Introduce a new cat by keeping her completely separate at first, letting the cats learn each other through scent and sound, and only allowing face-to-face meetings after both are eating and relaxing calmly near a closed door. Most successful introductions take days to a few weeks, and moving slowly is what prevents the hissing, chasing, and litter box setbacks that come from a same-day meeting in the living room.
Start With a Sanctuary Room
Set up one quiet room for the newcomer before she arrives: litter box away from food, water, scratcher, hiding spot, and a cozy bed. Your resident cat keeps the rest of the home and her normal routine. This separation is not rejection — it gives the new cat a safe base to decompress after travel and shelter life, and it gives your resident cat time to notice a change without feeling invaded.
Visit the new cat for calm play and company, wash your hands between cats at first, and let your resident cat sniff under the door without correction. A little curiosity at the door is a good sign. Constant yowling, lunging at the door, or refusing food on either side means you need more time at this stage.
Swap Scent Before Sight
Scent is how cats build familiarity. Swap bedding daily so each cat sleeps on something that smells like the other. Rub a soft cloth gently on one cat's cheeks, then leave it near the other cat's food bowl or resting spot. You can also swap rooms briefly: let the newcomer explore the home while your resident cat spends time in the sanctuary room sniffing at her own pace, with no chance of an ambush meeting in the hallway.
Next, feed meals or high-value treats on opposite sides of the closed door. Start far enough back that both cats eat relaxed, then gradually move bowls closer over several sessions. If one cat stops eating, you moved too fast — increase distance and try again tomorrow.
First Visual Meetings Should Be Short and Controlled
When door feeding is calm, crack the door with a baby gate or screen so the cats can see each other but not touch. Keep sessions brief — a few minutes of parallel treats or play at a distance — and end before tension rises. Watch ears, tails, and posture, not just noise. A quiet stare can be more concerning than a single hiss followed by looking away.
Only after several calm visual sessions should you allow time in the same room, supervised, with escape routes for both cats and no picking up or forcing greetings. Let them choose distance. Short, boring meetings are a win.
Troubleshooting and When to Slow Down
If you see persistent staring, stalking, blocking, or one cat hiding and not eating, return to the previous step for a few days. Do not punish warnings, and do not leave new cats unsupervised together until you have had many relaxed shared sessions. Kittens sometimes integrate faster, while adult cats with unknown histories, former outdoor cats, or cats who have lived solo for years often need the longer timeline — that is normal, not failure.
Seek veterinary advice if either cat stops eating for more than a day, shows litter box changes, or seems unwell, since stress and illness can overlap during a transition.
Keeping the Introduction Coordinated at Home
Introductions fall apart when one person opens the door early, another feeds in the wrong place, and no one remembers which step you reached. Agree between you who is handling sanctuary-room visits, feeding and play at each step, so nobody opens the door early or lets the newcomer roam free too soon. That consistency is reassuring for both cats. Ready to plan your next new-pet transition more smoothly? KinsLe Family Sharing also lets a relative you have picked view both cats' profiles.