How To Introduce a Kitten to a Cat

Bringing home a kitten is a busy and exciting time—you need to schedule vet appointments and vaccinations, make sure you have all the gear your kitten needs, and help your new family member adjust to the home.  

Adding a kitten to your home when you already have a resident adult cat brings a few more considerations. But with the right tools and some patience, you can ensure the new kitten and adult cat will peacefully coexist. Here’s how to introduce a kitten to a cat.  

Why Are Introductions Important?

Taking the time to properly introduce your kitten to your cat is important for several reasons—one of the biggest is to prevent stress. Changes in environment and routine can have a profound impact on a cat’s physical and mental well-being. 

Cats under stress can develop: 

• Urinary tract disease 

• Viral respiratory infections 

• Decreased eating or drinking 

• Vomiting 

• Diarrhea 

From a behavioral standpoint, anxious cats can become destructive, aggressive, and avoidant. When you allow your cat and your kitten time to adjust to each other, you can prevent a lot of these negative behaviors.  

Another consideration is that an adult cat could be easily overwhelmed by a new, energetic family member and end up attacking the kitten. Fighting between the cats could reduce the chances that they will end up getting along in the future, because early negative interactions set the tone for their relationship and require more work to reverse.  

In addition, slowly socializing your kitten with your adult cat sets them up to grow into a confident and well-adjusted adult with improved tolerance to new things. Improper introductions can cause the kitten to become fearful or aggressive toward the adult cat and potentially develop generalized fear. 

How To Introduce a Kitten to a Cat

When introducing a kitten to an older cat, monitor them both for signs of agitation. Both cats should eat, drink, and use the litter box consistently during the introduction process.   

If you notice your cats are stressed, go back to the most recent successful step to give them more time adjusting before continuing.  

1. Set Up the Kitten’s Room

Dedicate private space for the kitten for the first few weeks they’re home with you. This space should have all the essentials, including: 

• Food and water bowls

• Comfortable beds for your kitten to rest in

• A cat tree for your new kitten to climb, scratch, and survey their new home

• Toys to keep your kitten occupied

• A litter box where they can learn to do their business

• Windows with perches so the kitten can look outdoors

• A door to separate the kitten from your adult cat 

Now is also a good time to start using calming products, such as Feliway MultiCat pheromone diffusers and Purina Pro Plan Calming Care probiotic powder, for both your resident cat and the kitten. These can improve their ability to manage the stress of the introduction process. 

2. Scent Swap

After your kitten has settled into their new home for a few days and both cats seem to be calmly sniffing at each other under the door, begin the process of scent swapping. This involves taking something with the new kitten’s scent (such as a toy or blanket) into the resident cat’s area and vice versa.  

Allow them to smell each other’s scent. The goal is for both the cat and the kitten to be around each other’s scent without showing any signs of stress, such as: 

• Hissing and growling 

• Tense body posture 

• Raised hackles 

• Flat ears 

• Dilated pupils 

• Rapidly swishing tail 

Rather, look for relaxed body posture, a tail held straight up or with a slight curl at the tip, flat fur, and upright and forward-facing ears.  

3. Room Swap 

Room swapping is when you allow each cat time in the other’s space without the other cat present. You can start with room swapping for about 15 minutes per day and increase the sessions until both cats seem relaxed being in the other’s area.  

When both cats seem comfortable with each other’s areas for a decent amount of time, perhaps an hour or two, move on to the next stage.   

4. Allow the Cats To Play Near Each Other

Install a barrier between the two cats so they can see each other but not physically interact. A useful option is a full-length gate, such as the Richell Cat Safety Gate, which prevents either cat from leaping over the barrier. 

Play with the cats, one at a time or simultaneously if you have a second person with you, keeping the cats in view of each other and using a feather wand or another interactive toy.  

If both cats seem interested and content playing around each other, gradually increase the length of these sessions until they’re able to play near each other for about 15–30 minutes at a time.  

5. Supervise Meetings 

When the cats can play well near each other, or at least seem calm when making visual contact with each other, allow them brief, supervised meetings nose-to-nose without a barrier.  

Starting with just a few minutes at a time may be helpful. As before, gradually lengthen the duration of these meetings as both cats tolerate each other’s presence.  

6. Introduce Unsupervised Time Together

When the cats have had several consistently calm, aggression-free meetings that last for at least an hour, you can begin to leave them alone together for short outings, such as running errands.  

At the start, it can be helpful to set up a pet camera to monitor their interactions while you’re gone, so you can intervene if you notice any signs of stress or aggression.  

Make sure that each cat has their own food and water bowls, toys, cat trees, beds, and at least one litter box per cat so that there are sufficient resources to prevent territorial behavior, which can trigger fights or increase stress and tension.  

With the right approach, your new kitten and resident cat will coexist peacefully for years to come.