How to introduce a new cat to your cat
You have one cat and you’re completely in love. If you could multiply that feeling, you would. You think, if one cat makes me feel this way, how would a second cat make me feel?
Or maybe you work outside the home. You watch your cat watching you when you leave in the morning and wonder if your cat is lonely all day. You might not have been planning to get a second cat, but you think that maybe your cat needs a friend.
Here’s what not to do: just head on over to the shelter, pick out a wonderful new cat and bring him home to meet your resident cat, thinking that he’ll think the new cat is wonderful, too.
Introducing a new cat to your cat takes forethought, planning, and patience. And a little bit of luck, too.
Does my cat need a friend, or would I make my cat’s life miserable by bringing home another cat?
This is actually a trick question. Yes, cats are social, but they’re also not social, at least in the way we think of social animals being social.
According to the Merck Veterinary Manual, “Cats are social animals that, in feral conditions, live in groups consisting mainly of queens and their litters.” What this means is that when cats are left to themselves, they do live in social groups, but their groups are made up of family members. Family members can choose to leave the group, but the group doesn’t typically welcome newcomers.
One of the other differences between feral cats and, say, feral dogs, which we immediately consider to be social animals, is that free-ranging cats hunt alone, scavenge alone, and eat alone. They really aren’t looking for company when they are engaged in those activities. Cats typically have wide territories and actively avoid contact with other cats who don’t belong to their family group. This is their natural behavior.
As small as they are (no matter how big they are) our homes become our cats’ territories and they don’t easily welcome “outsiders” into their home range. To make matters worse, we inadvertently do things that make it harder for unrelated cats to coexist harmoniously, like throwing two unrelated cats together, and then expecting them to eat out of a communal food dish, or use a litter box situated in the corner of a tight bathroom.
How do I know if my cat would welcome another cat in my home?
In short, you don’t know until you try if you will ever be able to successfully introduce a new cat into your household. You could invest eight months or even a year in the process, doing everything right, but the cats will have the last word. After all that time and work you might still have to end up rehoming one of the cats.
Or, you could have a great cat-to-cat experience right out of the starting gate, and end up with two lifelong fast friends and wonder to yourself why you ever worried.
What are some signs your cats might be willing to welcome a second cat in the home?
If your cat has already lived harmoniously with another cat in the past, that’s a good start. You already know that your cat can live with another cat in her space and has some social skills. A cat who has lived with another cat successfully once might be the kind of cat who actually enjoys another feline in her midst.
Playful cats often do well with another cat in the house. Cats who were socialized to other cats as kittens, especially if that kind of interaction continued throughout their lives, have more of a chance of success.
On the other hand, if your cat becomes aggressive every time a neighboring cat saunters by your yard, that might be a “less good” sign. Cats who display fear behaviors or anxiety also might not be the best candidates for a successful matchup.
The bottom line is that some cats are more social than others and some cats are more solitary. But they are all individuals and there is no way of predicting whether two individuals will get along.
Note that the more cats you have, the more likely it will be that you will have conflicts. Think about that if you already have two cats and are wondering if you should get three.
What kind of cat should I get for my cat?
The first time you went to the shelter, you picked out the cat you liked.
This time, you are looking for a cat that your resident cat will like (or at least tolerate). You are also trying to find a genuinely appropriate home for a shelter cat who desperately needs one.
Give the situation a fighting chance by choosing a cat the shelter knows has already lived with another cat, for all the reasons mentioned above, if possible. A cat who has already lived peaceably with another feline friend may still not get along with yours, but at least you’re bringing home a cat who has experience with shared spaces and resources, and who might even enjoy the company of another cat.
Next, assess your current cat’s personality. The goal is to find a second cat who will be compatible with yours.
If you have a calm cat, a senior cat, or a frail cat, do not, DO NOT bring home a kitten, no matter how tempting it is. Do not bring home a rambunctious cat, no matter how charmed you are by his antics in the shelter. It would not be fair to either cat, but most especially the new cat who may find himself back at the shelter, the last place he ever wanted to find himself again.
If you already have a young and rowdy cat, do not get a laid-back cat, a quiet cat, or a shy cat. You may look into the eyes of that frightened cat cowering in the corner of her cage in the shelter and desperately want to rescue her. But you’ll be doing her no favors by bringing her home to a circus.
Set the stage for a successful cat-to-cat meeting
There are things you should do before you bring a new cat home from the shelter to your resident cat to set the stage for a successful life together.
First, set your own expectations and be prepared for a long, long introduction process. Recognize that it can take as long as eight months or even up to a year to properly integrate a new cat into an existing cat household. They may develop a friendship or they may just learn to avoid each other. But be prepared for the potentially long road ahead. If you’re impatient, or if you think you can rush the process and everything will be “fine,” you may end up with cats who fight, and eventually have to rehome one or the other.
Understand that introducing two cats is a process. You don’t just throw them in a room together and hope for the best. Do it right and they can build a relationship that is satisfying for all the living things in the house.
Bringing your new cat home to your resident cat: what to do first
Before you even think about bringing your new cat home, bring his scent home, like an ambassador. Ask if you can bring a towel or blanket your new cat has used at the shelter back to your house. Put the scented towel near your cat’s food dish or bed. If your cat is pleasantly curious about the towel, your work, for the moment, is done. If your cat hisses or spits at the scented towel, move it away from his dish or bed and gradually move it closer, a little bit each day, until you bring the new cat home.
In a perfect world, you would also bring one of your cat’s blankets to the shelter for the new cat to sniff and explore. Understandably, shelters are concerned about the transmission of disease and many may be unwilling to allow you to bring in an item from your home. Do what you can do.
On the way home from the shelter, place a towel or some bedding the new cat has already used in his carrier so his is surrounded by something familiar on his way home. Cats feel safe around their own scent.
Whatever you do, do not let the new cat come in contact with the resident cat as you bring the new cat in the front door. Follow the steps below to improve your chances of success. Do not try to force the relationship too soon. You could end up sabotaging what might have been a happy pairing. Remember that like with people, first impressions between cats are critical so control their initial impressions of each other.
Step by step: How to introduce your new cat and your resident cat
Step 1: The new cat gets his own room
Step 2: Feeding the cats on either side of the door
Step 3: The big switcheroo
If either cat appears nervous, go right back to Step 2 and start again. Do not rush steps just because you’re eager to have both cats living together with you in your home. Rushing steps will achieve the opposite of what you really hope for.
Step 4: A visual introduction
Step 5: Allow the cats to meet
After Step 5: How to make sure that the cats continue to live peaceably together
One of the most important things to do to keep cats living peaceably together is to ensure that there is no scarcity of resources. Make sure you have enough litter boxes and that they are placed where cats can feel safe using them. The rule of thumb for the number of litter boxes is one plus the number of cats that you have. So, if you have two cats, you need three litter boxes.
Litter boxes need to be placed in open spaces, even if you’d rather they were back between the toilet and the tub in a little-used bathroom. Cats need to feel that they won’t be trapped when they are eliminating, which means that they need an escape hatch if they’re ambushed. The same goes for food bowls, which also need to be out in the open and preferably separated from one another.
Aside from separate bowls and litter boxes, cats need separate beds, and at least two of every special toy.
Watch for signs that things are turning sour. Is one cat the “gatekeeper” who refuses to give the other cat access to the food or water bowls? Do you notice that one cat seems to be avoiding certain areas in the house?
Do not punish cats for acts of aggression. You would be punishing them for a natural, normal cat behavior, and punishment will never improve the relationship between your two cats.
When should I call a behaviorist or my vet if my cats aren’t getting along?
It’s gone too far when:
- There is prolonged fighting between your cats, or injuries sustained from fighting
- One cat stops eating or using the litter box
- One cat begins spraying in the home
- One cat spends his life hiding
Do not wait for things to get worse: call your veterinarian or a cat behaviorist as soon as possible.
A final thought about introducing a new cat to a multi-cat household
The steps above describe the ideal way to introduce a new cat to a single resident cat. If you have a multi-cat household the steps are the same, but you must introduce the new cat to each individual resident cat separately. All of the cats should not intermingle until each cat has had successful one-on-one time with the newcomer.
 Landsberg, Gary M., et al. “Social Behavior of Cats - Behavior.” Merck Veterinary Manual, Merck Veterinary Manual, May 2014, www.merckvetmanual.com/behavior/normal-social-behavior-and-behavioral-problems-of-domestic-animals/social-behavior-of-cats.
 Gormly, Kellie B. “Do Cats Get Lonely Or Are They Fine Without Other Cats?” Catster, 13 Apr. 2020, www.catster.com/cat-behavior/do-cats-get-lonely-do-cats-need-other-cats.
 “Introducing a New Cat.” Best Friends Animal Society, resources.bestfriends.org/article/introducing-new-cat.
 “Introducing Cats to Cats.” American Humane, Aug. 2016, americanhumane.org/fact-sheet/introducing-cats-to-cats/.