Grey Cat Breeds: Russian Blue, British Blue & More

Why are grey cats called blue?

Blue is the cat-fancy name for grey, and genetically a blue cat is a diluted black cat. A 2006 study by Ishida and colleagues describes the dilute phenotype in domestic cats: “black pigmentation combined with dilute appears gray and orange pigments appear cream.” They traced it to a single-letter deletion in a gene called MLPH (melanophilin), one of the proteins that spreads pigment granules evenly. The deletion cuts the protein short, and the coat looks paler.

• It is recessive. A cat must inherit the variant from both parents to be blue, so two black cats that each carry one copy can have blue kittens, and two blue cats have only dilute kittens.
• It is the same gene in every breed. The study found the same variant in 97 unrelated dilute cats from 26 breeds and random-bred cats, and concluded a single mutation event gave rise to dilute in domestic cats. A Russian Blue and a grey moggy are grey for the same reason.
• It affects other colours too. Dilution turns ginger to cream and black-and-orange tortoiseshell to blue-cream. Our moggy colours guide covers those.

What separates the grey breeds is everything else: coat length and texture, silver tipping on the hairs, body shape and, most usefully, eye colour.

Which cat breeds are grey, and how do you tell them apart?

Sources: CCCA Russian, Korat and British Shorthair standards; ACF Russian, Korat and Nebelung standards; CFA Chartreux. Recognition from the CCCA and ACF standards lists and the ANCATS breed list, all read 10 November 2026. Councils add breeds over time; ask a breeder which council registers their cats.

The quick test is the eyes. Green means Russian, Korat or Nebelung. Gold, orange or copper means British Shorthair or Chartreux. Then look at the coat: a long coat is a Nebelung; a single, close-lying coat with obvious silver tips is a Korat; a plush coat that stands out from the body is a Russian.

Russian Blue

The best-known grey breed, called simply the Russian in the Australian standards. The CCCA standard describes a double coat with “a distinct silvery sheen or shimmer in all colours,” and calls that coat the breed's most important characteristic. Its blue is “clear, light to medium,” free from tabby markings in maturity, and the eyes are “clear, vivid green,” with allowance in kittens whose eye colour has not fully developed. The CCCA and the ACF both also accept Russian White and Russian Black, and ANCATS says that originally the Russian cats were blue cats.

Pedigree Russians are uncommon in rescue. Our Russian Blue adopt-or-buy guide covers registered breeders (the Russian Cat Council of Australia lists them), prices, the allergy myth and the look-alikes.

British Shorthair (the British Blue)

The British Shorthair comes in many colours, and blue is the colour behind its nickname: the CFA says these cats were first registered in the United States as “British Blues.” The CCCA standard (December 2024) asks for a light to medium blue, sound to the roots, with darker tones undesirable, and says “silver tipping is a fault,” the opposite of the Russian and Korat. Eyes range from deep gold through orange to copper, with no trace of green. The CCCA describes a solid, powerful cat with a short, level back and short, strong legs, with no tendency to fine legs.

For breeder checks, HCM heart testing and British Blue crosses in rescue, see our British Shorthair adopt-or-buy guide.

Korat

A Thai breed that comes in one colour only. The ACF standard calls it “a rare cat even in Thailand,” regarded there as a “good luck” cat, and describes a silver-tipped blue coat where the hair is lighter at the roots and deepest blue just before the silver tips. The CCCA standard says “the more silver the better” and penalises lack of silver tipping; the CFA disqualifies “any color but silver-tipped blue.”

The eyes are large and prominent, “luminous brilliant green, but amber cast acceptable.” Kittens and adolescents have yellow or amber-green eyes, and the CCCA says full eye colour may not be established until maturity, which can take up to three years. LocalPetFinder has no Korat breed page; a green-eyed grey cat in rescue is far more likely to be a moggy, as explained below.

Chartreux

A French breed with a woolly blue coat and orange eyes. The CFA standard allows “any shade of blue-gray from ash to slate; tips lightly brushed with silver,” with eyes from copper to gold and “a clear, deep, brilliant orange” preferred; green eyes disqualify. The CFA says the coat is dense, woolly and somewhat water-resistant, and that the old story of the Carthusian monks is uncertain: the name may come from a type of Spanish wool instead.

Recognition in Australia is patchy. The Chartreux has no standard on the CCCA or ACF standards lists we read in November 2026. ANCATS includes it in the breed list on its website. Internationally, FIFe names it among the breeds it has recognised since its foundation in 1949. If you are offered a Chartreux kitten here, ask which council registered the litter and check the membership yourself.

Nebelung

A semi-longhaired blue cat with green eyes. The ACF standard (effective 1 January 2020) describes “an elegant cat of foreign type with a semi-longhair coat of soft, silky texture in an attractive, medium blue with a silvery sheen,” asks for “an even, clear, medium blue” with silver-tipped guard hairs, solid pattern only, and green eyes “as vivid as possible.” Its only allowable outcross is the Russian Blue, which is why it is often called a long-haired Russian. The standard also notes Nebelungs are shy and need quiet, gentle handling.

In Australia, the Nebelung has a standard with the ACF but is not on the CCCA standards list or the ANCATS breed list we read.

Which other breeds come in blue?

Many. Because dilute is one widespread recessive gene, plenty of breeds list blue among their colours: the CCCA Burmese standard, for example, recognises blue and blue tortoiseshell, and the Ragdoll has blue points. What makes the five breeds above “grey breeds” is that blue is their signature colour, or their only one.

Is my grey rescue cat a pedigree?

Almost certainly not, and that is fine. In a University of Sydney study, Miller, Ward and Beatty (2019) analysed 2,584 cats adopted from a metropolitan Sydney shelter: 99.1% were mixed breed, and 142 (5.5%) were grey, a category the authors defined to include grey, charcoal, silver and blue. So a grey cat in rescue is usually a blue Domestic Shorthair or Domestic Longhair: a moggy with two copies of the dilute gene. Shelters sometimes describe a grey cat as a Russian Blue or British Blue by its look; without papers, that is a description, not a pedigree.

The same study is good news for grey cats: compared with black cats, grey cats did not stay significantly longer before adoption; only white cats did. Our Domestic Shorthair guide explains the moggy label.

Does a grey coat mean anything for health, allergies or personality?

• Allergies: no. ASCIA says all cat breeds can cause allergies, because all cats have sebaceous glands. A grey coat, and a Russian Blue's reputation, do not change that. See our hypoallergenic cats guide.
• Health: no colour link we found. Dilution is a pigment change. Breed health points belong to the breed: the British Shorthair, for example, is among the breeds believed to be at increased risk of HCM heart disease, as our British Shorthair guide explains.
• Personality: breed and individual, not colour. We found no study linking grey or blue to behaviour in cats. Breed descriptions differ (the ACF calls the Nebelung shy), but every cat is an individual; ask the rescue or foster carer.

How do you adopt a grey cat?

Through rescue, like any cat. Fees go by age and rescue, not colour. RSPCA NSW lists $220 for a cat over six months and $270 for a kitten, and the Cat Protection Society of NSW lists $150 per cat or kitten, or $250 for two (both checked 10 November 2026). These are reference figures, not quotes; check the rescue's own page.

If you want a papered Russian, British Shorthair or Korat, a registered breeder is a reasonable choice; check the council membership yourself, as our adopt-or-buy guides explain. For the wider decisions, see adopting a cat in Australia, types of cats and the what cat breed am I quiz.

Find a grey cat near you

• Sydney: grey cats, Russian Blues, British Shorthairs, kittens
• Melbourne: grey cats, Russian Blues, British Shorthairs, kittens
• Brisbane: grey cats, Russian Blues, British Shorthairs, kittens
• Perth: grey cats, Russian Blues, British Shorthairs, kittens
• Adelaide: grey cats, Russian Blues, British Shorthairs, kittens
• Australia-wide: all grey cats, Russian Blues and British Shorthairs. City guides: Russian Blue adoption in Sydney, British Shorthair adoption in Melbourne.

Not sure yet? The adoption readiness check takes five minutes, and the dog or cat? quiz helps if you are still deciding on the species.