Calmest Dog Breeds: By Size (UK Guide)

If you're after a laid-back companion, breeds like the Basset Hound, Great Dane, Cavalier King Charles Spaniel, and Bernese Mountain Dog are consistently rated among the calmest dog breeds — genuinely calm dogs that suit a quieter household. But before you pick a breed based on this list alone, there's something genuinely important worth knowing: breed is a much weaker predictor of individual temperament than most people assume. Below: the calmest breeds by size, a quick match by lifestyle (flats, families, first-time owners), what the genetics actually show, and practical questions to ask before you bring a "calm breed" home.

Written by Jamie Sinclair, who writes about canine health, nutrition, and everyday care for Doggy Dailies — focused on translating veterinary research and real ingredient science into practical, honest guidance UK dog owners can use.

Table of Contents

• Before You Choose: What the Science Actually Says
• Which Traits Are Actually Heritable — and Which Aren't
• Calmest Small Dog Breeds
• Calmest Medium Dog Breeds
• Calmest Large Dog Breeds
• Calmest Breeds by Lifestyle: Flats, Families, First-Time Owners
• Calm Isn't the Same as Healthy: The Flat-Faced Caveat
• Adopting an Adult Dog vs a Puppy
• Questions Worth Asking a Breeder or Rescue
• Beyond Breed: What Actually Shapes Calmness
• FAQ
• Sources

Before You Choose: What the Science Actually Says

A large 2022 genetics study published in Science, surveying over 18,000 dogs and genotyping more than 2,000, found that breed explains just 9% of behavioural variation between individual dogs. The researchers concluded that breed is generally a poor predictor of an individual dog's behaviour and shouldn't be relied on alone when choosing a pet. That doesn't mean breed tendencies are meaningless — some traits, like biddability (how readily a dog responds to human direction), are more heritable than others — but it does mean any "calm breed" on this list could still turn out to be a live wire, and vice versa. Individual temperament, training, and socialisation matter enormously.

Which Traits Are Actually Heritable — and Which Aren't

This is worth unpacking a little further, since the same study found something genuinely useful: not all behavioural traits are equally predictable from breed. Biddability — how readily a dog takes direction from a person — showed a real, if modest, breed-linked pattern, meaning breed ancestry can genuinely help predict how trainable a dog is likely to be, even in a mixed-breed dog with that ancestry a few generations back. But "agonistic threshold" — essentially how easily a dog is provoked or startled by something uncomfortable, frightening, or annoying — was almost useless to predict from breed alone. The researchers also identified 11 specific genetic locations linked to behaviour across the genome, underlining that temperament genetics in dogs is real but genuinely complex, not a simple one-gene-per-breed story.

The practical takeaway for anyone using a "calmest breeds" list like this one: a breed's general trainability (biddability) is a reasonably useful signal, but how easily an individual dog gets rattled by fireworks, visitors, or a busy street is much closer to a coin flip based on breed alone — which is exactly the trait most people actually mean when they say they want a "calm" dog.

Calmest Small Dog Breeds

• Cavalier King Charles Spaniel — gentle, affectionate lap dogs that adore people; prone to mitral valve disease, so regular vet checks matter
• Shih Tzu — friendly and calm with a lively streak; content with short walks and indoor play; needs daily coat brushing
• Pekingese — independent yet affectionate, with genuinely low energy levels; a good fit for a quieter household
• Bolognese — loving, low-shedding, and content with a relaxed, indoor lifestyle
• French Bulldog — playful but generally easygoing; flat-faced breeds can struggle with heat and breathing, so keep exercise gentle (see below)

Calmest Medium Dog Breeds

• Basset Hound — gentle, adaptable, and famously low-energy; their standout trait is a phenomenal nose, not athleticism
• English Bulldog — typically calm and low-energy, but sensitive to heat due to their brachycephalic (flat-faced) build; avoid overexertion
• Poodle (Standard/Miniature) — mellow and highly intelligent, happy to laze about but still benefits from daily mental stimulation
• English Cocker Spaniel — affectionate and eager to please, content curled up beside you despite a sporting-dog background
• Whippet — surprisingly chilled for a breed built for speed; happy to sprint occasionally then flop on the sofa for the rest of the day

Calmest Large Dog Breeds

• Great Dane — a gentle giant with a quiet, easygoing nature; needs space and regular walks despite the laid-back temperament
• Greyhound — often called "the world's fastest couch potato" — remarkably calm and well-mannered indoors, and thousands of retired racers need homes in the UK
• Bernese Mountain Dog — affectionate, easygoing, and deeply loyal to family; needs early socialisation given their size
• Saint Bernard — impressively calm for their size, good-humoured, and devoted, though they can be vocal when defending home and family
• Bullmastiff — quiet and watchful rather than reactive; naturally protective without being prone to excessive barking

Calmest Breeds by Lifestyle: Flats, Families, First-Time Owners

Calm Isn't the Same as Healthy: The Flat-Faced Caveat

Several of the calmest breeds — French Bulldogs, English Bulldogs, Pekingese, Shih Tzus — are brachycephalic (flat-faced). Part of why they seem so relaxed is that breathing hard is difficult for them, which is why UK vets and the Kennel Club now urge buyers to think carefully before choosing one, and to look for breeders using respiratory grading. A calm temperament is a real trait in these dogs, but it comes packaged with heat intolerance, snoring, and in many cases airway surgery. If you want calm without that, the sighthounds, Bassets and Cavaliers on this list are the healthier route — with the caveat that Cavaliers carry their own heart-disease burden, so ask about parents' heart screening.

Adopting an Adult Dog vs a Puppy

Given how weak breed alone is as a predictor, one genuinely practical option most "calmest breeds" articles skip: an adult rescue dog already has an observable, settled temperament, rather than the genetic lottery a puppy still represents. A rescue or shelter that's had time to assess a dog's real behaviour — not just its breed label — can often match you to a genuinely calm individual dog more reliably than picking a breed off a list and hoping for the best with an eight-week-old puppy. This is particularly worth considering for the breeds on this list, like Greyhounds, where large numbers of calm, already-adult dogs need homes.

Questions Worth Asking a Breeder or Rescue

• Can I meet both parents (for a puppy), or spend time with the dog in a few different settings (for an adult)?
• How does this individual dog react to sudden noise, new people, or being left alone briefly?
• For a breed-specific health issue (heart screening in Cavaliers, hip/elbow scores in larger breeds), can I see the paperwork?
• What's the dog's history with children, other pets, and previous homes, if known?
• For a brachycephalic breed, has the dog (or its parents) had a respiratory function grading assessment?

None of these questions guarantee a calm dog, but they tell you far more about the individual in front of you than the breed name on its own ever will.

Beyond Breed: What Actually Shapes Calmness

Given breed only explains a small fraction of individual temperament, these factors matter just as much, if not more:

• Early socialisation — calm, confident adult dogs are shaped significantly by positive exposure to people, places, and situations as puppies, particularly between 3 and 14 weeks; our guide to calming a new puppy explains why that window matters more than breed
• Consistent training — predictable routines and clear boundaries support a settled temperament regardless of breed
• Exercise and mental stimulation — an under-exercised dog of any breed is more likely to seem restless or reactive
• Being left alone gradually — even the calmest breeds can develop separation anxiety if alone-time isn't built up from the start
• Individual personality — just like people, every dog is genuinely different, even within the same litter

If your dog isn't naturally the calmest, that's not a lost cause — natural calming support alongside training and routine can help many dogs settle more easily, whatever their breed. Our calming treats guide goes through what the ingredients actually do.

FAQ

What is the calmest dog breed overall?
Breeds like the Basset Hound, Great Dane, Greyhound, and Cavalier King Charles Spaniel are consistently rated among the calmest, though individual temperament varies a great deal even within a breed.

Is breed a reliable way to predict how calm a dog will be?
Not entirely — a major 2022 genetics study found breed explains only about 9% of behavioural variation between individual dogs, meaning training, socialisation, and individual personality matter enormously too.

What's the calmest small dog breed for a flat?
Cavalier King Charles Spaniels, Shih Tzus, Bolognese and Pekingese are popular choices for smaller spaces thanks to their gentle, low-energy nature — and a retired Greyhound is surprisingly flat-friendly too.

What's the calmest dog breed for first-time owners?
Cavaliers, Greyhounds, Whippets and Poodles combine a calm temperament with manageable training and grooming needs.

Are large dog breeds ever calm?
Yes — many large breeds, including Great Danes, Greyhounds, and Bernese Mountain Dogs, are notably gentle and low-energy despite their size.

Can training make any dog calmer?
Yes — early socialisation, consistent routine, and adequate exercise all play a significant role in a dog's temperament, regardless of breed.

Which behavioural traits are most predictable from breed?
Biddability (how readily a dog responds to direction) shows a real, if modest, breed-linked pattern. How easily a dog is startled or provoked is far less predictable from breed alone.

Is an adult rescue dog a safer bet for calmness than a puppy?
In some ways, yes — an adult dog's temperament is already observable, whereas a puppy's adult temperament is still largely unknown regardless of its breed.

Sources

• Morrill et al. (2022) — Ancestry-inclusive dog genomics challenges popular breed stereotypes, Science
• Broad Institute — Dog genetics suggest that behavior is more than just breed

This article is for general information only. Every dog is an individual, and breed tendencies don't guarantee any particular dog's temperament.