How to Introduce Cats

PetMD Editorial
By PetMD Editorial on Feb. 23, 2016
How to Introduce Cats

Reviewed and updated for accuracy on March 30, 2020, by Dr. Manette Kohler, DVM

If your cat has gotten along with another cat at some point in her life, you might assume that she will accept any new cat with no hissing or howling. Unfortunately, cats are territorial animals and will not welcome just any feline into the family.

Introducing cats requires patience and sensitivity, so you should prepare for it to take some time for two cats to accept one another.

Here’s some advice on how to find a new cat that your cat will accept and how to introduce them.

How to Find the Right Match for Your Cat

Like finding a roommate or partner, matching up cats requires an understanding of what makes each creature tick. Consider your resident cat’s personality, and look for a cat that’s similar in personality and energy level.

“The more you can get cat personalities to match, the better,” says Megan Maxwell, a certified applied animal behaviorist in Blacksburg, Virginia. “Cats that are similar in personality are more likely to hit it off. A playful cat is a good match for a playful kitten.” And that lively kitten may clash with a calm, older cat.

How to Introduce Cats

Fortunately, the first introduction does not have to be negative. As you prepare to introduce your cat to a new addition, keep the following steps in mind.

Don’t Rush the Introduction Between Two Cats 

Before you bring your new cat home, prepare yourself for the introduction. The initial introduction is important, since it can make or break the relationship, says Pam Johnson-Bennett, certified animal behavior consultant.

“For both cats, abrupt introductions will cause them to go into survival mode, and they will start out their relationship being hostile toward each another,” Johnson-Bennett writes in her book, Starting from Scratch: How to Correct Behavior Problems in Your Adult Cat. “While in some cases, that hostility may ease as time goes on, it more often sets the tone for the relationship from that point on.”

Start By Keeping Them Apart

When you bring your new cat home, place them in a room that’s not your resident cat’s primary space. Keep both animals isolated so that they can’t see one another, preferably with a solid door between them. Make sure each cat has their own food, water, litter box, and scratching post.

Before introducing the cats, make sure they are both relaxed and adjusting well to the situation. At first, the cats may sniff one another under the closed door, which can help them get used to each other in a nonthreatening, nonvisual way. 

You can start to create a positive association by placing their food bowls far enough away from the closed door that each is comfortable and relaxed on their own side. If this is several feet from the door, gradually move the bowls closer to the door until they are very close to it.

This might take several days or more, so don’t rush the process.

Use Scent Transfer to Help Your Cats Get Comfortable

Transferring each cat’s scent to a sock and swapping them will safely allow each cat to become accustomed to the other cat’s scent.

Wipe the resident cat’s face, especially the mouth and cheek areas, with a sock, and place it in the new cat’s area. Then wipe the new cat’s face with a different sock and place that in the resident cat’s area. The following short video, by Johnson-Bennett, describes this process.

Give Your New Cat Some Alone Time to Explore

Your new cat needs to be able to safely investigate the rest of the home. This will help them feel more secure in their new surroundings.

Twice a day, with your resident in their room, open the door to the new cat’s room for an hour. This will allow the new cat to explore on their own terms and learn about their new environment.

In doing so, your new cat can deposit their scent (as it walks about and rubs on items) and also encounter the resident cat’s scent.

This is nice extension to the scent swapping that was started with the sock.

Make sure each cat is relaxed and calm before moving on to the next step.

Bring Them Together With Positive Reinforcement

Put a tall baby gate in the doorway of the new cat’s room and cover it, leaving a few inches uncovered at the bottom. A temporary screen door, partially covered, can also be used in the doorway.

Several times per day, feed each cat treats for just a few seconds with the resident cat across the room from the gated doorway.

“They get a quick peek at each other, and they are rewarded for it,” says Matthew Wildman, pet care issues manager and resident cat expert at The Humane Society of the United States. “It’s got to be a treat that each one really loves, or it’s not going to be a positive experience.”

Continue this daily until the cats are relaxed and not reacting to each other’s presence when they see one another. Then uncover more of the gate so they can see each other better, and continue in this gradual fashion until the gate is entirely uncovered.

Mealtimes can be fed this way, too. Close the door after each session. Gradually increase the time the cats are exposed to each other, and gradually move the treats or food closer to each side of the gate.

The goal is to get the cats to associate each other with good things like treats and food. You can also try petting and brushing, depending on the cats’ likes.

Encourage Playtime

Assuming things are going well, you can add in play using interactive cat toys such as prey-type toys dangling from a teaser wand.

If you’re more comfortable, you can start out with the gate still in place. There can be two people, each playing with one cat, or one person standing at the gate or between the cats, with a toy in each hand and playing with both cats simultaneously.

Keep sessions short. Always end these sessions before any negative interactions can occur.

If things are going well, increase the amount of playtime. After a while, if the cats enjoy playing and there’s no hissing, hard staring, or other hostile reactions, you can try playing with the cats without having the gate between them.

“If the cat’s laying down, purring, and casually glancing at the other cat or rubbing against the gate with her body, those are good indicators to move to the next step,” Maxwell says. It is also great to reward these behaviors with treats.

Supervise the Cats Without a Barrier

By now, if all has gone well, your cats should be eating and playing peacefully in close proximity to one another. Remove the barrier between them and let them spend time together under your close supervision.

You should, however, keep a barrier nearby; something handheld, like a large piece of cardboard. If there’s the slightest sign of stalking or hard staring, you should distract and redirect the cats by showing them the fishing rod toy or other toys or treats. Be prepared to respond quickly to any potential aggression using the cardboard to separate them.

“If you feel there’s a chance they’ll have a fight, it’s better to have a piece of cardboard to put between them if the fight breaks out rather than reaching down with your hands,” Maxwell says.

End playtime on a happy note by rewarding them with treats. You can gradually increase the amount of time you allow your cats to be in the same area together, but always keep them under close supervision.

It may take a while before you feel comfortable leaving them unsupervised. Until then, in between supervised sessions, the new cat is closed in their room, but continue to allow the new cat some private time to explore and move about the house daily (with the resident cat contained in another room).

“We want things to work out, but it may take more time than we think,” says Wildman, noting that you may have to go back a few steps in the process. “Patience almost always pays off with cats.”

If one cat hides more than usual, urinates outside of the box, or grooms herself to the point of hair loss, those are signs that she is unhappy or stressed, and you may need to spend more time working on positive reinforcement with the baby gate between your cats, Maxwell says.

If problems persist, consult a board-certified veterinary behaviorist.

By: Lynne Miller 

Image: supanee sukanakintr / Shutterstock

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