Good with other pets means safely apart
A Campbell's dwarf hamster is fine in a multi-pet home only when good with other pets means never meeting them. This dwarf weighs very little, moves in quick darts that trigger chase instincts, and has no defence against even a playful dog or a curious cat. A cat staring through the bars for hours, a dog nudging the enclosure with its nose, or a ferret anywhere near the cage all create chronic fear in a prey animal that cannot leave. The hamster does not need to be attacked to be harmed, so the goal is a setup where it never features in the other animals' daily entertainment.
Dogs, cats and the secure-room rule
Dogs and cats decide how the Campbell's dwarf hamster's housing must be arranged. Place the enclosure in a room that can be closed, ideally raised on a stable stand a dog cannot nose against and a cat cannot leap onto, with a lid or mesh top fastened so a determined paw cannot lift it. Never carry the hamster through a room where a dog is loose, and never allow floor or ball-style exercise anywhere another pet might enter, because one door opened at the wrong moment is enough. Teach dogs a solid leave response around the closed hamster room door, and redirect cats with their own play rather than letting them treat the cage as viewing. If the only available space is a room cats freely patrol at night, reconsider the placement or the purchase, because night is exactly when this nocturnal hamster is out and most visible.
Other hamsters and small mammals
Other small pets raise a different set of questions for a Campbell's dwarf hamster. Campbell's are one of the dwarf species sometimes kept in same-sex pairs from a young age, yet pairings can break down, and a fight between dwarfs can injure quickly, so any pair needs space, duplicate wheels, food spots and hides, plus a spare enclosure ready if separation becomes necessary. Never house a Campbell's with a different hamster species, and never introduce an adult stranger expecting friendship. Rabbits, guinea pigs and rats should live entirely separately too. They are not companions for a dwarf hamster, their size and behaviour can injure or terrify it, and shared floor time benefits none of them, however calm the larger animal seems while being watched by its owner.
Escapes are the real multi-pet emergency
Escape prevention matters more in a multi-pet home than any introduction plan for a Campbell's dwarf hamster. Check lid fastenings, door catches, bar spacing and any chewed corner each time you clean or add a chew, because a dwarf that slips out faces being hunted, trapped behind furniture or injured before anyone notices the empty cage. Keep a humane live trap or a familiar hide-and-food station plan in mind, search quietly at dusk when the hamster wakes, and shut other pets out of the search area completely. Tell everyone in the house the rule that an escaped hamster means pets are closed away first and searching second. A hamster recovered after a cat encounter needs prompt veterinary advice even if it looks unhurt, because small punctures hide under fur and infection follows quickly.
Deciding honestly whether your home fits
A home with other pets suits a Campbell's dwarf hamster if it can offer one reliably closed, calm room, a secure enclosure and a family that treats separation as permanent rather than a phase before introductions. It is a poor fit if cats roam every room freely, a high-prey-drive dog fixates on small animals and cannot be kept from the cage area, or children plan to show the hamster to the dog as part of the fun. None of that reflects badly on the other pets. It simply respects what a tiny prey animal experiences. Recording the room rule, lid checks and escape plan where all helpers see them helps, and KinsLe Family Sharing puts those Campbell's safety details in front of every household member who might feed, clean or visit.