The short answer for mice
Yes, with one important split by sex. A female mouse should never live alone: mice are group animals, and females rely on cage mates for warmth, grooming and confidence. A male mouse is the exception to the rule, because adult males defend territory and will usually fight a male cage mate seriously once they mature. So the practical answer is to adopt females in a pair or small group, and to house a male on his own, with plenty of human contact and things to do instead.
Why female mice need their group
Mice in the wild live in loose family groups, and that social wiring does not switch off in a pet tank. Female mice sleep pressed together in a shared nest, groom each other's hard-to-reach places, and take turns exploring while others rest, which softens the stress of being a small prey animal. A female kept alone has nobody to do any of that with. Owners often describe the result as a mouse who hides constantly, moves less, eats without enthusiasm and startles at small sounds — not an illness, just a social animal missing its society. Company for a female mouse is not an optional extra; it sits alongside bedding and water as a basic need.
Why male mice are wired differently
A male mouse treats shared space as territory to defend against rivals. Two males raised together sometimes get along while young, then fall out badly as they mature, and mouse fights escalate quickly — bites to the face, tail and underside are common and can need veterinary care. Because of that risk, experienced keepers house males singly from the start. A solo male is not a lonely one by default: his social needs shift toward his owner, and daily gentle handling, a wheel, deep bedding for burrowing and food scattered to forage for fill his time well. What he cannot have safely is another male inside his fence line.
Setting up a group that stays peaceful
If you adopt females, start with two or three from the same existing group where you can, because mice who already know each other skip the introduction tension entirely. Females from different sources can usually be introduced on neutral ground — a clean playpen, or a freshly cleaned tank carrying no established smells — with several hides so nobody gets cornered, and watched closely for the first day. Brief squabbles over food in the first hours are normal settling behaviour. Chasing that draws blood, or a mouse who cannot eat, drink or sleep in peace, is not normal, and means separate housing and a rethink. Give the group more floor space and more hides than you think they need, and scatter food instead of relying on one bowl, and the hierarchy mostly settles itself.
Signs the social setup needs changing
Watch a lone female for quiet signs: sleeping out in the open instead of in a nest, a dull coat from reduced grooming, slow weight loss, or a mouse who was curious becoming permanently hidden. In a group, watch for one mouse always eating last, sleeping apart from the others, or carrying small bite marks. Any of those means the social arrangement, not the individual mouse, needs adjusting first. With KinsLe's Care Teams working behind the scenes, the daily spot-clean, the water check and the weekly once-over of every mouse can each be assigned to whoever helps you, and finished tasks are marked with a timestamp — so a change in one mouse is noticed by the person doing that day's check, not lost between helpers.