Grey Cat vs. Blue Cat: What’s the Difference?

If you’ve ever tried to describe your cat’s gorgeous grey coat and someone corrected you with, “Ah, you mean blue,” you’re not alone. It’s a surprisingly common moment of confusion for cat owners—and one that leads to a fair bit of Googling.

So, what is the difference between a grey cat and a blue cat? Are they two distinct breeds? Does “blue” refer to a specific colour? Is one posher than the other?

In this post, we’re going to demystify the grey-vs-blue cat debate once and for all—and yes, we’ll be featuring a few words about my own feline boss, Daphne (a grey moggie with very blue cat energy).

Grey Cat vs. Blue Cat: The Short Answer

Here’s the quick version:

There is no difference.

Yep, really. In the cat world, grey and blue often refer to the same coat colour—just described in different ways. “Blue” is the more formal or pedigree term used in breed standards and show circles, while “grey” is what the rest of us tend to say when we’re talking about our smoky little companions.

So, if you’ve got a grey cat curled up on your windowsill or following you into the bathroom like a tiny, furry stalker, you might technically own a blue cat—at least in terms of coat colour.

Why Are They Called “Blue” Cats?

The term “blue” comes from the soft, slatey undertones found in certain grey cat coats—especially those of pedigree cats like the Russian Blue, British Shorthair, or Chartreux. In the right light, their fur can take on a bluish shimmer, almost like moonlight on a steel surface (very poetic, very cat).

It’s a bit like how “redheads” are often actually ginger (you can read more about ginger cat personality traits here!) or strawberry blonde—naming conventions can be quirky and traditional.

In cat shows and official breed standards (such as those listed by the GCCF, the Governing Council of the Cat Fancy here in the UK), “blue” is used to describe a solid grey coat with a slightly bluish cast. It’s a nod to tradition and genetics, rather than a literal colour match.

Grey Cat vs Blue Cat: Quick Comparison

Here is a quick side-by-side look at the terminology:

The bottom line? If someone tells you your grey moggie is actually a blue cat, they are technically correct. But nobody is going to judge you for calling them grey – that is what most of us do. 

So Is Daphne a Grey Cat or a Blue Cat?

Great question—and one I asked myself when I first looked into this!

Daphne, my nearly two-year-old queen of the house, is a rescue moggie with a silky grey coat and a side-eye that could curdle milk. She’s not a pedigree or a show cat (unless “Best in Judging Me While I Clean the Litter Tray” becomes a category), so in everyday terms, she’s grey.

But technically? She could be classed as “blue” due to her solid grey colouring with no tabby stripes or patches.

If you’d like to read more about Daphne and whether grey cats have their own unique personality traits, check out my previous blog: Grey Cat Personality Traits: Myth or Reality?

Common “Blue” Cat Breeds in the UK

While grey moggies are found all over the UK (and are often seen in rescue centres), there are a few pedigree breeds known specifically for their iconic blue coats:

British Shorthair (Blue Variant)

Possibly the most iconic “blue” cat in Britain, the British Shorthair with a blue coat is chunky, calm, and built like a plush teddy bear. They’re the cat equivalent of a comfy cardigan and a cup of Yorkshire Tea.

Russian Blue

Russian Blue cats are known for their striking silvery-blue coats, bright green eyes, and calm, gentle personalities. They’re often described as affectionate but not overly demanding, making them a lovely choice for people who want a cat that enjoys company without needing constant attention. Russian Blues are also intelligent and curious, and many of them love routine, quiet spaces, and interactive playtime. They tend to form strong bonds with their favourite people and can be a little shy around strangers at first, but once they feel safe, they’re incredibly loyal and sweet-natured companions.

Chartreux

This rare French breed has a muscular body, copper eyes, and a thick blue-grey coat. They’re often described as sweet and quiet—a bit like the introvert at the party who ends up being the most interesting person in the room.

Korat

Originating from Thailand, the Korat has a heart-shaped face, luminous green eyes, and a striking silvery-blue coat. They’re affectionate and intelligent, but not terribly common in the UK.

What About Grey Moggies?

If your cat is grey but not pedigree (like Daphne), they’re simply a grey domestic shorthair or longhair. These lovely moggies come in all shades of grey—from smoky charcoal to soft dove—and may have patterns like stripes, tuxedo markings, or patches.

They’re no less regal or entertaining than their pedigree cousins—just less likely to come with a fancy-sounding breed name or a set of rosettes from the NEC Cat Show.

In fact, some of the most charming and characterful cats I’ve ever met have been moggies. Daphne, for example, is basically the Judi Dench of our household.

Can Coat Colour Predict Personality?

Not really. As explored in my blog about grey cat personality traits, there’s no hard scientific evidence linking fur colour to personality. While some surveys suggest owners perceive certain traits in different-coloured cats, it’s far more likely that breed, environment, and upbringing play a bigger role.

So whether your grey/blue cat is a calm cuddlebug or a chaotic parkour champion is less about their coat and more about who they are as a little individual. Either can be chosen as a family pet or an emotional support cat according to your needs. If you’re looking for some great grey cat names, I have some great suggestions here!

Frequently Asked Questions

Are grey cats and blue cats the same thing?

Yes, grey and blue refer to the same coat colour in cats. Blue is simply the formal term used by breeders and in cat show standards, while grey is the everyday word most pet owners use. The colour itself is identical.

Is blue a cat breed or just a colour?

Blue is a coat colour, not a breed. However, several breeds are famous for their blue colouring, including the Russian Blue, British Shorthair (blue variant), Chartreux, and Korat. These breeds have the blue coat as a defining characteristic.

Can a moggie be called a blue cat?

Technically yes, if your moggie has a solid grey or blue-grey coat without tabby stripes or other markings. In practice, most people simply call non-pedigree cats grey rather than blue, but either term is correct.

Do blue cats have different personalities from grey cats?

No. Since grey and blue describe the same colour, there is no personality difference between them. A cat’s temperament depends on their breed, socialisation, environment, and individual character rather than their coat colour.

Why do cat breeders say blue instead of grey?

The term blue comes from the soft, slatey undertones often visible in grey cat coats, which can shimmer with a bluish cast in certain light. It is a traditional naming convention used in breed standards by organisations like the GCCF (Governing Council of the Cat Fancy) in the UK.

The Bottom Line

Whether you call them grey, blue, silver, or storm-coloured, cats with these gorgeous coats have a special place in our hearts and our homes. The distinction between grey and blue is really just about context: blue is the pedigree term, grey is what the rest of us say when we are not filling in cat show paperwork.

At the end of the day, your cat does not care what you call them, as long as dinner arrives on time and there is a warm spot on the sofa reserved in their honour.

Daphne certainly does not. She may be a grey cat on paper, but in spirit, she is one hundred percent blue-blooded royalty. And honestly? I would not have it any other way. 

See some more of my pet posts here! Interested in other kinds of cats? Read more about ginger cat personalities from first hand experience of owning one!

Becky

Meet the award-nominated UK lifestyle blogger behind Spirited Puddle Jumper – a mum of three living in South East London! Becky shares the real ups and downs of family life, parenting tips, and lifestyle inspiration, proving that being a mum doesn’t mean you stop being fun or having other interests! Follow along for honest insights into UK family life and opinions on a whole range of topics, from travel and food, to beauty reviews, home and DIY, business and health and wellness.