How many litter boxes you actually need, how much litter to buy, how to introduce a new cat, and how to keep the peace — the whole multi-cat picture in one place.
Quick answer
The golden rule is one litter box per cat, plus one extra, spread around the home so no cat can guard them — and the same one-per-cat-plus-one logic applies to food and water stations. Introduce any new cat slowly with scent-swapping and staged meetings, provide plentiful, well-spaced resources, and watch each cat's litter and water habits, since changes are often the first sign of a health issue.
More cats can mean more joy — or more friction — and the difference usually comes down to resources and introductions. Cats are territorial, and most multi-cat conflict traces back to too few, or badly placed, resources.
This guide covers the practical math of litter boxes and litter, how to add a second cat without lasting tension, and how to keep a shared home harmonious. It also touches on health monitoring, because in a multi-cat home the litter box and water bowl are surprisingly good early-warning systems.
Litter boxes & litter
How many boxes, how much litter, and how deep.
A harmonious multi-cat home
Adding a cat and keeping the peace between them.
Water in a multi-cat home
The tricky question of which cat is drinking how much.
Related guides
Frequently asked questions
How many litter boxes do I need for multiple cats?
Follow the one-per-cat-plus-one rule: two cats need three boxes, three cats need four, spread around the home rather than clustered so no cat can guard them. The same logic — plentiful, well-spaced resources — applies to food and water stations.
How do I introduce a second cat?
Slowly. Start with the cats in separate spaces, swap their scents, then move to brief, controlled meetings, letting them set the pace. A rushed, face-to-face introduction often causes lasting tension — a patient, staged one is the biggest predictor of a peaceful home.
How much litter should each box have?
Around two to three inches of depth — enough for a cat to dig and cover, and for clumping litter to form solid clumps, but not so deep it spills. Each box needs its own litter to that depth, so a multi-cat home goes through considerably more.
Should I get a second cat?
It depends on your current cat's temperament and whether you can afford and house two comfortably. Younger, sociable cats often thrive with a companion; older, territorial, or contentedly solo cats may not. Provide a resource of each type per cat plus one spare, and introduce them slowly.
Sources & further reading
MyNubs content is researched from published guidance by veterinary and other authoritative organizations. For this topic, see:
This article is for general educational purposes and reflects guidance from veterinary and other authoritative sources. It isn’t a substitute for professional veterinary advice — every animal is different, so please consult your veterinarian about your pet’s individual needs.