Bullmastiff – The Ultimate Guide to Bulldog and Mastiff Crossbreed

Written by: Kristina Lalovic
Bullmastiff is a strong, independent breed that makes a great guard dog. But, that shouldn't come as a surprise considering that one of this dog's breed parents is a powerful Mastiff. Discover everything there's to know about this crossbreed of Bulldogs and Mastiffs and read on!
Dog Breed Group:
Working Dogs
24 to 27 inches at the shoulder
100 to 130 pounds
Life Span:
8 to 10 years

Breed Characteristics:

Apartment Friendly


How well will this breed adapt to apartment living? Is the apartment size the most important factor when it comes to proper living conditions? Is the breed suitable for apartment living?

Good For First-Time Owners


Some dogs aren't suitable for first-time dog owners. Is this breed a good match for someone with no dog experience? Can training help them be on their best behavior with owners with no dog experience? Are they suitable to be handled by someone who is just entering the canine world?

Overall Sensitivity


Some dogs are sensitive. Certain breeds are rough on the outside, while having the softest heart on the inside. In other words, some dogs are 'thick-skinned' while some are 'easygoing.' Is this breed prone to sensitivity?

Tolerates Being Alone


Separation anxiety in dogs is a serious condition that can affect a dog's life quality. Is this breed prone to this condition? Can you leave him alone for hours? How destructive this breed can become when bored, neglected, or not loved enough?

Affectionate With Family


How affectionate this breed will be around his humans? Will he welcome new family friends easily or he will choose to be shy? Some breeds can be clingy with owners, while others don't attach a lot. Will this breed act as the family's best friend?



Some dogs will tolerate children, while others will adore well-behaved ones. Dogs and children should always be supervised, no matter how well trained the dog might be. Will this breed act as a nanny dog or he will stay away from children?

Friendly Toward Other Dogs


Some dog breeds cannot wait to run to the dog park and run with others. Others prefer to be with their humans, and not to be a part of a multi-pet household. Is this breed dog lover or not? How friendly this breed will be toward other dogs?

Friendly Toward Strangers


Some dog breeds tend to be reserved toward strangers and highly suspicious. Others are fast to walk away with them easily. How welcoming this breed is toward strangers?

Drooling Level


If you love to clean all the time drooling level in dogs is a trait that you should mind. Is this breed less likely to drool, or you will always need a towel on hand?

Easy To Groom


Heavier shedding during the shedding season is something that every dog needs to go through. However, some dogs shed just a bit all year round. Is this breed one of them? How often should you groom this dog?

Overall Health


What can you expect from this breed in terms of health? Are there any genetic conditions to vary about? Is obesity a major issue in this breed? By knowing more about the dog's health, you are learning how to help him live a longer and healthier life.

Prone To Obesity


Treats are a great addition to training sessions. Dogs love sweet bites of dog treats but they should be served in moderation. Treats can lead to obesity, next to poor nutrition. Can this breed gain extra weight from treats? How prone to obesity this breed actually is?

Trainability Level


Training some dogs is easier than others. How easy this dog will be to train? What can you expect? Some dogs are huge people pleasers and they will master commands easily, while others will try to outsmart you.

Intelligence Level


Dogs are smart beings. We do our best to train them, but they do still end up training us to adapt to their needs. How intelligent is this breed? Will he try to outsmart you? Or he will need multiple training sessions to master basic commands?

Prey Drive


Dogs were bred for a specific purpose. Those who were bred to hunt have natural instincts to hunt, even today. This is why many dogs, like Terriers, will chase other animals. They will also have a hard time concentrating on your commands when there is something small moving. Is this breed prone to following his prey instincts?

Barking Level


How vocal this breed is? Can you expect neighbors to ring you often to calm your dog? Or you can sleep without worries of hearing your Fido bark? Some breeds are highly vocal, others have unusual sounds, and some are silent. Is this breed prone to barking?

Energy Level


Low-energy dogs are happy with regular walks and indoor chill times. High-energy dogs are always ready for action. Is this breed a couch potato, energetic dog, or somewhere in between?

Exercise Needs


Some dogs are more than happy with a slow stroll down the street. Others need hours of active time to stay happy and fit. Is this breed demanding in terms of exercise? How much exercise this breed needs to stay happy and healthy?

Playfulness Level


Some dogs never lose that puppy spirit, not even in their senior years. Others are more serious and prefer having a job to do. Is this breed demanding in terms of playfulness? Can you expect playfulness in their senior years as well?

A Bullmastiff is a dog of a strong, fearless stature and some really powerful heritage. He is the most affectionate pet with his loved ones, but can be quite aloof and suspicious toward strangers and unknown people.

Learn more about this great bread and discover if a Bullmastiff is the right dog for you!

Quick Facts

Real name: Bullmastiff
Origin: U.K.
Breed type: Crossbreed
Weight: Male: 50–59 kg (110-130 lbs), Female: 45–54 kg (99-119 lbs)
Height: Male: 64–68 cm (25-26 in), Female: 61–66 cm (24-25 in)
Color: Brindle, Brown, Fawn, Red
Coat: Short coat
Lifespan: 8-10 years

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The Bullmastiff was bred during the mid-1800s in England for a specific role – gamekeepers’ companion dog.

The gamekeepers of England wanted to create a dog breed that could help them in tracking down the poachers. They experimented with different breeds and tried to obtain the right kind of a dog for them. Eventually, they realized that what they needed was a dog quicker and more aggressive than a Mastiff, but less ferocious than a Bulldog. Bulldogs of 19th and the beginning of 20th century weren’t the same docile bulldogs we know today.

However, why did they need a dog of these traits?

Namely, in the mid-19th century, poaching was a hanging offense and English gamekeepers had a dangerous job of catching armed poachers. Eventually, they realized how to make their job much easier! They bred a large, quiet, but fearless dog that was fast enough to track down the poachers, and strong enough to hold them on the ground. Also, the breed’s common brindle coat provided natural camouflages needed for the job.

Since the Bullmastiff met all the requirements the gamekeepers wanted, it got nicknamed as the Gamekeeper’s Night-Dog.

But, when poaching declined, the need for Bullmastiffs to track poachers declined too, and they gained a new role: the one of a guardian dog. In fact, they were used in South Africa to guard De Beers diamond mines.

However, modern bullmastiffs are rather friendly, easygoing companions than fearless guardian dogs.

Breed Origins

Let’s outline a few interesting things about Bullmastiff’s parent breeds: The Bulldog and The Mastiff.

The Bulldog is a dog of a bloody past: to drive cattle to market and to compete in bullbaiting. They were bred to be aggressive which is why the Gamekeepers chose exactly this breed. However today’s bulldogs are gentle pets that adore spending time with kids. They will enjoy a short walk, but will also indulge in napping on the sofa. Bullmastiffs English parent has passed him a short-muzzled head and short coat.

The Mastiff, on the other hand, is one of the most ancient dog breeds out there. He is an ancestor of the molossus, the ancient dog that existed 5,000 years ago. Mastiffs also used to have a ferocious history, as they were used as war dogs. Today’s mastiffs are still fierce, but have a much more docile personality. Being the largest dog breed of all, Mastiffs will be great guard dogs, which is a trait they passed onto Bullmastiffs too.

Physical Appearance

The Bullmastiff has a broad, wrinkled head and a short, black muzzle. His ears are V-shaped and his eyes are often dark hazel. A Bullmastiff’s tail is set high on the rear.

Bullmastiffs are large dogs of a powerful body and heavy bones. However, they are not as big as their breed parent Mastiff that is considered as the largest dog of all breeds.

Bullmastiffs will easily reach the height of 27 inches and can weigh between 100 to 130 pounds. So, if you plan on getting one, make sure you have plenty of space for this dog.

These dogs are short-coated and usually come in fawn, red or brindle colors. This is a common trait seen in Pit bulls as well, which is why Bullmastiff is commonly mistaken for this short-coated breed.

Did you know that due to its square-like thread this breed is always compared to Boxer, making it one of the largest dogs that look like Boxers


Don’t let their poacher-tracking past fool you. The Bullmastiffs are incredibly intelligent and can make wonderful family dogs. They are loyal, calm, and quite easygoing when properly trained and socialized.

Bullmastiffs will be most gentle and affectionate dogs towards all family members if the socialization and training is done quite early in their lives. They can also do well with well-behaved children. However, their laid-back attitude with people from the family can easily change when someone unknown to them approaches the house.

They will likely be suspicious towards strangers and people outside the family. At times, his protective genes can also make him aggressive towards people he doesn’t know. If there are other dogs at home, a Bullmastiff will likely be less tolerant towards them than of his human family members.

Grooming (Shedding)

Bullmastiffs have a short coat that doesn’t require a lot of grooming. Also, an average, healthy bullmastiff is a low-shedder that will however shed much more during seasonal shedding.

As long as you provide him with occasional grooming and bathing, your bullmastiff should be more than fine with it.

Regular walking should also work to trim down his nails. But, if the activities your bullmastiff has don’t wear down its nails, make sure to trim them every now and then (if you hear the nails clicking on the floor- it’s usually a sign that it’s the right time to trim the nails!).

While coat grooming and nail trimming won’t take too much of your time, there’s something else you should be taking care of when it comes to owning a Bullmastiff. Its facial skin folds should be kept clean and dry, so make sure you clear any traces of dirt, food or water on your Bullmastiff.

Since Bullmastiffs drool a lot, you might also have a bib or a cloth by your hand that you would use to clean your dog up.


Bullmastiffs are known to be dogs of quite an independent personality. While this might have some pros when it comes to their temperament, it can also bring some cons, especially when it comes to training. Usually, independence in temperament equals stubbornness in training. And this is also true for bullmastiffs. They are strong willed creatures that need a strong individual to guide them.

Make sure you have a firm, fair and consistent approach in training since the early days, and your Bullmastiff should accept to obey your commands. You have to make him realize who’s the master of the household from an early age, or your Bullmastiff will be running things his own way.

Once he accepts that you’re the boss, you will be able to maintain and enrich your special bond with your Bullmastiff.

Due to his guardian instincts, early socialization is crucial for these dogs. Make sure you expose your Bullmastiff puppy to different people, sights, sounds, and places, so that he doesn’t have unwanted, unpredictable reactions in future.


Bullmastiffs are low-energy dogs that adapt well to apartment living. However, some dogs of this breed can be moderately active while others would prefer a sedentary lifestyle. In any case, daily exercise will be enjoyed by every single dog, and so it will be for a Bullmastiff too. In order to keep him fit and healthy, make sure he has a good exercise routine.

Anyway, a bullmastiff won’t require too much exercises, in fact, excessive workouts, especially during hot days, should be avoided. Their short muzzle makes them more prone to heat exhaustion and heatstroke. If your bullmastiff loves to stay in the yard often, make sure to provide him with shade and fresh water.

Also, walking him without a leash probably wouldn’t be the best idea, as they don’t do well with other dogs.

Health And Longevity

Bullmastiffs have proved to be a generally healthy breed. But, when it comes to crossbreeds, litter’s health depends mostly on the choices of breeders. When choosing a Bullmastiff, make sure you do your research and look for responsible breeders that meet the highest breed standards established by relevant kennel clubs.

If find a good breeder that you can trust, your Bullmastiff should be a healthy, happy puppy just like any other. The lifespan of a healthy Bullmastiff is usually of 8 to 10 years.

However, some hereditary health problems can still occur, which is why it’s crucial to have occasional health tests of:

  • Hip Evaluation
  • Elbow Evaluation
  • Ophthalmologist Evaluation
  • Cardiac Exam
  • Thyroid Evaluation

Due to it’s short muzzle, bullmastiffs can be prone to overheating. Therefore keep your dog cool in hot weather and never force him to excessive exercise.

Check out this infographic we made on Bullmastiffs! Let us know what you think about it!

bullmastiff infographic

Frequently Asked Questions

Are Bullmastiff Dogs Dangerous?

Bullmastiffs aren’t dangerous dogs if they are properly trained in early age. Although they will have a somewhat suspicious approach to strangers, they shouldn’t attack anyone if not trained to do so. Being so protective of their territory, it’s advisable to ensure a Bullmastiff with a fenced, safely contained area to which unfamiliar people or animals wouldn’t be able to enter easily.

Do Bullmastiffs Shed A Lot?

Bullmastiffs are not big shedders, but they will likely shed more on seasonal changes. Their coat is short and very easy to maintain. However, it’s not their fur that makes them a bit messy, but it is their drooling.

You should get a Bullmastiff if you’re looking for a dog that is:

  • Large sized
  • A good guardian
  • Not overly active
  • Easygoing and affectionate towards his family members
  • Doesn’t shed much
  • Doesn’t need too much exercise

On the other hand, a Bullmastiff might not be the right dog for you if you don’t want these traits in your dog:

  • Suspicious towards strangers
  • Drools a lot
  • Doesn’t enjoy being alone
  • Doesn’t do well with other dogs

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