How should I introduce a new cat or kitten to my existing cat?

How well cats get along with each other is influenced by a range of factors related to the owner, the cats, the environment, and husbandry. In some situations, cats may learn to get along. In other cases, they may not be compatible. Patience is absolutely key; each cat is an individual and some may get on quickly, while others may take a long time to get used to sharing their home with another cat.

Planning and preparation

The success of an introduction depends largely on careful planning and preparation.

• Socialisation – Preparation begins long before you bring a new cat home, with socialisation of your existing cat. Socialisation involves exposing animals to a range of experiences to help them prepare for and cope with different situations, interactions, and environments.
• Matching – When selecting your new cat, think about how well matched they will be for your existing cat.
• Health check – Make sure your cats have had recent health checks, and are up to date with their vaccinations, worming, and external parasite control, so they are in the best shape to cope with the introduction process and will not pose health risks to one another.
• Preparing the environment – make sure that there will be enough resources for all of the cats in your household. Each cat needs multiple and separated resources immediately available to them at all times (e.g., food, water, toileting areas, scratching areas, play areas, and resting or sleeping areas). See the RSPCA Guide to Keeping Your Cat Safe at and Happy at Home for more information.
• Cat containment – Keeping a cat contained on your property is especially important for new cats who are unfamiliar with the area.
• Pheromone diffusers – Activating pheromone diffusers for a few days before bringing your new cat home, may help calm your existing cat and the new arrival.
• A transition space – Prepare a transition space where you can keep your new cat away from your existing cat(s). Make sure the space has everything they need (e.g., a comfortable bed, toys, scratching post, litter trays, food, water).

Bringing your new cat home

First, make sure your new cat is comfortable in their transition space. For more information see the Knowledgebase article ‘How do I help my cat adjust to a new home?’.

Gradual introduction

To maximise the chance that unfamiliar cats will get along, introduce them gradually, step by step. Observe your cats’ behaviour to see if you should proceed to the next step. Be prepared for the introduction process to take weeks to months.

Step 1: Scent swapping

Rub a towel over your existing cat and leave the towel in your new cat’s transition space. Rub a different towel over your new cat and leave that towel in your existing cat’s area. Repeat daily until your cats are comfortable with each other’s scent/a communal scent.

Step 2: Allow independent exploration

Allow them to explore each other’s areas of the home without the other present.

Step 3: Supervised visual contact

Allow short sessions of supervised visual contact behind a barrier (e.g., child gate or screen). If they are comfortable, gradually increase the duration of visual contact.

Use treats and play with each cat separately and physically separated but in the communal space together. This helps them to associate positive experiences with the presence of the other cat. Make sure that each cat can retreat of they want to and never force any interactions.

Step 4: Supervised free contact

If your cats seem comfortable going about their own activities behind a barrier, begin short, supervised sessions where the barrier is removed. Maintain separate resources, ensure they have their own areas to retreat to, and feed them separately. As above, use treats and play with each cat separately and physically separated but in the communal space together. If they seem to get along, gradually increase supervised free contact sessions.

Step 5: Unsupervised free contact

Once your cats are comfortable with supervised free contact, gradually increase the amount of time they spend together unsupervised, and slowly phase out supervision.

Managing cat conflict

If persistent conflict occurs, seek advice from a vet or veterinary behaviourist. Separation, behaviour modification and, potentially, medications may be required at least in the short-term.

When you have more than one cat in your family, social acceptance between the cats is not guaranteed. When adding a new cat to a family with an existing cat or cats, the new cat must be viewed and treated as a separate social entity/group from the existing cats, at least initially, although that may change if the existing cats accept the new cat into their social group. For more information on multi-cat households and cat social groups see the RSPCA Guide to Keeping Your Cat Safe at and Happy at Home.

Good husbandry

To maximise the chance that cats will thrive together in the same household, it is necessary to provide them with an environment that is optimised to meet the cats’ physical and mental needs, allows and encourages the expression of normal feline behaviours, minimises stress, and promotes good health and welfare. Providing each cat with multiple and separated resources (e.g., food, water, toileting areas, scratching areas, play areas and toys, and resting or sleeping areas) is critical. For more information on how to keep all the cats in your household happy and healthy, see the RSPCA Guide to Keeping Your Cat Safe at and Happy at Home.