A litter tray looks like the simplest piece of cat equipment, but the details of how it is set up affect whether a cat uses it. This article draws on guidance from International Cat Care, an international feline welfare charity, and covers general husbandry rather than any nation’s law.
How big should the tray be?
International Cat Care’s advice is that the ideal tray length is one and a half times the length of your cat from the nose to the base of the tail. Rectangular trays are recommended over corner, triangular or oval designs. The charity notes that many standard-sized trays are too small.
Two adjustments are worth knowing. Kittens outgrow their first tray, so the size needs upgrading as they grow. For cats with reduced mobility, such as arthritic cats, the charity suggests lower-sided trays that are easier to step into.
Open or hooded?
International Cat Care says open trays are preferable. Covered designs can make cats feel vulnerable because there are fewer ways out, large cats can struggle to position themselves in a smaller hooded unit, and the odour trapped inside can make the litter seem dirtier to a cat than it does to you, which may reduce use. If you do use a covered tray, the charity says it should have any flap removed and be oversized for your pet.
How many trays?
The charity recommends one tray per cat plus at least one additional tray, spread through the house. In a multi-cat home this matters because a cat blocked from a single tray by another cat may look for somewhere else. In its guidance on soiling indoors, the charity likewise recommends one tray per cat and a spare.
Litter type and depth
- Depth: approximately 3 cm of litter.
- Texture: fine, sand-like litter is preferred, and clumping litter is easier to remove once soiled.
- Avoid: scented litters, polythene liners and deodorants, which the charity says cats find overpowering.
Where to put the tray
Position trays in quiet areas away from food and water, and away from windows and cat flaps where outside threats can seem close. For several cats, distribute trays through the home so that one cat cannot guard access to all of them. Placing feeding bowls elsewhere rather than beside the tray keeps the two activities apart.
Cleaning routine
International Cat Care’s guidance on choosing a tray recommends scooping at least twice daily. For a complete wash-out it suggests every two to four weeks for clumping litter and weekly for non-clumping litter, while its guidance on soiling indoors mentions complete weekly changes. If you are unsure, the weekly reading is the more cautious one. Use hot water and biological detergent, rinse and dry thoroughly before refilling, and avoid disinfectants that are toxic to cats. The charity names Dettol as an example, and its soiling guidance warns against ammonia-based cleaners and phenol-containing disinfectants.
If a cat has soiled elsewhere in the house, the charity recommends an enzymatic cleaner designed for cat waste, or a 10 per cent biological washing powder solution followed by surgical spirit. The aim, in its words, is to remove any smell your cat can detect, so that the spot does not become a repeat toileting site.
A quick set-up checklist
- Measure your cat from nose to tail base and multiply by one and a half to find the minimum tray length.
- Count your cats and add one to get the number of trays.
- Fill to about 3 cm with fine, unscented litter, preferably a clumping type.
- Place trays in quiet spots, away from bowls, windows and cat flaps.
- Scoop at least twice a day and wash out on a fixed schedule with hot water and biological detergent.
- Skip liners, deodorants and scented products, and keep toxic disinfectants well away from the tray.
Cats have strong preferences about their toilets, and the charity’s list of behavioural causes for indoor soiling reads like a list of ways the set-up can fall short. Working through the checklist is therefore a sensible first step whenever a cat starts to avoid its tray, before you assume the problem lies with the cat.
When soiling is not a set-up problem
Toileting outside the tray has both behavioural and medical causes. On the behavioural side, International Cat Care lists dirty or too few trays, the wrong or scented litter, exposed or busy positions, bad associations with the tray, fear or anxiety while toileting, and the loss of preferred outdoor sites. Medical causes it lists include urinary tract disease, diarrhoea, stress-related cystitis, hyperthyroidism, diabetes and pain, such as arthritis in senior cats.
Because the list of medical causes is long, a sudden change in toileting habits is worth raising with your vet rather than assuming it is a behaviour problem. The charity is specific about one emergency: contact a vet immediately if your cat cannot pass urine or produces only small amounts, since that can indicate a urinary obstruction.
The bottom line
According to International Cat Care, a good litter set-up means a rectangular, open tray about one and a half times your cat’s length, one tray per cat plus a spare, roughly 3 cm of fine unscented litter, quiet positions away from food, scooping at least twice a day and regular full washes with cat-safe cleaning products. If a cat starts toileting elsewhere, check the set-up first, involve your vet because medical causes are common, and seek help straight away if your cat cannot pass urine.