Sealyham Terrier

Written by: Jamie
Updated: November 25, 2020

Interested in the Sealyham Terrier, a rare Welsh breed? Then take a look at the guide below for detailed breed information.

White Sealyham Terrier in the garden

Height: 10-11 inches
Weight: 8-9 kilos
Lifespan: 12-14 years
Pedigree? (registered with the KC?): Yes, this breed is registered with the Kennel Club.

Positives and Negatives

Check out the positive and negative features of the Sealyham Terrier below:


  • Hypoallergenic, ideal for allergy sufferers
  • Hardly sheds fur
  • Apartment friendly
  • Excellent watchdogs


  • Stubborn, not ideal for first-time owners
  • Potential to be dog aggressive if left unsocialized
  • Prone to weight gain
  • Likes to bark and dig


The Sealyham Terrier used to be one of the more popular breeds of the Terrier family. Today, they are listed as one of Britain’s most endangered native breeds. Bred to as ratters and hunters, Sealyham Terriers naturally hold a strong prey drive and won’t hesitate to start a chase.

This canine is less rowdy than others in the Terrier family, but they are still rather headstrong. A firm and consistent leader will be needed for the Sealyham dog. Their stubborn side makes them less than ideal for first-time owners. Training and socialization need to begin as early as possible, if not they could become dog aggressive.

Sealyham Terrier Dog standing on Lawn

Sealyham Terriers make excellent watchdogs and will always be on the alert. They hold a powerful bark that may need to be curbed so it doesn’t become continuous! Naturally, these Terriers like to dig so training will be needed to stop them from ruining any flower beds!

These pooches hardly shed their fur but will need lots of brushing in order to remove any loose strands. At least there will be no worries over the house being covered in fur! This trait is what makes them hypoallergenic, an ideal for those who suffer from allergies.

Weight gain can lead to obesity which could cause serious health issues. Sealyham Terriers are prone to weight gain so keep an eye on their calorie intake. This can be difficult during training when food rewards are offered. Opt for healthier food treats and keep track of how many are given each day. Reduce meal intake if necessary.


Sealyham Terriers originated from the Sealy Ham Estate by the Seal River in Southern Wales, during the 19th century. They were first bred by Captain John Edwards and were trained to hunt otters, badgers, foxes, and other game. This breed would often work in packs alongside the Otterhound, a large breed hunter.

Records of the Sealyham Terrier’s creation haven’t been kept. It is thought the West Highland Terrier, Dandie Dinmonts, Fox Terriers, white Bull Terriers, Welsh Corgis, and the now extinct Cheshire Terrier could be involved. Yet this can’t officially be confirmed.

It wasn’t uncommon for these dogs to have their tail docked, in fact, it was traditional practice. It would typically be docked to medium length because it was the easiest way to pull them out of rabbit holes. This, however, was completely stopped in 2007 after the Mutilations Regulations came into effect.

The Kennel Club recognized this breed back in 1910, just two years after the creation of the Sealyham Terrier Club. They were then registered with the American Kennel Club in 1911. It was during this time their popularity began to surge. Sealyham Terriers were so loved they won 4 ‘Best in Show’ titles at the Westminster Dog Show.

Whilst these pooches are still somewhat popular as Show Dogs, they just haven’t been a great hit as a general companion. The Kennel Club has listed the Sealyham Terrier as a vulnerable native breed. In 1938 there were 1,038 registrations, fast forward to 2004 there were approximately 60 registrations per year with the Kennel Club!

Related: Get to know more about the German Wirehaired Pointer breed here in this guide.


Sealyham Terriers have a bubbly personality, these dogs won’t fail to bring a smile to your face! They’re curious, alert, friendly, affectionate, and independent, with the ability to adapt to a range of different living environments. These canines can live happily in an apartment, provided their exercise needs are met.

A high prey drive and a feisty attitude could land the Sealyham Terrier in trouble if they aren’t socialized correctly. Yet they are known to be much calmer than other Terrier breeds, so training won’t be as tough. These pooches are also highly independent and won’t mind being left alone.

Are Sealyham Terriers Good With Strangers?

Sealyham Terriers can be aloof and reserved with strangers. The breed makes a terrific watchdog, but this also means they will constantly be on the alert. Strangers will be viewed as suspicious at first, but given the right socialization, this canine should feel settled.

Cute sealyham terrier puppy is lying in the autumn foliage

Are Sealyham Terriers Good With Children?

Sealyham Terriers make a great companion for older children. Play can become a little rough or excitable so smaller children should avoid this. Keep play supervised and always teach children how to treat a dog before allowing interaction.

Are Sealyham Terriers Ok With Other Dogs?

Sealyham Terriers have the potential to be dog friendly, after all, they were bred to work in packs. However, if left unsocialized this breed could become aggressive towards dogs they don’t know.

Remember, this Terrier is fearless and won’t back down from a fight, even if it’s a large breed. It is the responsibility of the owner to socialize and keep the Sealyham Terrier leashed. They can live with cats provided introduction takes place early.


An hour of daily exercise should be given to the Sealyham Terrier. This can be split into multiple walks. Due to their strong prey drive, these dogs should be leashed unless in an enclosed space. Maintaining this breed’s exercise is especially important as they can gain weight quickly.

sealyham terrier dog standing on grass

Mental stimulation will also need to be factored into their exercise routine. A bored Sealyham Terrier will pick up destructive behaviours such as chewing, barking, and digging. Interactive games and activities that make the dog think, are all great ways to do this.

Recommended: Check out our guide on the Nova Scotia Duck Tolling Retriever here at Woof Bark Growl.


Check out the breed-related health conditions of the Sealyham Terrier below:

  • Retinal Dysplasia- The abnormal development of the retina will cause a blur or loss of vision.
  • Lens Luxation- Threads holding the lens of the eye in place weakens, causing a shift in position. Symptoms include pain and clouding of the cornea.
  • Glaucoma- An increase of pressure within the eye will cause pain, loss of vision, and redness. This health condition often follows on from Retinal Dysplasia.

Intelligence & Training

Sealyham Terriers have an average level of intelligence but can pick up on commands rather quickly. This Terriers headstrong nature can, however, cause issues when house training. An experienced owner is recommended to overcome this.

The breed doesn’t like being told off! They’ll become stubborn and will lose complete concentration if training methods are harsh. Like most Terriers, positive reinforcement will be needed to encourage these canines. Whilst they love attention, food mostly works best. But don’t forget, this breed gains weight quickly!

Be clear when giving out and rewarding commands. Terriers prefer short, fun training sessions. These hard-working dogs can be easily trained, if in the right hands. Begin these lessons from 10-12 weeks. Socialization should also be included at this time. The fearless Sealyham Terrier could become aggressive if they aren’t mixed with other dogs.

This trait could also see them take on some fights they may be too small to win! These dogs are very curious and love to explore. Exercise them first, give them some mental stimulation then start a 10-15 minute training session. It will help the Sealyham Terrier concentrate better.

Recommended: Find out if the Neopolitan Mastiff is ideal for first-time dog owners here in our guide.


Sealyham Terriers barely shed their fur. A feature that suits allergy sufferers very well! The lack of shedding will require their coat to be brushed multiple times a week. Removing the loose strands of fur prevents tangles and knots from forming.

Sealyham Terrier Dog standing on Grass

This breed will benefit from a professional groomer every once in a while. Their coat requires hand stripping which isn’t easy for every owner. It is coarse and waterproof requiring a bath every 2-3 months. They can be bathed before this if dirty, but shouldn’t be washed anymore than once a month as this could cause dry skin.

A stripping knife, wide-toothed combs, grooming rakes, and slicker brushes are all ideal to use on the Sealyham Terrier’s coat. The fur around the anus can be shaven with a size #10 blade to keep the area hygienic. The topcoat, back of the head, neck, and ears are often trimmed and hand stripped, especially for show dogs.

Check the ears once a week removing any debris and excess strands of fur. Trim their nails once every 3-4 weeks or possibly longer depending on growth. Don’t forget to brush their teeth! Ideally 3-4 times a week however, vets recommend daily brushing.

About the Author

Hi, I'm Jamie! I've always been around dogs and now writing about them is an absolute joy.
Read more about my story here.
Reach me at or connect with me on LinkedIn below.

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