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San Diego Humane Society

Introducing Cats

There is no “one size fits all” approach to introductions. Some cat introductions go very smoothly, while others may take a few weeks or months before they learn to tolerate one another. The best thing to do is to go as slowly as needed. We all want our cats to get along quickly, but remember that this is a long-term relationship! Patience will pay off, and rushing may have adverse effects.

Help Your New Cat Settle In

  • Provide a safe, enclosed space (such as a spare bedroom) with litter box, food, water, toys and a place to hide (a cat carrier with a towel inside works great!).
  • Let your new kitty become comfortable there for a few days. Avoid having your other cats enter the room or interact with them at this time. It is completely normal for your resident cat to be curious and sniff under the door.
  • Swap bedding and other items that have your new cat’s scent with similar items that have your resident cat’s scent. This allows both cats to get accustomed to the other’s scent without meeting face-to-face.
  • Spend quality time with each cat on either side of the door. Again, this allows the cats to be aware of each other in a non-confrontational and non-stressful situation.
  • If at any point either cat is hissing intensely or growling, continue to keep them separate for as long as it takes the upset cat(s) to settle down. Other signs of stress are: not eating, inappropriate elimination (not using their litter box), over grooming, etc. This may mean that the separation needs to last a week or more. If either cat’s reaction is more intense than you feel is normal, please call our Behavior Helpline at 619-299-7012, ext. 2244.

Begin Face-to-Face Intros Slowly

  • If there is no intense hissing from either cat (i.e. loud hissing with wide open mouth and teeth showing, or multiple hisses), prop the door open just about an inch to allow the cats to view each other without being able to make contact. Leave the door like this for a few days. Carefully monitor their interactions. If no serious hissing or aggression is noted, then it’s time for the next step.
  • EXTRA STEPS FOR A SHY KITTY: It’s important to take introductions very slowly if the new kitty is shy. She will need extra time to settle into her new environment and feel safe. It may be necessary to repeat the introduction and separation cycle several times. This separation time is also a wonderful time for you to bond with each cat, one at a time, so they do not over-bond to each other.
  • Open the door and allow the cats to interact on their own time. Do not force the cats to meet or to go into the other’s space.
  • Continue to monitor their interactions. At first, let them interact for 10 to 15 minutes at a time. Then separate them again. Do this several times a day until you are sure they are tolerating the presence of each other, and not fighting, chasing or watching the other cat intensely. It’s important that you do not leave them alone together until you are reasonably certain that they will not hurt each other. If you’re not sure, err on the side of caution and keep them separate.
  • Sometimes it can be helpful to distract the cats with toys, but ensure to keep the toys at least four feet apart. Sometimes cats can be so distracted by a toy, that that they forget to be upset about the other cat. Depending on the personality of your cats, this method may not work and the toys may create a rivalry. Carefully watch these interactions to ensure neither cat is becoming stressed. Sometimes giving treats to both cats — when neither is hissing — can distract and alleviate the situation.

Most cats will adjust to living within a multi-cat household. Like people, some will enjoy it more than others. Patience is the most important factor to ensuring you’ll have harmony in your home.

Behavior Helpline: Contact our Behavior Team

For behavior questions, please contact our Behavior Helpline either by calling 619-299-7012, ext. 2244, emailing or filling out our Ask a Trainer form. San Diego Humane Society Adopters can fill out the Post Adoption Consultation form to schedule their troubleshooting session. We aim to respond within 7 days, but responses may take up to 2 weeks. Thank you for your patience!

Note: Due to the potential for serious injury, canine and feline aggression are best handled by a professional who specializes in aggressive behaviors. Because phone or email counseling is inadequate for addressing serious behavior concerns, we ask that you contact a qualified professional for help. Please refer to the list of behavior resources here.

Questions About Public Classes

San Diego Humane Society offers training classes and resources to address a variety of needs for companion animals.

Our training philosophy is based on the behavioral science concepts of positive reinforcement. Training your pet using these concepts will not only help them learn new behaviors more quickly, it will also strengthen the bond you share.

Our website includes a current schedule of training classes or call 619-279-5961. 

View Training Classes   Gift a Training Class


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