The 5 best cat litters in 2021

Our methodology

Testing cat litters for this guide was done in two phases: a pre-cat phase and a cat phase. In the first phase, I compared litters belonging to the same category in heats of four at a time, assessing them for a variety of factors, including clumping ability, dustiness, scent, and texture.

The top two litters in each heat went on to the next phase. The litter was poured into a litter pan for the cats to use for anywhere from one to four weeks to test for odor control and tracking. Litters that were tested for two weeks or less were those that my cats refused to use, or those we tested prior to receiving the bulk of the litters for this guide. For each litter, I assessed the following qualities:

Litter weight, shape, and softness: Because cats typically prefer a soft, grainy substrate that is easy to dig, I evaluated the shape, texture, softness, and density of each litter. I measured 1/4 cup of each on a kitchen scale to compare their weights side by side.

Dust and scent: Cats are sensitive to both dust and scent, so I measured the relative intensity of each. I noted the amount of dust emitted when pouring and scooping the litter, as well as how much peppered the sides of the bowl or litter box. With scent, I went by the advice of Dr. Catherine Tannert, co-medical director of VCA Old Marple Animal Hospital, in Springfield, Pennsylvania, who said, “Cats prefer unscented litter to the cloying smell of kitty litters that are developed for the owner’s perception of cleanliness.” I did a sniff test of each litter in both phases of testing, including the thankless job of lifting clumps of litter to my nose to gauge how much of an ammonia scent they emitted.

Clumping ability and ease of cleaning: In phase one testing, I compared a small amount of each litter in plastic bowls with slick interiors similar to a litter pan. I added 1/4 cup of water to each bowl in two separate trials to gauge how quickly and easily it was absorbed, as well as how solidly it clumped and stuck together upon scooping. At the end of both trials, I emptied each bowl to look for moisture that had escaped the clumps and adhered to the bottom of the bowl.

Odor control and tracking: The top two litters from each category went on to phase two testing in a litter box for one to four weeks. I cleaned the litter pan twice daily and swept up any tracked litter once a day, noting how easy clumps were to remove and how much ended up on the floor. A daily sniff test informed me of the extent to which odors were under control. Because my cats refused to use the paper litters, I was unable to complete a phase two test on them.

Cost: I calculated the cost per pound of each litter and compared them. With lightweight clay litters, I first calculated their weight relative to a standard clay litter and adjusted the price accordingly.

The best cat litter overall

Tidy Cats Naturally Strong Litter is a super absorbent clay-based clumping litter that does a superior job containing odors, produces very little dust, and is easy to clean.

Pros: Activated charcoal controls odors; forms tight, easy-to-clean clumps; does not contain fragrances or dyes; lightweight; produces minimal dust; has texture many cats prefer; reasonably priced

Cons: A fair amount of litter tracks outside the box

Tidy Cats Naturally Strong Litter is a dye and fragrance-free clay-based clumping litter with the grainy, sandy texture that most cats prefer, or at least tolerate well. It produces very little of the little dust that can irritate cats with sensitive respiratory systems and contains bits of activated charcoal that help control odors.

In testing, Naturally Strong absorbed liquid quickly, forming a tight clump that was easy to remove in a single piece. I also found that this litter rarely left moistened clay stuck to the interior of the litter box. Best of all, it was effective at preventing foul odors throughout our three-week testing period.

Naturally Strong is also reasonably priced, typically averaging about 16 cents more per pound than you’d pay for a 20-pound box our budget pick, Dr. Elsey’s Ultra Multi-Cat Strength Litter. Unfortunately, like most clay substrates, this litter does track a fair amount around the box — though far less than some of the lighter weight versions we tested like Tidy Cats Free and Clean Lightweight Litter.

Chewy offers the best deal on Tidy Cats Naturally Strong litter: three 13.3-pound bags for $25.99. Petco and Target also offer a 20-pound jug of Tidy Cats for $14.

The best budget cat litter

Quick-clumping Dr. Elsey’s Ultra Multi-Cat Strength Litter is a fragrance-free clay litter with good odor control and very little dust and tracking.

Pros: Tight-clumping medium-grain clay litter, unscented, very little dust, low tracking, does a fine job of controlling odors, affordable

Cons: Odors can accumulate over time

Several years ago, I switched my cat to the unscented Dr. Elsey’s Ultra Multi-Cat Strength Litter at the recommendation of a veterinary behaviorist, and I’ve been using it religiously ever since. But with the opportunity to test nine clumping clay litters for this guide, I was anxious to see how it would hold up compared to other brands. Quite well, it turns out.

For a highly affordable litter that is odor-containing and easy to clean, Dr. Elsey’s Ultra is as good as it gets. The unscented medium-grain clay litter also satisfies a cat’s need to scratch, dig, and bury their waste. Because it produces very little dust, it’s also a good choice for cats with respiratory issues.

In testing, it absorbed liquid almost instantly and clumped tightly. With a bit of heft to its grains, less litter was carried out of the box on my cats’ feet than with our top pick, Tidy Cats Naturally Strong Litter.

Although Dr. Elsey’s Ultra controls odors, it relies on 100% sodium bentonite clay to minimize odors instead of activated charcoal. I have found that if I’m lax on emptying and completely cleaning the box every couple of months, odors can begin to accumulate.

At around $0.50 per pound and sold in bags up to 40 pounds, Dr. Elsey’s is one of the top two most cost-effective brands in this guide, along with Frisco Scoopable Unscented Litter.

The best non-clumping litter

Pretty Litter‘s color-changing silica gel formula is an early warning system for detecting feline urinary health problems.

Pros: Changes colors to monitor a cat’s urinary health, made of safe silica gel, absorbs and controls odors, automatic delivery, 30-day money-back guarantee, reasonably priced, lightweight formula

Cons: Ammonia scent toward end of litter’s lifespan (around 12 days for two cats), false health readings toward end of litter’s lifespan (around 14 days for two cats)

Feline urinary tract diseases (FLUTD) such as bladder inflammation, urinary stones, or crystals are common in cats, according to Tannert. Just as common is a cat who tries to hide their pain and discomfort, making it all the more challenging to figure out if there’s a problem.

Pretty Litter takes the guesswork out of monitoring a cat’s urinary health with its color-changing silica gel litter. When a cat’s urine is too acidic, too alkaline, or contains blood, the litter changes color from a healthy yellow-green to an ominous dark yellow, blue, or red.

Both of my cats used Pretty Litter willingly, and despite its light weight, it did not stick to their feet as much as the clay litters. The litter is dust and fragrance-free, but it does have a bit of a chemical scent.

Pretty Litter does not clump. Instead, urine is absorbed into lightweight silica gel flakes made from safe naturally occurring minerals like those frequently used in medications, food, and cosmetics. The flakes have a light, sandy texture that satisfies a cat’s instinct to dig and bury their waste. Solids need to be scooped out daily.

Pretty Litter did a good job of controlling odors. I did find that the closer we got to the end of the litter’s lifespan (about two weeks for two cats), the more I noticed a slight ammonia scent.

Around that same time, the litter can also give false color readings. We had one stressful morning where one of my cat’s urine turned blue. It turned out the only thing that was wrong was that I hadn’t changed the litter fast enough.

For a single cat, a bag lasts a month before requiring changing. Pretty Litter is a subscription service priced at $22 per month for one cat. If either you or your cat isn’t a fan, the company offers a 30-day money-back guarantee. 

The best paper cat litter

Ökocat’s Non-Clumping Paper Pellet Litter is the most absorbent of all paper litters we tested and produces virtually no dust.

Pros: Made of sustainably sourced paper pellets, free of dyes and synthetic chemicals, very little dust, biodegradable, pellets are soft and less than 1 inch long, unscented

Cons: Expensive, some cats do not like using a pellet-style litter

Paper litters, most of which come in the form of small, firm pellets, can be a good substrate solution for cats that suffer from respiratory problems. Of the five paper varieties we reviewed, Ökocat’s Paper Pellet Litter performed best in my first round of testing. It absorbed liquid quickly and the paper pellets didn’t immediately fall apart.

Ökocat’s pellets were also the softest and smallest (approximately .5 to 1 inch in length) of the paper litters we tested, making them more conducive to natural scratching, digging, and burying behaviors than brands with heavier, larger pellets.

This litter does not clump. Instead, the paper pellets absorb as much liquid as they can before falling apart and turning into a sort of mulch. Scooping is only necessary for solids.

Unfortunately, because neither of my cats were willing to use the paper substrates, I can’t speak to how well Ökocat controls odors or holds up over time. However, it is clear from the weight and shape of the litter that the pellets are very low tracking compared to smaller-grained clay and natural varieties. We will be testing this litter out with some willing participants for a later update to this guide.

While Ökocat Paper Pellet Litter isn’t dust-free, it is close. The paper pellets are also biodegradable and do not have any scent. But this litter is also 35% to 60% more expensive than the other paper brands we tested. Unlike most paper litters, Ökocat uses sustainably sourced dye and white paper free of synthetic chemicals instead of recycled paper — a less environmentally friendly policy that nonetheless is likely better for sensitive cats.

The best multi-cat litter

For a natural litter that is eco-friendly, easy to clean, and odor-absorbing, World’s Best Multiple Cat Litter is an excellent option.

Pros: Made from compressed corn kernels, similar texture to clay litters, controls odors well when cleaned frequently, minimal dust, reasonably priced

Cons: Odors can build up without frequent cleaning and become more noticeable around three weeks of use by two cats

In our tests, World’s Best Multiple Cat Litter came out on top of the 12 natural litters we considered, thanks to its good clumping ability and odor control. Made from compressed corn kernels, this litter’s lightweight granules are slightly harder than the clay litters in our best overall and best budget litter categories, but they are still satisfyingly scratchable.

World’s Best absorbed liquids instantaneously to form tight, solid clumps that maintained their shape and structure on removal. Its natural corn-cereal scent controlled odors well when cleaned twice a day. However, I found if I left clumps in for a 24-hour period, the scent of ammonia became increasingly strong.

Tracking of this litter is relatively minimal — about equivalent to our top clay litter selections. This litter is also free of synthetic additives, chemicals, and fragrances and produces very minimal dust.

According to World’s Best, a 14-pound bag of Multiple Cat Litter is intended to last about a month (33 days) for two cats. However, I found that in the last few days of our three-week testing period, the remaining litter in the pan was somewhat less effective at absorbing odors than it had been in the beginning. Based on this observation, I would expect that by the end of four weeks, ammonia odors are likely to be even more noticeable. 

What else we considered

Clumping clay litters we liked

• Cat’s Pride Unscented Natural Care Multi-Cat Clumping Litter: This affordable clay litter absorbed liquids instantaneously and formed clumps that were only a little more likely to break apart during cleaning than our top picks. Cat’s Pride is lighter weight than most clay litters, but that also makes it more likely to be tracked than heavier formulas. For every 15-pound jug purchased, the company donates a pound of litter to an animal shelter.
• Tidy Cats Free and Clean Lightweight Litter: This Tidy Cats Litter was on par with the brand’s Naturally Strong variety, which we selected as the best litter overall for this guide. The Free and Clean litter absorbed liquids on contact, clumped tightly, controlled odors with activated charcoal, and produced very little dust. It was also significantly lighter, making it easier to carry and pour. That lighter weight, however, resulted in more tracking than the Naturally Strong litter, with granules of litter sometimes riding on my cats’ feet all the way to the living room couch.
• Frisco Scoopable Unscented Litter: Frisco’s Multi-Cat Litter is a steal. Though it is less instantaneously absorbent, forming thinner and more fragile clumps that spread more widely across the pan, Frisco’s litter controls odors as well as our top budget pick, Dr. Elsey’s Ultra Multi-Cat Strength Litter.  Unscented and among the least dusty formulas we tried, this is another great option for anyone looking to save a few bucks.

Clay clumping litters we don’t recommend

• Arm & Hammer Unscented Multi-Cat Litter: Although it is advertised as unscented, this litter has a light laundry detergent odor. And while it did form solid clumps, it was the dustiest of all of the litters we tested.
• Pioneer Pet Smart Cat Lightweight Clumping Litter: This lightweight, unscented litter absorbs liquid and clumps well, but the moisture that escaped to mix with clay at the bottom of the pan was surprisingly challenging to remove.
• Cat’s Pride Scented Bacterial Odor Control Multi-Cat Litter: Cat’s Pride Bacterial Odor Control Litter produced very little dust and clumped reasonably well, but it failed to capture all of the testing liquid, leaving wet clay stuck to the bottom of the pan. This litter has a light soapy scent.
• Arm & Hammer Cloud Control Litter: Arm & Hammer’s Cloud Control was the least absorbent litter out of the nine clay varieties we tested, although that which it did absorb clumped solidly. A heavy litter perfumed with a light laundry scent, Cloud Control is, at the very least, dust-free.

Non-clumping litter

• Petsafe Scoop Free Scented Crystal Litter: Lightly scented and with very little dust, this crystal litter absorbs moisture and captures odors. Like Pretty Litter, Petsafe’s non-clumping crystal litter is made from silica gel and a single bag lasts up to 30 days for one cat. Unlike Pretty Litter, Petsafe’s litter does not warn guardians when their pet might be experiencing urinary trouble.

Paper cat litter

• Yesterday’s News Clumping Paper Litter: The only clumping paper litter we tested, this recycled paper formula worked reasonably well to absorb moisture and form clumps. Its flaky, soft texture is also more similar to clay litter than the other varieties. Unfortunately, it was the dustiest of the bunch.
• Yesterday’s News Non-Clumping Paper Litter: Made from recycled paper, this unscented eco-friendly paper litter is absorbent and virtually dust-free. However, being made up of long, hard pellets of 1.5 to 2 inches in length, it was among the least conducive to natural scratching and covering behaviors of all the litters we tested.
• Yesterday’s News Softer Texture Paper Litter: With shorter and softer pellets than Yesterday’s News original non-clumping formula, this paper litter was the most similar to our top choice from Ökocat. With no detectable dust or added scent, the recycled paper, though eco-friendly, does contain dyes and chemicals that may cause issues for some cats. On the plus side, Yesterday’s News Softer Texture was the most affordable of the bunch, around a third of the cost of Ökocat Paper Pellet Litter.
• Frisco Paper Pellet Non-Clumping Cat Litter: Frisco’s paper litter is more or less equivalent to Yesterday’s News Non-Clumping Paper Litter at a slightly higher price. It contains baking soda for better odor control, but it is also slightly dustier with a more intense paper scent.

Natural Cat Litter

• Pioneer Pet Smart Cat Clumping Grass Litter: I really liked this grass litter because it acted almost exactly like a good clay clumping litter. The naturally wheat-cereal-scented grass particles absorbed moisture instantly and formed strong, solid clumps. Soft to the touch, essentially dust-free, and odor-trapping, the only thing keeping this litter from the top spot was its cost — almost double the equally effective World’s Best Multiple Cat Litter.
• World’s Best Original Unscented Cat Litter: Made from corn and with very little dust, World’s Best Original Cat Litter absorbed liquid moderately well and formed relatively solid clumps that were easier to remove than those belonging to Frisco Corn and Wheat.
• World’s Best Zero Mess Cat Litter: My cats and I both liked the Zero Mess formula from World’s Best, which blends the company’s typical corn kernels with additional plant fibers to absorb liquid and form tight clumps. On sniff tests, this litter also did a great job of minimizing odors. Ultimately, however, I found the Zero Mess formula to work no better than World’s Best Multiple Cat Litter, our pick for best natural litter, despite costing around 25% more.
• Frisco Corn and Wheat Cat Litter: I was disappointed by this litter’s absorbency. Not only did our tester liquid spread out within the litter, it seeped all the way to the bottom of the pan and left it wet. The clumps that did form were also quick to fall apart, making this litter more challenging to clean.
• Frisco Clumping Grass Litter: Relative to Smart Cat’s All Natural Clumping Grass Litter, Frisco’s formula did a worse job at absorbing moisture into tight clumps, making them more of a challenge to remove.
• Ökocat Super Soft Wood Litter: Of the three wood litters we tested, I liked Ökocat’s Super Soft formula best. Like the other wood litters, this version did an excellent job of absorbing liquids and preventing odors. It also had a superior clumping ability as opposed to Feline Pine and Okocat’s Original Litter — though clumping was less solid and more likely to fall apart in cleaning than some of the other natural varieties we tested. As the name suggests, this litter has softer, smaller granules than its competitors, which my cats seemed to prefer. They toileted in it a little more frequently than the others, though still not as often as the grass, walnut, or grain varieties.
• Ökocat Original Wood Clumping Litter: Ökocat’s original clumping formula is made of the same sustainably sourced wood as the Super Soft Clumping style and it absorbs moisture just as quickly. However, I found this litter’s clumping ability to be somewhat disappointing. It stuck together in some places, while in others, the wood granules quickly degraded. When dry, those same granules are quite sharp and stiff, a texture that sensitive cats may prefer to avoid.
• Feline Pine Clumping Wood Litter: Made of reclaimed lumber shavings, this was the softest of the wood litters, but it was also the dustiest. In testing, I was unimpressed with Feline Pine’s clumping ability. It absorbed moisture slowly and turned mealy like oatmeal instead of forming a solid clump.
• Littermaid Natural Premium Walnut Clumping Litter: My cats and I liked this walnut litter, which clumped tightly and controlled odors well. Because this slightly softer substrate is heavier than its competitors, it also tracked less and produced a little less dust. One thing to note about Littermaid is that it sometimes absorbs liquids slowly. The company recommends waiting a full 15 minutes after urination to scoop, but we found that often absorption took less than a minute.
• Naturally Fresh Quick-Clumping Walnut Litter: This clumping formula was my least favorite of the walnut litters we tested. It absorbed liquid well, but its clumping ability was just okay. In cleaning, many of the clumps fell apart and were more challenging to remove. It was also the dustiest of the three nut-shell varieties we tested.
• Naturally Fresh Multi-Cat Ultra Odor Control Walnut Litter: Like Naturally Fresh’s Quick-Clumping Litter, Multi-Cat is a harder, rockier substrate than Littermaid’s walnut litter and its clumping ability was fair but not great, with clumps often breaking apart in cleaning. This formula also left the most clumped litter stuck to the interior of the litter pan.

What we’re looking forward to

We’ve lined up the following litters to test for an update to this guide:

• Scoop Away Unscented Clumping Clay Cat Litter
• So Phresh Scoopable Odor-Lock Clumping Micro Crystals

 

 

What to consider when shopping for cat litter

Clumping vs. non-clumping litters: Cat litter is sold in both clumping and non-clumping formulas. Clumping formulas, including those made from clay, corn, wood, and grass, form solid masses when they encounter urine, and those must be removed from the litter daily.

Non-clumping litters absorb urine, too, but instead of forming clumps, the granules of silica, wood, or paper become saturated and gradually break down over time. On each cleaning, the substrate must be stirred to distribute the ammonia in the box. There is no difference between how non-clumping and clumping litters interact with solids — feces must still be scooped daily.

Both clumping and non-clumping litters manage bad smells. In the case of clumping formulas, urine is removed through daily scooping. In non-clumping formulas, urine accumulates in the box over time. Clumping litters can be topped off with additional litter as needed, but boxes filled with a non-clumping litter must be completely emptied and refilled after a period of two to seven weeks, depending on the brand and type of litter.

Litter texture: Litter preferences vary from cat to cat, according to Dr. Karen Sueda, veterinary behaviorist at VCA West Los Angeles Animal Hospital, but every feline wants a toileting substrate they can easily dig and cover their waste in. Cats with sensitive feet may avoid using litters with sharper granules, such as crystal or pellet formulas.

Dust-free litter: Dusty natural and clay litters can be problematic for both cat and human. Dust may cause sensitive cats, particularly those with allergies or respiratory issues like asthma, to cough, sneeze, or wheeze during or after using their litter. It can produce the same effect in humans when filling or scooping the box. While no litter is completely dust-free, those that produce very little dust are less likely to have unintended respiratory effects.

Scent-free litter: Because cats have an extremely strong sense of smell, the scent of a litter is a significant factor in whether they will use or avoid a litter box, according to Dr. Christine Calder, veterinary behaviorist at Midcoast Humane in Brunswick, Maine. Even a natural scent may deter a cat. Calder, Sueda, and Tannert all recommended sticking to an unscented variety.

Why we didn’t consider the flushability of natural cat litters: One of the purported benefits of some natural cat litter varieties is that they can be flushed in the toilet. But just because you can flush natural cat litter doesn’t mean you should, and not just because low-flush toilets and pipes made for human waste often can’t handle clumps without clogging.

Cat waste can contain Toxoplasma gondii, a parasite that causes flu-like symptoms at best and, at worst, fetal development disorders, brain damage, and premature birth in babies. Water waste treatment plants are unable to filter out this harmful parasite and it can end up in treated water that’s released back into the environment, harming fish, killing native plants, and making recreation areas unsafe. Scientific studies have found that T. gondii especially poses a threat to marine mammals like sea otters.

Types of cat litter

Clay litter

Nearly every one of the more than a dozen veterinarians, veterinary behaviorists, and cat specialists I’ve spoken to about cat toileting behavior over the last six months has agreed that most cats prefer, or are at least more tolerant of, nonperfumed clay litters. “Generally speaking, I recommend a fine-grained, clay-based clumping litter that is unscented,” said Sueda.

Most clay cat litters are made from absorbent sodium bentonite clay, a naturally occurring material acquired through strip-mining and broken down into pebble-sized granules. Some clay litters are mixed with activated charcoal for additional odor absorption. They come in both unscented and scented varieties. Traditional clay litters are also quite dusty when poured, scratched at by a cat, or cleaned, though many newer formulas produce very little dust.

Pros: Preferred or tolerated by most cats because they make practicing natural toileting behaviors like digging and covering waste easy; absorb liquids instantly and form tight clumps for easy cleaning; control odors, especially those formulas that contain activated charcoal; cost efficient; some formulas are virtually dust free

Cons: Weigh more than some other varieties of cat litter; are produced in an environmentally unfriendly way; scented formulas can be too strong for a cat’s sensitive nose; can be easily tracked out of the litter boxes, especially lighter weight formulas; some formulas are very dusty

Paper litter

For cats that suffer from respiratory problems like asthma or have recently undergone surgery, Dr. Zay Satchu, chief veterinary officer at Bond Vet, in New York City, typically recommends a paper litter, which tends to be less dusty than clay litters and less likely to stick to incision sites. Most paper litters come in pellet form and are made from either recycled materials or sustainably sourced wood. They are also almost always non-clumping with pellets that absorb liquid and slowly break apart over time. Only solids need to be scooped out of a litter box filled with paper litter.

Pros: Good for cats with respiratory problems, only solids need to be scooped from the litter box, pellet formulas are low-tracking, made from recycled or sustainably sourced materials

Cons: Some cats dislike the texture and weight of paper pellets, pellets fall apart over time, odors may increase over time as pellets become saturated with urine

Silica gel litter

Silica gel or crystal litters are made from sodium silicate sand, a naturally occurring material acquired through strip mining. They do not contain crystalline silicate or other carcinogenic materials that may be harmful to cats, but the inhalation of microscopic silica dust over time could lead to respiratory issues.

Silica gel litters are ultra-absorbent odor-eaters, but as the non-clumping granules saturate with urine over time, they may become less effective at preventing ammonia odors. Some silica litters, particularly crystal versions, may be too sharp for sensitive paws.

Pros: Made from safe, natural silica gel; ultra-absorbent and good at preventing odors; non-clumping formula does not require removal of liquids

Cons: Inhalation of silica dust over time may lead to respiratory issues, crystal formulas may be too sharp for sensitive paws, smells can worsen over time as silica gel becomes saturated with liquids, not environmentally friendly

Natural litter

Grain, grass, wood, and walnut shells are all used as alternative materials in natural cat litters. According to Satchu, not only are these biodegradable options more environmentally friendly, some have additional benefits, too. Due to their absorption ability, wood litters are typically low tracking and do a good job minimizing odors while grain litters are a safe bet for cats who like to snack on litter due to behavioral issues.

Ultimately, the superiority of one style of natural litter over another comes down to a cat’s individual preference. “I try to encourage owners to choose one litter and stick with it through kitty’s life because they are ultimately creatures of habit,” said Satchu. “Any litter that will keep kitty going where they’re supposed to be going is a good litter in my book.”

Pros: Many formulas are low dust, natural scent of some varieties controls odors without additives, biodegradable, made from sustainable materials  

Cons: Some cats may dislike the scent and/or the texture of natural litters, lightweight formulas are more easily tracked than heavier clay litters, more expensive on average than clay litters

FAQs about cat toileting

How many times a day does a cat normally use the litter box?

On average, cats urinate two to four times a day, but according to Sueda, this can vary from cat to cat. Cleaning litter boxes at least once daily can help guardians determine if there’s a change in frequency, which may indicate a health problem.

Typically, cats defecate one to two times a day, but this, too, can vary from cat to cat. Like with urination, sudden changes in frequency may indicate a health problem.

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What size and how many litter boxes do I need?

A litter box should be at least 1.5 times the length of a cat, large enough for them to comfortably scratch and bury their waste. The standard rule of thumb is to have one litter box per cat plus one extra, and ideally one on each floor of a home. A home with multiple cats, however, may be able to get away with fewer extra-large litter boxes as long as they are cleaned at least twice a day, according to Sueda. See our guide to the best litter boxes for more on this.

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What does it mean if a cat stops urinating?

If a cat stops urinating altogether, it is likely they are experiencing a feline urinary tract disease (FLUTD) such as bladder inflammation or urinary stones or crystals. Male cats are particularly susceptible to the latter. “Male cats have a very narrow urethra, so crystals and mucus can form a plug or a single tiny stone may become lodged anywhere along this narrow tube,” said Tannert.

If a cat is unable to urinate, deadly toxins begin building up. Death can occur if the blockage isn’t removed by a veterinarian within 24 to 48 hours. If a veterinarian rules out medical problems like FLUTD, anxiety may be the culprit, a problem a veterinary behaviorist is best equipped to handle.

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What does it mean if a cat goes outside the litter box?

According to Calder, cats that eliminate outside the litter box are engaging in one of two behaviors: toileting or marking. In toileting (also called inappropriate elimination), a cat has found a place to do their business outside of the litter box. Sometimes, this behavior occurs when a cat does not like the location or size of their litter pan, the type of litter in the pan, or the cleanliness of the litter.

Other times, going outside the box is related to anxiety (for example, a cat who worries about being ambushed by another pet while using the litter box may stop using it altogether) or to a medical problem such as FLUTD. A cat may also choose to go outside of the litter box if they find a spot that satisfies their need to scratch and bury their waste, such as a pile of dirty laundry or a potted plant.

Whereas toileting typically occurs on horizontal surfaces, marking occurs on vertical surfaces. Instead of squatting, when a cat marks they back up with a raised tail to spray their pheromones. “Marking cats are trying to communicate something, and most have some kind of conflict or anxiety,” said Calder. Cats that mark are typically intact males, but fixed males and females can spray, too.

Our sources

Dr. Christine Calder, veterinary behaviorist at Midcoast Humane in Brunswick, Maine

Dr. Zay Satchu, chief veterinary officer, Bond Vet, New York, New York

Dr. Karen Sueda, veterinary behaviorist at VCA West Los Angeles Animal Hospital, Los Angeles, California

Dr. Catherine Tannert, veterinarian at VCA Old Marple in Springfield, Pennsylvania