How to Introduce a New Cat to Your Resident Cat
In this guide
Cats are territorial, and a newcomer can feel like an invasion. Putting two unfamiliar cats together and "letting them sort it out" often leads to hissing, fighting, and long-term stress.
A gradual introduction over one to several weeks takes patience, but it greatly improves the chances of a peaceful — or even friendly — relationship.
Step 1: A separate base camp
Set up a room for the new cat with food, water, a litter box, a bed, a scratching post, and hiding places. Keep the door closed. This lets the new cat settle and the resident cat keep the rest of the house.
Step 2: Scent swapping
Cats recognise each other by smell first. Swap bedding between the cats, and gently rub a soft cloth on each cat's cheeks and leave it near the other cat's food. Reward calm reactions with treats.
After a few days, let the cats swap spaces while the other is shut away, so each can explore the other's scent.
Step 3: Seeing without touching
Use a baby gate, a screen door, or a door opened a crack to let the cats see each other briefly during meals or play. Keep sessions short and positive, and increase their length gradually.
Step 4: Supervised time together
When both cats are relaxed during sightings, allow short supervised sessions in the same room. Use play and treats to keep things positive, and separate them calmly before tension builds.
- Warning signs: flattened ears, puffed tail, staring, growling, or swatting
- Good signs: relaxed body language, sniffing, slow blinks, ignoring each other
Resources reduce conflict
Provide plenty of resources in different places: food bowls, water bowls, litter boxes (one per cat plus one), beds, and high perches. Competition for resources is a major cause of tension between cats.
If things go wrong
If fighting breaks out, do not use your hands to separate cats. Make a noise or put a cushion between them, then separate them and go back a step. If problems continue, ask your vet or a qualified feline behaviourist for help.
This is general pet-care information, not veterinary advice. Every animal is different — if you are worried about your pet's health or behaviour, contact your veterinarian. In an emergency or a suspected poisoning, call your vet or an animal poison-control line immediately.