A one-bedroom flat leaves no neutral territory and no room to spare, so a staged introduction here works by dividing the home twice over: in place, with each cat holding part of the flat, and in time, with each cat taking turns in the other's part while it stands empty. Done patiently, the small footprint can even help, because every swap teaches both cats that the whole flat carries both scents and that the other cat is a normal feature of the home rather than an intruder at the door.
Set Up Two Bases and Begin the Site Swaps
Give the incoming cat the bedroom as a complete base before arrival: a litter tray, food and water set apart from each other, a scratching surface, and a hiding place where the cat can be left entirely alone. The resident cat holds the living area, with its own full set of resources, so neither cat's daily life depends on entering the other's territory. After the incoming cat has eaten, used the tray and begun to explore the bedroom confidently, start site swaps: move the resident cat into the bedroom while the incoming cat explores the living area, with neither cat seeing the other during the exchange. Swap daily if both stay relaxed. Each cat investigates fresh scent at its own pace, rubs against furniture in the other's space, and returns to a base that now smells a little more shared.
Door Feeding and Bedding Swaps Build the Association
Feed both cats at the same time, one on each side of the closed bedroom door, starting far enough back that each eats without staring at the door, then moving the bowls gradually closer across days as long as eating stays relaxed. The lesson you are building is plain: good things happen when the other cat is near. Alongside feeding, swap bedding between the two bases so each cat sleeps on a blanket carrying the other's scent, and swap a rubbed cheek cloth if both cats tolerate scent cloths. Watch the signals honestly: eating well, playing and resting in the open mean the pace is right, while hissing at the door, refusing food or hiding for long stretches mean you hold the current stage longer or step back one stage. In a small flat there is no prize for speed, and a stage repeated costs days, while a stage rushed can cost weeks.
Barrier Contact, Then Short Shared Time
Expect the timeline to be measured in weeks, and protect one rule throughout: the resident cat's original base and routines are never the price of progress. If a shared session goes badly, separate calmly, return both cats to their bases with food, and repeat the previous stage for a few more days rather than pressing on. Setbacks handled quietly are part of a staged introduction, not evidence that the cats cannot live together, and in a one-bedroom flat the staged route is the only kind available to you.
When both cats eat calmly close to the door and show curiosity rather than fixed staring, let them see each other through a barrier such as a tall pet gate or a door opened a crack and secured, keeping sessions short and feeding or playing on both sides so the sight of the other cat predicts good things. Hissing through a barrier at the start is information, not failure; end the session, feed separately and try again another day. Prepare for shared time by duplicating everything first: at least two litter trays in different spots, separate feeding stations, water in more than one place, and high and low resting spots for both. The first shared sessions should be brief, supervised and in the larger room, with an easy exit route for each cat. Build the whole plan into KinsLe, where Care Teams tracks swap turns, feeding stages and barrier sessions for both partners, so the protocol survives busy days.