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When Will My Maine Coon Be Fully Grown?

Maine Coons are perhaps best known for their size. Their commonly applied nickname is the ‘Gentle Giant’, but do they all end up as giant cats?

Like people, Maine Coons can vary widely in appearance and size, and having owned this breed of cat for over 25 years, I can definitely vouch for this.

When do Maine Coons stop growing?

Maine Coons get really big compared to many other cats! They dwarf the average household cat and can literally grow to double their size.

When is a Maine Coon likely to be fully grown? Whereas most cats are fully grown by 24 months, a Maine Coon will grow and grow until it’s about 4 years of age. Though they are considered adults at one year, Maine Coons are definitely not full-grown cats at this age.

The average weight of a mature male Maine Coon is usually 11 to 18 pounds whilst females are generally lighter at 8 to 12 pounds.

Maine Coon kitten compared to an adult Maine Coon

A male Maine Coon is usually significantly larger than a female – the female Maine Coon usually maxes out at around 12 pounds whereas the male on average will weigh no more than 18 pounds.

Occasionally, heavier Maine Coons feature in the news and on social media. Some are just naturally larger than average, which happens with humans occasionally too.

It is unusual that the Maine Coon will grow larger than this and if it does it is more likely to be down to an unhealthy diet and they are overweight (fat) – which for a cat like this can pose several health risks.

An important point to remember here is that not all Maine Coons are large. Yes, they are a breed that can produce particularly large cats but just as many are pretty average-sized.

Take our two (picture of them above at age 14!) – they’ve never been the biggest of cats and they both weigh around 12-13 lbs, for males – that’s kind of in the middle somewhere.

It’s not just the weight of Maine Coon’s that tends to be large, their height and length are often huge too – in fact, the longest cat ever recorded was a Maine Coon which was over 4 feet in length! This isn’t too far off the height of Kylie Minogue!

When does a Maine Coon stop growing?

A Maine Coon will stop growing at around the age of 3 or 4 years old. There are a few factors that affect their growth rate, eventual size, and at what point they stop growing.

It’s mostly down to genetics, which means the size your Maine Coon will reach is not something you can really control.

Health is more important than size

I hope that no one actually buys a Maine Coon just because it might end up being an exceptionally large cat. There is so much more to this breed than just its appearance.

Often though, people will initially discover this breed through images shared on social media and decide there and then that this is the cat for them.

Their good looks and size may be the reason why so many people first buy one of these, but it is not the reason why people fall in love with them.

The Maine Coon’s personality is what keeps people devoted to this breed, including me. I love cats, all of them, but there is no reason why I would ever choose another breed other than the Maine Coon.

They are an intelligent, mischievous, fun-loving breed that craves human attention. This is not your typical feline.

They crave human attention and although they are not categorized as a lap-cat they will want to spend the majority of their time in your company.

If you can’t offer them this attention then there are plenty of cat breeds that will suit your lifestyle a lot better.

Something very important to remember is that you, as an owner, have little to do with how large the Maine Coon will eventually become.

Don’t think by feeding them more than they need will increase their size – it will not! Overfeeding your Maine Coon will only serve to increase their weight, certainly not their size.

They will become overweight and this can have serious health implications in cats – it is a guaranteed way to keep them from having a long, happy life.

When Will My Maine Coon Be Fully Grown?
Harry and Charlie

Balanced diet for your Maine Coon

What is required though is a simple, balanced diet. Don’t think, because you’ve seen it in cartoons, that your Maine Coon should have milk!

Cats are lactose intolerant and they will end up with stomach problems if you go down this route. Actually, kittens still have the enzyme they need which breaks down the lactose but adults lost his ability.

What we do is keep things relatively simple and have a mix of sachets of food, dried food and in the evenings they both get some plain fish.

We’ve been pretty lucky with ours but we don’t insist on them eating what is in front of them or they don’t eat. We change things around now and again just to keep things interesting for them.

Sometimes, they just turn their noses up and what we give them, despite the fact that they’ve eaten it perfectly fine for ages.

So, we change it – some people might call this ‘spoiling them’, but really – how hard is it to change the type of food you give your cat?

Life’s too short, give your Maine Coon food they like to eat, not have to eat.

We’ve never really done the whole raw-food route. Some people swear by it, others don’t.

Opinions are definitely mixed and not just among owners. If you ask vets for their professional opinion it seems to be equally split.

Personally, if I was going to use it, it would only be to mix this up occasionally. For instance, young chickens do contain a lot of energy that could help your Maine Coon grow.

Interestingly, I’m on a few social media groups purely about the Maine Coon and it’s obvious that feeding them raw food is a lot more common these days than it was just a few years back.

Also, those doing it seem to have quite a bit of success – so maybe it is something to consider. As ours are now 14, it’s perhaps a little late to look into for us.

What do we mean by ‘maturity’?

When Will My Maine Coon Be Fully Grown?

We hear this term frequently when talking about cats and their growth, but what do we actually mean by it?

Maturity, when discussed in relation to felines, means the point where full development has been reached.

As we have already said, this can vary a little between individual cats but in the Maine Coon, you may see growth in its size up to around 4 years of age.

There has been some discussion recently as to whether neutering a Maine Coon at an early age can have a detrimental effect on its overall size.

I’ve tried to find evidence to back this up but have found nothing in any official scientific publications to corroborate the idea.

When Will My Maine Coon Be Fully Grown?
A rare cuddle between brothers, Charlie (left) and Harry.

Big Cats and Small Cats

If you want to give yourself the best chance of ending up with a larger size of Maine Coon then the best work you can do actually takes place prior to buying the kitten.

Be sure, if possible, to buy from a reputable, recommended breeder whose Maine Coons are thoroughbred.

These breeders should be registered with a known organization, an example would be with the Cat Fanciers Association (CFA).

There are a couple of real, genuinely good reasons why you should consider purchasing your Maine Coon from a breeder:

  • Healthier – it is in the breeder’s interest to ensure that your future Maine Coon is in the best possible health. The breeder should only breeder with cats that don’t have any genetic health concerns, so therefore, your new kitten should be free from these also.
  • Vaccinations – More than likely your new kitten will have had all their vaccinations completed by the time you come to collect them. This reduces some of the cost and a lot of the hassle in having to do it yourself.

The downside though, and perhaps the only downside to purchasing your Maine Coon through a breeder, is the cost.

Yes, you will pay more of course if you use a good breeder than if you don’t. But, what you’re buying is confidence – confidence that you will have a higher chance of receiving a healthy cat.

You may be wondering what all this has to do with the size of the Maine Coon?

Well, buying through a breeder is perhaps the best way to ascertain what the eventual size of your Maine Coon will eventually be. How? Simple really…

Can I predict how large my Maine Coon will grow?

Yes, the best way to predict how large your Maine Coon will be is to look at its parents. This is why buying through a breeder is such a good idea if this is what you’re particularly interested in.

The breeder should be more than happy to show you the parents and if they don’t have them both in the home (which can be quite normal) then they will at least be able to show you pictures and provide you with details such as how large they are.

I said this was the best way to predict how large they will become – it’s actually also the only way to predict their eventual size.

The Maine Coon’s growth rate can vary so just because they are small after a year, doesn’t always mean they will end up small.

Breeding Programs

There are some breeding programs that may offer extreme-sized Maine Coons, essentially telling you that they will guarantee you a huge cat when they reach maturity. I would advise you to steer well clear of these.

These breeders do not follow best practices. Some of these cats are crossed with other non-Maine Coon breeds and the priority for the majority of these breeders is 1) Size and 2) anything else.

Conclusion – When will my Maine Coon be fully grown?

Maine Coons are known for being large, but not all of them actually are. However, even small Maine Coons are pretty big compared to other cats!

This cat should not be bought just because of its size. It has so much more to offer than that.

You won’t find a more fun, cheeky, weird, playful breed of cat and it has been an absolute pleasure living with the Maine Coons I’ve owned over the last quarter of a century.

Remember, good health is far more important than good looks and size. At least that’s what my wife keeps telling me…

The Complete Guide to Maine Coons, packed with images and information, is a great read for a new owner.

When Will My Maine Coon Be Fully Grown?
Our son Joe with Charlie

Here are some of my favorite products for cats

Thank you for taking the time to read this article. I hope you found it helpful whether you own a cat or are considering it. I thought I’d share a few of the cat products I love which you might find really useful too.

The following are Amazon affiliate links, and if you decide to use them, I’ll earn a small commission from Amazon at no cost at all to you.

An indoor cat tree: This is an excellent item to satisfy a cat’s urge to climb and scratch. There are several sizes to choose from so you can pick the right height for your home. Our cats love this Amazon Basics tree with multi-levels, scratching posts, and a little hideaway.

Fred and Oscar in their Amazon Basics cat tree

Drinking fountain: Cats love to drink from flowing water. Many don’t seem to drink enough so a fountain is a good way to get them interested. This Orsda Fountain is quiet, has a large capacity, and looks stylish too.

Scratcher Lounger: The more cat-scratching posts you have the better. Many cats like to claw horizontally which is why we chose the PetFusion Ultimate cat scratcher. It has seen quite a bit of action from 4 Maine Coons but still looks great.

This article may contain affiliate links; if you click on a shopping link and make a purchase I may receive a commission. As an Amazon Associate, I earn from qualifying purchases.