How to set up a litter box your cat will use

Whether you’re getting ready for a new cat or your cat has started going somewhere else, the litter box is the place to start. Most litter box problems are solved by the setup: how many boxes you have, where they are, how big they are, what’s in them and how often they’re cleaned.

The goal is a box your cat would choose over any rug in the house: big, clean, easy to reach and quiet. Here’s what veterinary guidelines and research say cats prefer.

How many litter boxes do you need, and where?

The standard veterinary rule is one box per cat, plus one extra. Two cats need three boxes. Even a single cat often does better with two.

Where the boxes go matters just as much. Three boxes lined up in one room count as one big box to your cats, so spread them out:

• One box on every floor of your home, especially for kittens, seniors and cats with urinary issues.
• Quiet, low-traffic spots with two ways out. A cat cornered in a closet by another pet, a child or a dog may stop using that box.
• Away from food and water. Cats prefer to keep eating and toileting separate.
• Away from noisy or sudden things, such as washing machines, furnaces, dog beds and the front door.
• Easy to reach at all hours. Check that no door gets closed at night, there’s no baby gate in the way, and no dog is guarding the route.

Size: bigger than you think

Most commercial litter boxes are too small. A study of box size preference (Guy et al., 2014) found that cats preferred larger boxes.

A good rule is a box at least 1.5 times your cat’s length. Measure your cat from the nose to the base of the tail and multiply by 1.5. For many adult cats, that works out to roughly 24 to 28 inches (60 to 70 cm), which is longer than most standard boxes.

A large plastic under-bed storage bin makes a roomy, cheap litter box. Leave it open, with no lid. If the sides are high, cut a low entry on one side and sand or tape the edge smooth. Veterinary handouts on solving litter box problems recommend this.

Covered or open?

In a study of 27 cats offered both types (Grigg et al., 2013), most cats used covered and open boxes about equally. A few cats had a strong preference, and those preferences went both ways.

Veterinary guidance still generally favors open boxes. They let odor escape, they’re easier to keep clean, and they let a cat see anyone approaching, which matters in homes with more than one cat.

If your cat is having accidents and the box is covered, take the lid off, or put an open box next to it and let your cat vote. While you’re fixing a problem, avoid top-entry and self-cleaning boxes too. Some cats find the motors and moving parts frightening.

Which litter cats prefer

Most cats prefer unscented, fine-grained clumping litter, about 1 to 2 inches (3 to 5 cm) deep. Strong fragrances are for humans. A cat’s nose is far more sensitive than ours, and scented litter or deodorizers near the box can put cats off.

• Changing litter? Do it gradually. Mix increasing amounts of the new litter into the old over a week or two.
• Not sure what your cat likes? Run a litter cafeteria: put two or three boxes side by side with different litters for a week and see which gets used most. Then spread the boxes out again with the winner.
• Skip plastic liners. Many cats dislike how their claws catch in them.

How often to clean the litter box

Research on litter box appeal (Ellis et al., 2017) found that cats avoided boxes with waste left in them, and concluded that maintenance is the key factor in good box use. Waste left in the box is the most common, most fixable problem.

• Scoop at least once a day, ideally twice.
• Top up the litter after scooping to keep the depth steady.
• Wash each box every 1 to 2 weeks with mild, unscented soap and warm water. Rinse and dry it fully before refilling.
• Replace boxes that are scratched or still smell after washing. Scratched plastic holds odor.
• Avoid strong-smelling cleaners on or near the box, including ammonia, bleach (unless rinsed thoroughly), citrus and pine.

Setups for senior cats and kittens

Older cats and kittens need a few changes to the standard setup:

• Senior cats: use boxes with a very low entry, 2 to 3 inches, put a box on every floor and near favorite resting spots, and add a night light. Arthritis is common in older cats and often missed, so ask your vet about pain relief.
• Kittens: they have small bladders and little warning. Give them several low boxes close to where they play and sleep, and keep them in a smaller area at first.

When the setup isn’t the whole answer

A few habits can undo a good setup. Don’t move the only box to a better place suddenly: add the new box first, then remove the old one later. Don’t switch litter brands overnight or buy scented litter to control odor, and don’t put all the boxes side by side in one room.

If there’s no clear improvement after three weeks with a good setup, ask your vet about a referral to a veterinary behaviorist or a certified cat behavior consultant.