I. The Basics of Cat Litter Boxes
Many people take it for granted that cats will use a litter box, so they give little thought to choosing the right litter box, cat litter, or placement location. When a cat avoids the litter box, owners are often shocked, annoyed, or confused. However, most litter box issues can be avoided by understanding a cat’s elimination behavior and putting in a little extra effort.
First, it’s important to note that a cat’s use of a litter box isn’t some magical instinct. Their wild ancestors would bury feces and urine with soft materials like soil and sand after eliminating in their territory. While the biological reason for this burying behavior isn’t fully understood, it’s known to reduce disease transmission and hide the cat’s presence from prey and predators.
This means that to keep a cat indoors, you must provide a litter box filled with a soft substrate (cat litter) for elimination. Fortunately, most cats readily adapt to the litter we provide as a substitute for natural soil or sand.
II. Cat Elimination Behavior
Scientific knowledge about cat elimination behavior is relatively limited, but researchers are beginning to study this topic, and their findings help resolve or prevent litter box problems.
We now know that kittens are born with an instinct to eliminate on soft surfaces. This behavior typically emerges when kittens are 3–4 weeks old, around the time they gain voluntary control over their bladder and bowels. They do not need to learn this behavior from their mother or other cats—even hand-reared kittens who have never interacted with other cats will perform these standard elimination actions.
Before eliminating, a cat will first sniff the area, then scratch the surface with its front paws as if digging a hole. Next, the cat turns around, squats, and urinates or defecates on the scratched spot. Afterward, it turns back to sniff the soiled area and scratches the surface again, as if burying the waste. Some cats repeat the sniffing and scratching actions multiple times before leaving.
There is significant individual variation in a cat’s scratching behavior. Some only wave their paws a couple of times symbolically without actually burying the waste, while others dig vigorously as if building a sandcastle. These differences are normal unless the cat abandons the area hastily due to illness or aversion to the surface or location.
III. Factors Affecting Elimination Behavior
A cat’s choice of elimination spot depends on several key factors, with surface texture being the most important. A recent study found that cats prefer fine-grained sandy surfaces (such as commercial clumping litter) over coarser materials. The study also noted that cats dislike dusty or strongly scented litters.
The type of litter box may also play a crucial role, and animal behavior experts offer the following recommendations:
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The litter box must be large enough to accommodate the cat’s elimination movements
Cats perform a series of actions before eliminating, including sniffing, selecting a spot, turning around, and scratching. Larger cats need bigger litter boxes to complete these movements comfortably—using the litter box should be a stress-free experience, and a cramped space can make a cat anxious. Some cats prefer enclosed litter boxes (with a lid) for privacy, while others favor open-top boxes for better visibility. Some litter boxes have high sides to prevent litter scatter, which some cats like and others dislike.
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Odor is another critical factor
A faint urine smell can attract cats to use the same spot repeatedly, but a strong, stale odor (from a rarely cleaned litter box) will repel them.
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Litter box placement is also essential
The box should be placed away from the cat’s food, water, sleeping, and play areas. It should be easily accessible yet slightly private, avoiding high-traffic human pathways. However, it should not be hidden in dark corners of basements or attics. Cats usually avoid dark, cold, or overly hot areas, as well as spots near noisy appliances like air conditioners, washing machines, or dryers. Additionally, cats prefer open spaces where they can escape easily if threatened by a dog or another cat.
IV. Preventing Litter Box Problems
Key Points to Remember:
If you bring a new cat home, try to use the same brand of litter and type of litter box it was used to previously. Most cats dislike change—never switch litters just because a brand is on sale. Stick to one brand unless you or your cat have a specific issue or complaint.
Keep the litter box in a fixed location; do not move it arbitrarily. If you don’t know the litter brand your new cat used, start with a fine-grained, unscented litter. Avoid placing deodorizers or air fresheners near the litter box.
Follow the one litter box per cat plus one extra rule. Ensure the largest cat in your household has enough space to use the box comfortably, so there’s always an available litter box for every cat. If adding a rim or lid makes the box too cramped, skip these accessories.
Place litter boxes in accessible, private, warm, and well-lit areas, away from food, water, and beds. For multi-story homes, put a litter box on each floor—this reduces the likelihood of elimination problems. Choose quiet, open spots where cats don’t have to worry about noise or sudden attacks while using the box.
Clean the litter box at least once a day. For non-clumping litter, replace all the litter and wash the box with detergent every 3–4 days; clean it more frequently if the box is used heavily. For clumping litter, scoop out waste clumps each time and add fresh litter as needed. Even with careful maintenance, litter will develop an odor over time—replace all the litter and wash the box every 3–4 weeks.
Kittens and new cats do not need to be trained to use a litter box. Some people mistakenly place cats in the box and force their paws to dig in the litter, which can make the cat fear the box and avoid it. Simply show the cat where the litter box is located and follow the above guidelines.
Observe your cat’s litter box habits regularly to check for normal behavior. Watch for signs of difficulty or pain while eliminating, a litter box that’s too small, trouble accessing the box, or signs of aversion to the box or litter (e.g., no scratching before elimination, fleeing immediately after, or standing with front paws on the box edge instead of stepping inside).
V. Solving Litter Box Avoidance Issues
If your cat is not using the litter box, what should you do?
Elimination problems can stem from many causes, including illness or medication side effects—urinary tract infections and gastrointestinal issues are the most common medical culprits. Cats with medication-related issues may show no obvious signs of illness, so without proper treatment, environmental adjustments alone are unlikely to resolve the problem. Always consult a veterinarian first for a physical exam and tests to rule out medical causes before addressing behavioral issues.
Additionally, cats may exhibit spraying behavior, which is unrelated to elimination. Spraying is a territorial marking behavior, not a need to empty the bladder. It often worsens during mating season or when the cat is stressed or scared. A spraying cat will stand upright, hold its tail high, and spray small amounts of urine on vertical surfaces like walls or furniture. This behavior should be distinguished from abnormal elimination outside the litter box.
If your veterinarian confirms that the issue is behavioral, animal behavior experts recommend addressing the following potential causes, which relate to preferences for location, surface texture, litter/litter box type, or fear-related factors. No scientific research supports the idea that cats eliminate outside the litter box to “get revenge” or annoy their owners.
1. Preference for Location
If a cat eliminates outside the litter box but shows no preference for the surface (e.g., uses random spots), it will usually stick to one or two areas. These spots may be where a litter box was previously placed, or areas that are easily accessible, private, and offer an escape route.
Solutions:
Block access to the preferred off-limits spots—this may encourage the cat to return to the litter box.
Move the litter box to the cat’s preferred spot. If the cat starts using the box there, the problem was simply a location preference.
If the preferred spot is not suitable for a permanent litter box, gradually move the box a few inches each day to your desired location. Patience and compromise between you and your cat are key.
2. Preference for Surface Texture
Cats that avoid the litter box often target surfaces with a specific texture—most prefer soft surfaces like carpets, laundry, or beds, while others favor smooth surfaces like bathtubs, sinks, or tile floors.
Solutions:
3. Aversion to the Litter or Litter Box
Cats that dislike their litter box or litter may still use the box but avoid stepping inside fully (e.g., stand with front paws on the edge), skip burying waste, or shake their paws excessively after leaving. In severe cases, they may eliminate right next to the box. Even moving the box to their chosen spot or confining them with the box won’t resolve the issue.
Solutions:
For litter aversions, follow the surface texture preference tips above.
For other issues, address the root cause, which may include:
Litter that is too deep or too shallow.
A dirty litter box.
Lack of an escape route while using the box.
Insufficient privacy.
Loud noises or sudden sounds near the box.
A stressful path to the box (e.g., passing a hostile pet).
A negative experience in the box (e.g., pain while eliminating, being startled by a loud noise).
4. Fear-Related Issues
In these cases, the cat avoids the litter box not because of the box itself, but because it fears getting to the box or being in the box.
Common fear triggers:
Stress from moving to a new home, leading the cat to eliminate in more hidden spots than the litter box.
Punishment from owners (e.g., being dragged to the accident spot or forced into the litter box after an elimination incident).
Intimidation from other cats in the household, causing the cat to hide.
Solutions:
Litter box problems vary in complexity: Simple issues are easy to resolve on your own with quick adjustments, while complex problems may require more time, effort, or financial investment. Early detection and intervention are key to success—problems that persist for a long time become much harder to fix. For this reason, observe your cat’s elimination behavior regularly and contact your veterinarian immediately if you notice any abnormalities.
