How many litter boxes do I need?
How many litter boxes per cat? One per cat, plus one: that's the advice of both the American Association of Feline Practitioners and the ASPCA. Enter your cat's length and how many cats you have to get the number of boxes and the smallest size to buy.
How many litter boxes per cat
| Cats | Litter boxes | Places, at least |
|---|---|---|
| 1 cat | 2 | 2 |
| 2 cats | 3 | 2 |
| 3 cats | 4 | 2, more if you can |
| 4 cats | 5 | 2, more if you can |
| 5 cats | 6 | 2, more if you can |
One box per cat, plus one (AAFP, ASPCA). The AAFP's guidelines ask for at least 2 different locations, and more in a multi-cat home.
Why the extra box? A spare means there's always a clean one, and cats that don't get along can each have their own. The AAFP explains that in multi-cat homes, one cat may control access to the boxes, and that well-placed, easy-to-reach boxes help prevent cats from going elsewhere.
Litter box size: 1.5 times your cat
The AAFP's guidelines say cats spend more time in litter boxes that are at least 1.5 times the length of their body, measured from the nose to the base of the tail. Many commercial boxes are too small for larger cats.
| Cat's body length | Box length, at least |
|---|---|
| 14″ 36 cm | 21″ 53 cm |
| 16″ 41 cm | 24″ 61 cm |
| 18″ 46 cm | 27″ 69 cm |
| 20″ 51 cm | 30″ 76 cm |
| 22″ 56 cm | 33″ 84 cm |
Body length × 1.5 (AAFP). Measure the inside of the box, not the outside.
If you can't find a box that long, the AAFP suggests a sweater storage box, a cement mixing tub or a small dog litter pan instead.
Where to put the litter boxes
- In at least two places. The AAFP asks for two different locations at least, and more in a multi-cat home.
- Private, but easy to reach. The AAFP advises private spots that aren't next to noisy appliances.
- With a way out. Boxes should have at least two ways for a cat to come and go, so one cat can't trap another inside, the AAFP says.
- Within reach at all times. The ASPCA lists a box the cat can't easily get to among the common reasons cats go elsewhere.
Litter and cleaning
Most cats prefer a fine-grained, unscented litter, such as clumping litter, according to the AAFP. Many like it about 1.5 inches deep; the ASPCA says one to two inches, and that litter that's too deep can put a cat off. Some cats also dislike hoods and liners.
For cleaning, the AAFP's routine is: scoop once or twice a day; change clumping litter completely at least once a week, and clay litter at least every other day, more often when several cats share; then wash the box with warm, soapy water and dry it before refilling.
Kittens and older cats
Kittens need boxes with low sides they can climb into, the AAFP says, and a larger box as they grow. Older cats may need more boxes, bigger ones and more frequent cleaning, with low sides that are easy to step into and a night light for cats whose eyesight is failing. The ASPCA notes that boxes with high sides or top entries are hard for older cats and cats with physical limits to use. For crates and other gear, see the pet gear size calculators.
Questions owners ask
How many litter boxes do I need for 2 cats?
Three: one for each cat, plus one. The AAFP adds that they should be in at least two different places, so one cat can't guard them all.
Can two cats share one litter box?
Some will, but the AAFP and the ASPCA both advise one box per cat plus one. Too few boxes is one of the litter-box problems the ASPCA lists as a cause of cats going outside the box, and in multi-cat homes one cat may block another's access.
How big should a litter box be?
At least 1.5 times your cat's body length, from nose to the base of the tail, the AAFP says. Cats spend more time in boxes that size. For an 18-inch cat that's a box at least 27 inches long, larger than many boxes sold in stores.
How often should I clean the litter box?
The AAFP advises scooping once or twice a day, changing clumping litter completely at least once a week, and clay litter at least every other day, more often with several cats. Wash the box with warm, soapy water before refilling.
Why is my cat peeing outside the litter box?
The ASPCA lists dirty boxes, too few or too small boxes, hard-to-reach spots, hoods or liners, litter that's too deep, stress and conflict between cats. But the AAFP notes it often signals a medical problem, so see your vet first.