How To Introduce A New Kitten To Your Cat

It doesn't have to be the worst day of your cat's life 🙀

how to introduce kitten to cat

All you want when you bring home a new kitten is for him to become BFFs with your current cat.

Nothing would make a self-described crazy cat parent happier, after all.

But you’re going to need to know how to properly introduce them if you want that Disney magic to kick in.

The Dodo spoke with Dr. Andrea Y. Tu, medical director at Behavior Vets in New York City, to get some tips for making sure their introduction goes smoothly — and what to do if it doesn’t.

How to introduce a kitten to your cat

The key to kitten introductions is to do them gradually.

“You want to do it slowly,” Dr. Tu told The Dodo. “Take your time and really have a space set up where they’re separated from each other most of the time.”

You have to remember that the kitten is new to your entire home, not just your cat.

So separating your kitten in a smaller room (like your bathroom) will help him get used to the new space, while also getting used to your new cat from a safe distance.

“When you bring a new kitten home to a household that already has a cat in the house, those cats may not meet for the first week,” Dr. Tu explained. And it’s totally OK if it takes that long! “They may not lay eyes on each other,” Dr. Tu said.

Getting used to each other’s smells is a very important part of the introduction process for both the cat and the kitten, whether it’s through scent transfers (more on that below) or sniffing under the door.

“If you’re seeing a lot of hissing … you’re going to separate [even more] so there’s no direct access, but the smells are going to be permeating through the house,” Dr. Tu said. “So they’re going to recognize there’s another cat in the house, but not to the intensity where they’re hissing and stressed out about it.”

Tip: Scent transfers

Scent transferring is a totally contactless way of getting your kitten and your cat comfortable with each other’s smells.

“One of the things that I often will tell people to do, even when their cats are separated … is you can take a small hand towel, wipe down the kitten and then take that towel that now has the kitten’s scent and wipe down the resident cat so you’re transferring scents,” Dr. Tu explained.

You would then do this the other way around (wiping down your resident cat and bringing that towel to the kitten) to transfer scents both ways.

“[You should] do this several times a day,” Dr. Tu said. “Their scents [will start] to commingle and [they’ll start] to recognize [that the other cat is part of their household].”

Tip: Playpen separation

“In the case of [introducing a cat to] a kitten, if your cat has not shown really overt aggressive signs, you could do things like separate them by a playpen [so they can see each other but not interact],” Dr. Tu said.

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With the playpen strategy, you’ll put the kitten in the pen and let the cat roam around the room so they can get used to each other on a visual level, while still having safe boundaries.

This helps by:

  • Gradually introducing the kitten to his home
  • Increasing the intensity of the introduction
  • Preventing any aggression injuries

“They can see each other moving around, and they really are starting to smell each other,” Dr. Tu explained.

How long does it take to introduce a kitten to a cat?

There’s no exact time frame for the introduction process, since it really depends on how your cats are reacting.

“Sometimes that first period where they’re completely separated and you’re doing scent transfers could take a few days,” Dr. Tu said. “And the next three to five days would be them sniffing each other under the door.”

Once the separated sniffing is going well, you can move on to playpen introductions.

“If they seem like they are not stressed or hissing at each other, then you can progress to the next stage,” Dr. Tu said.

“You may do these supervised visits for another week or so, and then you can also structure in feeding in the same room for another week or so,” Dr. Tu explained.

And once they’re comfortable with that, they can finally meet face-to-face!

Just know that it might be a while before that actually happens.

The general timeline really varies,” Dr. Tu said. “It could be a few days at each step, or a few weeks, making the total process potentially months long … Always assume it should take longer than you think, no less than about 5 to 7 days at each step.”

That’s because the last thing you want to do is move things along too quickly.

The biggest mistake people can make is to rush things, because if there is a bad interaction between the two cats, it's going to take that much longer to get them to accept each other,” Dr. Tu explained. “Or, the interaction could be bad enough that it makes them never accept each other!”

Regardless of how well it’s going, the introduction process is still going to be very gradual and take some time.

Things to look out for when introducing a kitten and a cat

You’re going to want to keep your eye out for signs that your kitten and your cat are not clicking.

These signs include:

  • Hissing
  • Swatting
  • Ears going back or flattening

If you noticed any of these things, you’re going to want to talk to your vet or behaviorist right away, because problems within cat relationships are kind of a big deal.

“In inter-cat issues … you want to act fast and early, because once it’s set in, it really is hard to turn it around,” Dr. Tu explained.

In addition to seeking professional help in these situations, Dr. Tu recommends getting a cat pheromone diffuser (specifically designed for multi-cat households) to help keep your BFFs calm.

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