When Will My Cat Stop Hissing at Our New Cat?

If you’ve introduced a new cat into the home and they’re still not getting along with your other cat after days, weeks, or more, you’re not alone.

One of the common questions I hear a lot is – when will my cat stop hissing at our new cat?

It can be distressing and stressful for you and your cats if they are hissing at each other behaving aggressively.

Once you understand why they are hissing at each other, or why one of them is, it can be quite easy to solve however – so don’t panic.

In this article, I’ve summarised some of the reasons why cats don’t get along when they are introduced into the same home. Along with some of the things you can do to resolve it.

So, while all cats have their own unique personalities and quirky behaviors, I have no doubts you can create a harmonious home for everyone with a little time and attention to their needs.

Why Do Cats Hiss at New Kittens or Cats?

Introducing a new cat or kitten to the home is always an interesting experience. Your ‘old’ cat, the one that already lives there, is rarely going to welcome them with open arms.

The usual reaction is to hiss, growl, snarl, be standoffish and stare, and perform any other passive-aggressive behaviors they have.

This is largely because they view any new cats as potential threats entering into their territory. It’s a complicated dynamic, there are some other reasons as I’ll explain:

They Feel Threatened – When a cat feels threatened they will arch their backs, raise their fur to make them as big as possible, and hiss at the threat.

As long as this doesn’t turn into a physical confrontation or your cat is too stressed by the situation this will subside when they realize there is no real threat.

They Are Being Territorial – Cats are territorial animals, they like to patrol what they see as theirs and keep other cats out of their space.

Adding a new cat into the home means they will need to learn to co-exist. Something almost no cats as happy at about at first, but one they all come to accept in time.

There Is a Large Age Gap – The age of the cats you’re introducing can make a difference to how well one, or both of them are willing to accept the other.

Older cats are generally less welcoming of younger cats with a lot more energy and activity, and vice versa.

It’s a Gender Issue – A neutered male cat is generally the most relaxed and accepting of new cats.

Putting two females or two unneutered males together can often cause fireworks at first. Something to keep in mind if you have some choice over the gender.

How to Introduce a New Cat into Your Home

I could write a whole chapter on the ways and techniques to introduce different types, genders, and ages of cats into a home so it goes as smoothly as possible.

However, for the purpose of this article and addressing the main reasons why your cat is still hissing at a new cat here are some of the things you can try to help them both get along better together:

Keep the New Cat in Their Own Room – If you have a spare room then you should use this to home the new cat for a few days.

Put everything they’ll need in there. A litter box, food and water bowls, a comfy bed (that they probably won’t use), scratching post, and so on.

This will lower their anxiety, help them become comfortable with you at their surroundings, and allow your other cat to get used to their scent without seeing any danger.

Swap Their Scents – Cats need to be comfortable with having each other’s scents in the home if they are going to share the space.

The best way I’ve found to do this is to swap their beddings. Or at least put a towel from each bed into or near the other cats.

Start Letting Them Mingle – After a few days of being aware of each other and becoming more familiar with each other scents you can introduce them.

I usually do this by feeding them at opposite ends of a room. This way they have something to focus on while in each other’s presence.

This is an important part of the process. Stay at a distance and keep an eye on how they behave. There should be a lot less hissing than when you just introduced them straight away if that’s what you tried.

If there is still friction put the new cat back into their room. If not, try leaving the door open and letting them investigate each other in their own time, with a place to go back to safety if needed.

My Cat Is Hissing at Me Because of New Kitten

Your cat will often act like they are upset at you too when you bring a new cat into the home. Don’t take this personally, in my experience it’s really not the case.

It’s more likely that your cat is upset because of the new cat entering the home and they are in a mood. Not with you personally, but you’re going to be in the firing line.

Just follow the steps above to introduce a new cat properly and they’ll be back sitting on your lap, weaving in and out of your legs, or doing those things they used to do to show you how much they love you.

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While it can be a complicated and timely process inforcing a new cat into your home and seeing an end to all the hissing and standoffish behavior, with the tips in this article and some patience I have no doubt you create a happy home for all.

Like I mentioned earlier on, I’ve never met a cat that didn’t eventually settle in and go on to live happily with other cats. They may not become best friends, and it may take days, even weeks, but you’ll get there.

Good luck, and if you have any questions please feel free to drop a comment below.