Breed · Dog

Cavalier King Charles Spaniel

Recreated in the 1920s from the toy spaniels of 17th-century portraits, and now one of the most popular small companion breeds.

It is hard to overstate how nice these dogs are. Affectionate without being demanding, good with everyone, small enough for a flat, happy with a modest walk. We would recommend the temperament to almost anybody. We cannot recommend the breed without you first reading the health section below, because the numbers there are not a footnote — they are the single most important fact about owning one.

At a glance

Lifespan: 9–14 years
Adult weight: 5.9–8.2 kg
Daily exercise: 30–60 min
Trainability: Good, eager to please
Alone time tolerated: Poorly — bred to be a companion
Shedding: Moderate
Noise level: Moderate
With children: Excellent
With other pets: Excellent

Colours · 4 listed

Four recognised colours, all long-established and all equally affected by the breed's health issues.

Blenheim
Tricolour
Black & tan
Ruby

Right for you if

You want a small, gentle dog for a household with children or older people.
Somebody is home most of the day — this breed does not cope alone.
A modest daily walk suits your life.
You will source from a breeder who follows the cardiac breeding protocol, and pay what that costs.

Wrong for you if

You cannot face the likelihood of serious cardiac disease in later life.
The house is empty all day. Separation distress is common and severe.
You are buying on price, or from anyone who has not health tested.
You want a dog you can leave outside. This is an indoor companion breed, full stop.

Health — the part that decides whether you should buy one

Mitral valve disease affects the great majority of Cavaliers, and far earlier than it affects other dogs: 97% of Cavaliers over three years old already show the valve prolapse that precedes it,¹ and 87% of three-year-olds with no murmur at all had it, against 7% of Beagles the same age.² The breed's susceptibility is heritable.³ This is not a rare risk to weigh — it is the expected course.
There is an established breeding protocol meant to push that onset later: breed no earlier than two and a half years, with clear hearts, from parents who were clear at five. Be clear-eyed about it — Sweden ran a national programme from 2001 and murmur prevalence in six-year-olds did not fall,⁴ and the UK scheme's 19-year results showed a gain in only one subgroup, with breeder compliance described as poor.⁵ That is the reason to ask, not a reason not to: the protocols are weakest where they are ignored. Ask the breeder whether they follow one, and which.
Syringomyelia, a painful condition caused by the skull shape, also runs in the breed.⁶ MRI screening exists. Ask.
If a breeder is offended by these questions, that is your answer. The responsible ones raise them before you do.

Sources

Pedersen HD, Lorentzen KA, Kristensen BO. Echocardiographic mitral valve prolapse in cavalier King Charles spaniels: epidemiology and prognostic significance for regurgitation. The Veterinary Record 1999; 144(12):315-20. Denmark doi:10.1136/vr.144.12.315 PMID 10212505 One hundred and fifty-three Cavaliers screened over a year: 82% of dogs aged one to three, and 97% of dogs over three, had some degree of mitral valve prolapse — the lesion that precedes regurgitation.
Pedersen HD, Kristensen BO, Lorentzen KA, Koch J, Jensen AL, Flagstad A. Mitral valve prolapse in 3-year-old healthy Cavalier King Charles Spaniels. An echocardiographic study. Canadian Journal of Veterinary Research 1995; 59(4):294-8. Denmark PMID 8548691 Blinded echocardiography: 87% of three-year-old Cavaliers with no heart murmur had mitral valve prolapse, against 7% of age-matched Beagles and none of fifteen Poodles.
Markby GR, Macrae VE, Corcoran BM, Summers KM. Comparative transcriptomic profiling of myxomatous mitral valve disease in the cavalier King Charles spaniel. BMC Veterinary Research 2020; 16(1):350. International doi:10.1186/s12917-020-02542-w PMID 32967675 Establishes that the Cavalier's susceptibility to mitral valve disease is heritable, with early onset. A study of valve tissue, so it carries none of the percentages quoted here.
Lundin T, Kvart C. Evaluation of the Swedish breeding program for cavalier King Charles spaniels. Acta Veterinaria Scandinavica 2010; 52(1):54. Sweden doi:10.1186/1751-0147-52-54 PMID 20863375 Sweden's Cavalier breeding programme began in 2001. Murmur prevalence in six-year-olds was 52% in 2007 and 55% in 2009 — no significant difference, and higher than earlier Swedish figures.
Swift S, Baldin A, Cripps P. Degenerative valvular disease in the Cavalier King Charles Spaniel: results of the UK breed scheme 1991-2010. Journal of Veterinary Internal Medicine 2017; 31(1):9-14. United Kingdom doi:10.1111/jvim.14619 PMID 28054393 The UK Cavalier breed scheme across 19 years and 8,860 dogs. Age at murmur detection rose only in bitches examined by general-practice vets, and breeder compliance with the voluntary scheme was poor.
Plessas IN, Rusbridge C, Driver CJ, et al. Long-term outcome of Cavalier King Charles spaniel dogs with clinical signs associated with Chiari-like malformation and syringomyelia. The Veterinary Record 2012; 171(20):501. United Kingdom doi:10.1136/vr.100449 PMID 23100307 Forty-eight Cavaliers with Chiari-like malformation and/or syringomyelia followed for 39 months. The condition is associated with neuropathic pain, and signs progressed in about three-quarters of them.

Every source here was checked, not recalled. Where this page makes a health statement and no source appears against it, that is not an oversight we have hidden — it means the claim is not yet sourced, and the build reports how many are in that state.

Availability, registration and keeping requirements differ from place to place. Check the rules where you live before you commit to any animal — we describe animals, not law.