to prevent the litter box moving when refilling
- Not suitable for kittens or senior cats
4. Ohmaker’s Stainless Steel Cat Litter Box (Charity Donations with Each Purchase)
Want an incredible litter box that also helps support cat charities? You’re in luck! Try Ohmaker’s Steel Cat Litter Box. The company donates to the MEOW Foundation, a cat-focused charity, with each and every purchase!
This litter tray is also great for all cat breeds as it measures 23.5 inches by 15.5 inches. However, the sides are only 6 inches high. While this will contain some mess, if you have a cat that loves to dig in their litter or that sprays, you’re better suited to a litter box with more protection.
That being said, the litter box is non-stick and made completely from stainless steel, so cleaning is easy, further helped by the rounded edges. These edges also help to protect your cat from harm and make carrying the litter box more comfortable on your hands; it is clear the manufacturers have your and your cat’s safety in mind.
Once again, as a stainless steel litter box, you’ll also benefit from no rust, no absorption of odors, and no staining. Plus, being durable it is the only litter box you’ll ever need, which is great for the environment.
- The company donates to the MEOW Foundation with every purchase
- Suitable for even large breeds
- Non-stick surface for super easy cleaning
- Does not absorb odors and is rust-free
- The sides are only 6 inches high so won’t contain all mess
5. VehiGo Extra Large Stainless Steel Cat Litter Box (Best for Large Breeds)
Another great option is the VehiGo Extra Large Litter Box.
As with the other metal litter boxes on this list, the material means that this litter tray is scratch-resistant and won’t absorb any odors. It is also durable yet lightweight, and won’t rust over time. All these features make it safe for your cat, good for the planet, and easy to clean. Win-win!
This is also an extra large stainless steel cat litter box, and the largest product available. Its dimensions are 23.6 inches by 15.7 inches, large enough for all breeds. However, despite being the largest in terms of length and width, it is the shortest by height, sitting at only 5.9 inches tall. Because of this, I would recommend choosing a high sided cat stainless steel cat litter box instead if you have a messy cat.
This litter box is also easy to clean, which is a plus. The surface is non-stick, smooth, and can simply be wiped. The corners are also rounded meaning you won’t be struggling to clean the corners. Besides, the entire tray has no sharp edges to ensure the safety of you and your cat.
- Largest stainless steel litter box available
- Suitable for all domestic cat breeds
- Non-stick surface and rounded corners make cleaning easy
- No sharp edges for your and your cat’s safety
- Made entirely from long-lasting and durable stainless steel
- Shallowest litter box measuring 5.9 inches tall
- Not ideal if you have a messy cat
6. EXPAWLORER Stainless Steel Large Cat Litter Box (Best Budget Buy)
These litter boxes last a lifetime and so they don’t come cheap. Therefore, if you’re budget is tight, try the EXPAWLORER Stainless Steel Large Cat Litter Box.
Firstly, thanks to this metal litter box being made from 100% stainless steel, it will not absorb any odors or stains and is also rust-free. This means this metal cat litter box will be effective in reducing unwanted odors while being durable enough to last a lifetime.
You’ll also notice this litter box has relatively high sides, measuring 6 inches. While this is not as tall as some other products and isn’t effective again sprayers or cats that love kicking their litter around, it will help contain most mess. However, the length and width of the litter box are slightly disappointing. Despite calling themselves a “large” litter box, the tray only measures 21 inches by 12 inches, which is too small for large breeds.
That being said, there’s still plenty to love. The box is easy to clean thanks to it being made from metal and the rounded corners mean there are no hard-to-reach places. Also, the rounded edges around the top of the box mean it is comfortable in your hands when being held and won’t hurt your furry friend either!
- Rounded corners to protect your hands and your feline
- Effective odor control
- Easy to wipe clean and won’t absorb odors or stains
- Durable and 100% rust-free
- Not suitable for large breeds
- The sides are only 6 inches high so won’t contain all mess
7. iPrimio Cat Metal Litter Box (Best for Easy Cleaning)
All stainless steel cat litter boxes are easier to clean than their plastic counterparts. And the iPrimio metal litter pan is no different. It is rust-resistant, doesn’t hold odors, and never stains – no matter how much your cat uses it.
However, the iPrimio metal liter pan takes things to the next level. The entire inside of the tray is lined with a black non-stick surface. It’s extremely easy to wipe clean and ensures no residue is collected. The black color also makes it easier to see residue so you can make sure you wipe it all away each time.
Additionally, the inside corners of the pan are slightly curved, so most scooper edges and the litter pan fit together perfectly. By limiting gaps between the pan and litter scooper, it is easier to clean the tray. You can even purchase the iPrimio Non-Stick Deep Shovel Sifter Scoop if you want the perfect fit!
The outside edges of the pan are also curved so they won’t hurt your hands or your cat. Plus, non-slip rubber feet ensure your cat doesn’t push the tray around while doing its business. Not only does this help to reduce mess, but also ensures the tray won’t scratch your floors.
The dimensions of the tray also make it suitable for most cats. It is extra-large in size, measuring 23.5 inches by 15 inches. This is plenty big enough for cats of all shapes and sizes. The walls measure 6 inches high though and some mess might be kicked outside the tray.
- Perfect for cats of all sizes
- Black non-stick coating for easy cleaning
- No gaps between the litter tray and scoop
- Resistant to rust, stains, and odors
- Non-slip feet so no scratched floors
- Rounded, easy-to-grip edges
- 6-inch sides which might not contain all mess
8. KUNWU Stainless Steel Cat Litter Box (Best for Kittens)
If you have just adopted a tiny new kitten or taken in a little stray cat, this litter box from KUNWU is going to be ideal. It goes without saying that kittens are a lot smaller than fully-grown adult cats. Therefore, they need a smaller litter tray with lower sides they can easily climb in and out of.
This KUNWU litter box comes in multiple sizes, including one measuring only 2.75 inches deep. While this isn’t going to be the neatest litter box for kicking and spraying adult cats, it is the ideal height for kittens. Their little legs can easily climb over the sides so they can learn to use their litter tray with ease.
The low sides of this tray might also be useful if you have an older cat with mobility issues. Their swollen joints might make it harder for them to get in and out of a regular-sized tray. Or, if you do have a bigger cat, you can purchase one with taller sides. The same litter pan comes with a depth of 4 inches, 6 inches, or 8 inches, so choose the option right for your cat.
Of course, this litter box is made from stainless steel and so it is strong and durable. It is also resistant to rust, staining, scratching, and retaining odors. Furthermore, it features rounded edges so you can carry the litter tray with ease. This is also a must-have when kittens are using it, so they don’t hurt themselves on any sharp corners.
- 2.75 inches high so perfect for kittens to use
- Available in multiple depths for other cats, too
- Resistant to rusting, staining, and odors
- Rounded corners for added safety and comfort
- Low sided version won’t contain mess well
- Expensive compared to some other products
- No non-slip feet so could move around the floor
9. Kichwit Stainless Steel Cat Litter Box (Best for Small Apartments)
Finally, we have this stainless steel cat litter box from Kichwit. This is a smaller litter tray and so won’t be suitable for large breeds at all. However, its compact size means it is an excellent option for anyone limited on space. Measuring only 21.1 inches long and 13.1 inches wide, it’s great for small apartments.
Despite its small dimensions, it still measures a reasonable 5.9 inches tall. If you have a cat that loves to kick litter everywhere or spray urine, this won’t do a good job at containing the mess. But for the average cat, it’s pretty reasonable considering its smaller length and width.
Being made from stainless steel, the litter box is extremely durable. The material is rust-resistant, won’t hold onto any odors, and doesn’t stain. The surface isn’t easily scratched either, so it’s a much more hygienic option with no nasty bacteria lurking in the tiny grooves.
Additionally, the litter box features rounded edges that are comfortable to hold and safer for your cat. With non-slip feet to prevent movement, easy cleaning, and a simple design, there is plenty to love!
- Smaller dimensions perfect for apartments
- Decent height considering the width and depth
- Durable and won’t scratch easily
- Resistant to odors, stains, and rust
- Rounded corners for comfort and safety
- Too small for larger breeds of cats
- No ideal for messy kickers and sprayers
Stainless Steel Cat Litter Box Buying Guide
While these are the best stainless steel cat litter boxes available right now, you need to choose the one that is right for you and your cat. To help you decide, I have made this handy buying guide which you can follow.
Correct Size Litter Box
The size of the litter box is arguably the most important consideration. Too small and it may be uncomfortable for your cat to use, which could result in them not using it altogether! But too large is equally as problematic. A tray that is too big can make a cat feel unsafe and vulnerable while it does its business. It might find somewhere better to go instead!
As a general rule of thumb, your cat’s litter box should be 1.5x the length of their body, not including their tail. This gives your cat enough space to move around without feeling restricted while ensuring they still feel enclosed and safe when going to the bathroom.
The largest stainless steel litter box available is 23.6 inches long, which is an extra-large litter box for big breeds, whereas smaller cats could be better suited to a smaller tray. Base the litter box you buy on the size and breed of your cat for guaranteed success. When purchasing a litter tray for kittens, consider how big your cat will be when fully grown and accept you might have to upgrade their tray as they grow.
Height of the Litter Box
Height is another important consideration. Firstly, the higher the sides of the litter box, the more mess it will be able to contain. This means that a high sided design is the best for messy cats, as any litter kicked about will be contained. Hooded designs or those with an added enclosure are a must for the messiest cats or those that spray urine.
However, you also need to consider how your cat will get in and out of its litter box. Whereas high entry points are great at containing mess, senior cats or kittens will struggle to enter and exit the litter box. Therefore, these cats are better suited to a design with lower sides, or at least a lower entry.
If you’re dealing with a messy but immobile cat, consider their comfort as a priority and opt for an easy-access tray. You will have to help contain any mess they make in other ways. For example, purchasing a litter mat to collect any litter that’s kicked outside the tray, or using a splash guard to contain urine without impacting comfort.
The corners of metal litter boxes can be sharp, acting as a potential hazard for your cat. These sharp edges can also dig into your hands when you’re carrying or moving the litter box around, so you should always opt for a stainless steel litter box that has rounded edges. This will help to keep you and your cat safe from harm.
Non-slip rubber feet are another good feature for your litter box. Litter boxes, especially those made from stainless steel, are prone to slipping around on hard floors. This can scratch and damage the floors, as well as make a mess if your cat accidentally tips over the tray. Non-slip feet prevent this from happening.
Easy to Clean
It goes without saying that no owner enjoys cleaning out their cat’s litter box. However, choosing a litter box that has no tight corners where dirt can get lodged can make this easier, so ideally you want your litter box to have this feature. The closer the litter scoop can get to the surface of the tray, the easier is it to keep clean.
Steel is already a good material when it comes to cleaning as it won’t hold onto odors, is resistant to scratching, and easily wipes clean. They’re also resistant to rusting and won’t stain like their plastic counterparts. However, if you want to make cleaning even easier, select a litter box that has a non-stick coating too. This makes wiping away all residue even more of a breeze!
Stainless Steel Cat Litter Boxes vs Plastic Litter Boxes
Most cat owners have a plastic litter box, which does do the job. However, stainless steel litter boxes come with many additional advantages. Here are the pros and cons of metal litter boxes and why you should consider making the switch.
Stainless Steel Litter Box Pros
- Sturdy & Durable: Stainless steel is a much sturdier material than plastic, meaning moving the litter box is easy. Also, it won’t morph shape over time, is resistant to rust, and is a much more durable material. If you buy a stainless steel litter box, it’s likely to be the only litter box you’ll ever need.
- Easier to Clean: Metal is also a lot easier to clean than plastic. It is resistant to scratches meaning its surface remains smooth even after it has been in use for some time, so you can simply wipe any germs, bacteria, and dirt from the surface. Many models also have non-stick coatings for an even easier clean-up.
- Doesn’t Absorb Odors: Stainless steel also doesn’t hold onto odors the same way that plastic does. Whereas over the years your plastic litter box may start to smell despite being recently cleaned, a stainless steel litter box will remain odor-free throughout its lifetime.
- Will Not Stain: As well as not holding onto odors, metal cat litter boxes also won’t become stained over time. This is not only a benefit aesthetically, but also shows that the material is not holding onto nasty germs and bacteria.
- More Hygienic: Plastic, especially plastic that becomes scratched and has grooves on its surface, is a breeding ground for germs and bad bacteria. As metal is a scratch-resistant material, it won’t harbor these potentially dangerous pathogens and is a much more hygienic option. This makes the litter box safer for you and your cat, who are less likely to pick up these bad germs.
- Eco-Friendly Option: As steel litter boxes are designed to last forever, they are less damaging to the environment. Plus, you should look at lowering your plastic use to really benefit the planet. Swapping from a plastic litter box to a metal one is a quick and easy way to do this. Consider swapping from plastic cat bowls and litter scoops as well.
- Liked by Cats: Another huge advantage is that most cats will like using these litter boxes. Because they don’t hold onto odors and are easy to clean, cats will prefer using them to smelly old plastic litter boxes. However, make sure you get the right shape and size for your cat to reap the full rewards.
Stainless Steel Litter Box Cons
Of course, nothing comes without its disadvantages, and there are a few drawbacks to using a metal litter box.
- More Expensive: Plastic litter boxes are a cheaper alternative to stainless steel litter trays. However, as metal litter boxes are extremely durable and you won’t ever need to buy a replacement litter box, the cost is only a minor drawback. They may even work out cheaper in the long run as they tray will last you forever!
- No Enclosed Litter Boxes: There are also not as many stainless steel litter boxes available, whereas there are thousands of plastic ones. Therefore, if you are searching for a metal litter box with a lid, you’re out of luck – there are none. However, open litter boxes are generally preferred by cats, so you could always make the change.
- No Sifting Litter Boxes: You can also not find a sifting litter box for pine pellets made from metal, which can be frustrating if you use a wood pellet litter as they make daily scooping and cleaning much easier. You might consider changing cat litter to a clumping litter or sticking with a plastic sifting tray instead.
Despite these minor disadvantages, I still think the benefits of a stainless steel litter box outweigh the cons. However, they aren’t for everyone, so do some research to discover what is the best litter box for you and your cat.
DIY Stainless Steel Cat Litter Box
Alongside all the great products I mentioned, you can also make a stainless steel cat litter box easily at home, which can end up being a less expensive alternative but one that is just as effective. As it is still made from steel, you will still get all the benefits, just without the hefty price tag.
Therefore, a DIY stainless steel cat litter box is a great option for any cat owner who is deterred by the price. It is also especially useful for owners of more than one cat, owners of cat shelters, or breeders, as forking out on several metal litter boxes at once will be expensive.
Thankfully, they’re really easy to make in just two simple steps:
- Find a large stainless steel pan that is at least 6 inches deep and is the right dimensions to make a good litter tray for your cat. You can usually get these from restaurant supply stores at a much more affordable price than a pet store.
- Use duct tape to cover all the edges of the steel pan. This will effectively smooth the edges of the box, as those not intended for use as a litter tray will often not be rounded. However, duct tape is effective in making the DIY stainless steel litter box safer for your feline.
If you want the litter box to have higher sides, you could place the finished tray inside a tall cardboard box. However, this is only advised if you are trying to prevent mess from kicking litter over the edges of the tray – if you have a high spraying cat, you’ll just end up with a soggy cardboard mess which isn’t ideal!
Q: Are stainless steel litter boxes better than plastic?
A: Both stainless steel litter boxes and plastic ones have their advantages and disadvantages. However, steel boxes are more hygienic, easier to clean, won’t absorb odors, and are designed to last a lifetime. Therefore, yes, I believe stainless steel litter boxes are better.
Q: Do cats like stainless steel litter boxes?
A: Cats hate a smelly litter box, and as metal litter boxes won’t absorb any odors, your cat will likely appreciate it! In fact, many cats love metal litter boxes for this reason. However, the litter box still needs to be the right size for your cat for them to like it.
Q: What type of litter box is best for the environment?
A: If you want an eco-friendly cat litter box, any non-plastic litter box is best. There are a few bamboo litter boxes on the market, however, the general consensus is that stainless steel litter boxes are best for the planet as they are long-lasting and durable.
Q: What is the best stainless steel cat litter box?
A: In my opinion, iPrimio Ultimate Stainless Steel Cat XL Litter Box. It has high sides to contain mess, is large enough for all cat breeds, is easy to clean, and is designed to last forever.
Q: Is there a stainless steel cat litter box with a lid available to buy?
A: No, there are no enclosed metal litter boxes available on the market. However, the iPrimio Ultimate XL Litter Box has a detachable enclosure, designed to add height to the metal pan and contain mess.
Q: What are the benefits of a stainless steel litter box?
A: They are durable, don’t absorb any odors, are easier to clean, and are a great eco-friendly option.
Q: What are the disadvantages of a stainless steel litter box?
A: The only disadvantage is that they are more expensive. However, they are designed to be long-lasting, so this is not a major issue. Also, they don’t come with a lid nor as a sifting litter box which may deter some owners from purchasing one.
MY FINAL THOUGHTS
I think stainless steel litter boxes are a great option. They provide a long-lasting solution as they are durable, resistant to rust, and won’t absorb smells over time. Add the fact that they’re easy to clean and environmentally friendly and it is hard to understand why these litter boxes are not more popular!
If you’re looking to upgrade your plastic litter box to a stainless steel one, these reviews will help you to find a product that’s perfect for you and your cat. Remember, the size of the litter box and the height of the sides are both crucial considerations when selecting a product, but get this right and you’ll start reaping the rewards.
j. markussen says
Really glad I ran across the info you have supplied. I have 2 manx cats (20 yrs old now) & have had issues in the past, but nothing like I’m having now. We have had (3) litter robots, 2 of which are still working & the newest version litter robot III has a heavy duty rubber material that litter sticks to really bad & over time the rubber starts smelling & the cats object. I now have the 2 litter robots, & 1 of the highest rated plastic models, the ex-lrg cattit & 4 other plastic models & 1 larger one out on their kitty playground, I believe that adds up to (9)!! yikes!, (3) are located out in their play area (which we use litter in) & (4) are located in our entry way (can’t use the front door anymore) the cattit is in the living room & then (1) litter robot in the shower in the back bathroom. all of the inside boxes except the robot we have been using the pet pads in in order to try to keep them all clean all the time. So, my male cat comes in after a leisurely time out on their deck & immediately pees on our wood flooring (he has damaged it to the point that we will have to replace a hefty portion of it). So, that’s the peeing issue part of this insane story. The next part is the pooping, which both cats do in the living room despite all of our efforts with all the f’ing litter boxes. Kind of my wit’s end at this point when I started researching again about this issue. This time I thought it’s not the litter or the kind of litter or the pads, it’s the boxes themselves that are retaining the awful urine smell. Very long story short (sorry), I queried metal boxes & found your article which confirmed my thought that metal can’t absorb odors like plastic does. Eureka!! I’m going to buy a couple of the stainless steel ones that you recommended & discontinue use of the plastic ones. I will follow up on this site & let you know if it works. If it does, you just saved me from the funny farm!! My thanks to you!