Introducing Your Cat to a New Cat


If you’re bringing a new cat into your home, the most important thing is to be patient. The introduction between two cats must be gradual and it can take a long time for a relationship to grow. The first impression a new cat makes when they meet your resident cat is critical. If two cats display aggression during their first meeting, this may set the mood for their future relationship.

If your resident cat becomes aggressive when she sees other cats outside your home, you’ll probably have a difficult time introducing a new cat into your household. If your cat has lived harmoniously with other cats in the past, the odds are good that she’ll adjust to a newcomer. However, it is generally not possible to predict whether or not any two individual cats will get along. In order to set them up for success, be patient and follow the below steps.

Step 1: Keep the Cats Separated

Just before you bring your new cat home, confine your resident cat to one room so the cats are unable to see each other.  Do not give your resident cat an opportunity to approach the new cat in their carrier. This can be extremely frightening for the new cat.

Bring your new cat directly into their own quiet room. Be sure the door to this room stays closed. This will allow the two cats to smell and hear—but not see or touch—each other. This helps reduce stress by not overwhelming either cat with too much change too quickly. 

Each cat should have essential items within their respective spaces: food, water bowl, litter box, scratching post and places to hide (cardboard boxes make for easy and inexpensive hiding spots). Do your best to avoid changing your resident cat’s environment and routine as much as possible: keep the same feeding schedule, avoid moving resources such as litter boxes or scratching posts, and give them plenty of your attention.

During this period of separation, teach the cats to associate each other’s scent with positive experiences:

  • Feed the cats treats near the door that separates them so they learn that coming together (even though they can’t see each other) results in a pleasant experience.
  • Offer each cat something that smells like the other cat, such as bedding or a towel rubbed on each cat’s head and cheeks. Place a treat on the bed or towel to help the cats make a positive association with the other cat’s smell.
  • Play with each of the cats near the door. Encourage them to paw at toys under the door. Eventually the cats may play “paws” under the door with each other.
  • If your resident cat is not showing signs of stress and your new cat is exploring confidently, eating well, and using the litter box, switch the cats’ locations so they can investigate each other’s smell. This also allows your new cat to explore a different section of your home.
Step 2: Let the Cats See Each Other

Only move onto this step if there are no signs of aggression (hissing, growling), both cats are eating well, using their litter box, and otherwise not showing any signs of illness or stress. Remember to take it slow! You are helping the cats to build a relationship that will continue to develop over time; there is no need to rush them—different cats go at different paces.

Before you start, decide if you will use a baby gate for this step or just crack the door open slightly. Your goal is to allow the cats to see each other, but not interact. If you use a gate, be sure it is securely in place before opening the door. Use this method with caution because a cat can easily jump over even a tall gate.

  • If possible, have a friend or family member help, where one cat and one person are on each side of the door. Give each cat a play session followed by a meal before you start.
  • Allow the cats to see each other. When either cat notices the other, offer that cat a tasty treat or play with a favorite toy. Do not force the cats to come closer to one another. It is important that the introduction goes at their pace.
  • Avoid petting or holding either cat during these sessions. Being petted or handled can inadvertently cause stress and they could accidentally scratch you.
  • Let the cats see each other for just a few minutes and end each session while both cats are still relaxed. Continue to keep the cats fully separated between these sessions.
  • Over the next few days, continue to feed meals, offer treats and play with the cats near the barrier. Gradually lengthen the amount of time the cats see each other.
Step 3: Let the Cats Spend Time Together

Hold off on this step until the cats are completely relaxed during Step 2 and show no signs of conflict or aggression. Supervise these initial face-to-face interactions carefully and keep the interactions short at first.

  • It is a good idea to play with each cat while they can see each other behind the barrier, feed them a meal, and then remove the barrier. This is so that both cats are feeling calm when they spend time together.
  • Start with just a few minutes at a time, gradually increasing the time they spend together over several sessions. Carefully observe both cats for signs of stress and do not force them to approach each other.
  • As the cats become more comfortable with each other, allow them longer and longer periods of time together.
  • Keep a large towel handy just in case the cats begin to fight. If they do fight, do not touch them! Use the towel to block them from seeing one another then lure them away from each other. Go back to Step 2 for about another week then try removing the barrier again.
Additional Tips for Keeping the Peace in a Multi-Cat Household
  • Your cats will be more likely to get along if they’re happy in their environment. Look at the layout of your home. Make sure there are always plenty of hiding spots for your cats. Some like to sit up high, on shelves or perches while others tend to hide under and behind things, so make sure you provide hiding spots at floor level as well.
  • Offer at least the same number of litter boxes as there are cats but ideally one more (so if you have three cats, offer them all access to at least three litterboxes but four is better). The litter boxes should be located in different areas of the home as opposed to side by side.
  • Offer multiple scratching posts, resting/hiding spots, water bowls, feeding stations and perches, spread out in different locations. When cats have to compete for resources, it can increase the potential for conflict. It is especially important that food, water and litter boxes are placed out in the open so your cats don’t feel trapped or vulnerable when they access these resources.
  • In addition to a well-designed home environment with plenty of access to resources, consider using a pheromone therapy such as Feliway® Multi-Cat.  Available as a diffuser, this product is a copy of the feline appeasing pheromone mother cats produce during lactation and can provide a calming effect among the cats in your home.
  • If you’re bringing a new cat into a household with multiple cats, introduce each resident cat to the newcomer individually. After each of your cats has met the new cat one-on-one and absent any signs of stress or aggression, you can start to allow all of the cats to mingle as a group.
  • When returning from a vet visit, even if just one of your cats went to the vet, it is always a good idea to keep the cats in separate rooms for at least a day. Smell is a key form of communication for cats and the smell of the vet practice can be interpreted as threatening.
  • If one cat spends most of their time hiding or one cat continuously bullies the other cat, reach out for help. These types of interactions can cause other behavioral issues, such as litter box accidents, and the longer these behaviors happen, the harder they can be to fix. See below for our contact information or look for a certified professional.

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