The general rule of thumb is one litter box per cat, plus one extra โ so a two-cat household ideally has three boxes. Place boxes in quiet, low-traffic spots that are still easy to reach, and avoid clustering them all in one room if you can, since some cats prefer options.
Scoop at least once a day; cats are famously particular about a clean bathroom, and a dirty box is one of the most common reasons cats start going elsewhere. Do a full litter change and box scrub every one to two weeks depending on the litter type.
Unscented, fine-grained clumping litter is generally the most widely tolerated by cats, though every cat has preferences. If you notice sudden changes in litter box habits โ going outside the box, straining, or unusual frequency โ it's worth a vet visit, since it can signal a urinary issue.