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Bullmastiff: The Ultimate Guide

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Whoever said that size isn’t everything had obviously never met a Bullmastiff.

When you bump into one of these adorable couch potatoes who are thoroughly and totally devoted to their families, you can’t help being bowled over by their size, largely because they’ll barrel into you at a thousand miles per hour before smothering you in an endless barrage of sloppy, mastiff kisses. 


It’s impossible to ignore a Bullmastiff’s size, as they’re one of the biggest breeds of domestic dog in the world.

But don’t be intimidated by it, as these loyal and loving giants are really just big, soft cuddle monsters who would rather while away their days having their tummies scratched while cuddled up in front of the television than exploring the outside world.

If you’re looking for a four-legged friend and canine companion who enjoys all the comforts of home, and will always stand firm and protect his family from harm, then it’s time you met and found out everything that you’ll ever need to know about the Bullmastiff. 

Bullmastiff Key Facts

Before you dive any further into this guide to the loveable leviathan, there are some things that you’ll need to be immediately aware of.

Such as how long your boy will be part of your family for, how much exercise he’ll need to be happy and healthy, what his coat looks like, and, most importantly, how much it will end up costing you to keep him in the style that he’d like to become accustomed to.

So let’s not dilly dally any further, and let’s get stuck straight onto what you need to know. 

Average Lifespan: Bullmastiffs are big dogs and unfortunately big dogs don’t tend to live as long as their smaller cousins do.

Maybe the reason they don’t live as long as they should is  that they have so much more love to give and that their hearts don’t last as long as small dogs can, but whatever the reason is,  big dogs don’t get to spend as long with their families as they, and their loved ones would like.

And being one of the biggest dogs in the yard, Bullmastiffs have an average lifespan of just eight to ten years. 

Minimum Exercise (per day): They may be big, but that doesn’t mean that they need a lot of exercise.

Most Bullmastiffs don’t need more than a few short to medium length walks a day, and will be happy to go out for a potter and stroll once in the morning and once in the evening. 

Coat Length: They’re a short-haired breed, so their coats will never be excessively long, making them easy to groom and means that you won’t end up wading through mountains of excess, shed hair. 

Minimum Cost Per Month: When you factor in all the costs and add up all of the things that your Bullmastiff is going to need such as food (and being BIG dogs, they’ll need a lot of food) and pet insurance, the minimum cost of keeping a Bullmastiff is roughly one hundred and fifty to two hundred dollars a month. 


Bullmastiffs are larger than large dogs that are built like they’ve spent a lifetime working out at the local gym. They’re a short-muzzled breed that looks imposing until you catch the infinitely curious expression on their faces that belies their true nature.

Their short fur is either brindle, reddish-brown, or light tan, and as soon as they know, or are familiar with, you, they’ll invite you to stroke it all day and every day. 

Size: Males tend to be slightly bigger than females, and the breed is classified as being a large dog by the American Kennel Club.

Which means, as we’ve already mentioned a couple of times, that they’re big. And you’ll also need to be aware of the fact that Bullmastiffs don’t actually stop growing, and won’t reach their full adult height and weight until they’re two years old. 

Average Height: According to the American Kennel Club guidelines, males should be between twenty-five to twenty-seven inches tall at the shoulder and females should be between twenty-four and twenty-six inches tall at the shoulder. 

Average Weight: The average Bullmastiff, regardless of whether it’s a male or female dog, should weigh between one hundred and one hundred and twenty pounds. Any heavier dog is considered overweight, and any less and the dog needs to bulk up. 


Bullmastiffs are playful, affectionate, and loyal dogs. However, they tend to be overly protective and don’t always greet new people with the same cheery disposition they reserve for their nearest and dearest.

Bred to be watch and guard dogs, they tend to form close bonds with the people they know and can be aggressive toward other dogs. 

Apartment Living: Bullmastiffs take to apartment life like a fish to water. As they’re easy-going, relaxed dogs who adore the couch and lazing around, they’re happy to be wherever you are.

The one big problem, and it is a big problem, is their size. Bullmastiffs are big dogs, so they’re not ideally suited to living in a small apartment. 

Good For Novice Owners: They’re not a great dog for first-time owners, as they’re incredibly strong and can be stubborn.

They need to be trained and socialized from an early age, and as such aren’t the best dogs for anyone who hasn’t been down that path before and already knows what it entails. 

Sensitivity Level: Bullmastiffs are big dogs with a heart of gold and are incredibly sensitive and emotional. It’s one of the facets of the breed that makes them such good family dogs, as they want to be loved and they have a lot of love to give in return. 

Tolerates Being Alone: As a breed, they’re not prone to separation anxiety, and providing that they have enough toys to make sure that they don’t get bored when they’re left by themselves, they shouldn’t be destructive either.

If they get enough exercise, they’re fine to be left on their own during the day while you go to work.

Tolerates Cold Weather: Bullmastiffs are generally fine in cold weather and cope well with it as long as the temperature doesn’t plummet past freezing and keep on going down and down. You’ll need to consider getting your best boy a coat if it does. 

Tolerates Hot Weather: They don’t cope well with excessively hot weather and are prone to heatstroke and breathing difficulties when it gets too hot. If it gets too hot outside, you’ll need to keep your Bullmastiff inside with the air conditioning turned all the way up. 

Affectionate With Family: Bullmastiffs are incredibly loyal, loving, and affectionate dogs and love nothing more than spending time hanging out, and cuddled up, with their families.

They also fiercely protect their families and will do anything to ensure no harm befalls them. 

Kid-Friendly: Bullmastiffs are tolerant, patient, and wonderful with children if they know them, so if you’re going to bring a Bullmastiff into your home, you have nothing to fear as they will never hurt the smaller member of their “pack”.

However, as young Bullmastiffs can be boisterous, they can easily bowl small children over, so they might not be an ideal choice of family dog if your kids are aged five or under. 

Dog Friendly: They can be aggressive toward other dogs, so it’s always a good idea to socialize Bullmastiff puppies at a very early age to help to curb this behavior.

A well-trained and socialized mastiff can be an absolute joy, but one that hasn’t been taught to behave properly can be difficult to control around dogs that he, or she, doesn’t know. 

Friendly Toward Strangers: The breed can be standoffish toward strangers, and every new human is a stranger to a Bullmastiff until they’ve been properly introduced to them by their family. 

Health & Grooming


Even though they’re big, bouncy, energetic dogs, like every other breed, there is an inherent number of health problems that Bullmastiffs are susceptible to, which we’ll detail a little further on.

But just because the breed as a whole is vulnerable to these health problems and issues, it doesn’t mean that your Bullmastiff will suffer from, or fall victim to, any of them. 

Shedding: They’re a short-haired breed, so they don’t shed a lot and only tend to shed during the Summer and Spring when they’re getting ready for the warmer weather to arrive. 

Drooling: Bullmastiffs drool a lot; when we say a lot, we mean they droll rivers and lakes.

They drool when they’re happy, hungry, and in their sleep. And that’s a lot of drool, so if you’re not exactly keen on dog slobber, they might be the dog that you’ve been looking for. 

Grooming: Being short-haired dogs Bullmastiffs are easy to groom. All you need is a dog brush and a couple of minutes a day to keep your boy’s coat shiny, well-groomed, and healthy.

General Health: While they tend, if they don’t suffer from any of the breed-specific ailments, to be fairly robust dogs, Bullmastiffs can be quite flatulent, so it’s important to monitor what they eat and which foods tend to make them gassier than others do, and if possible eliminate the gas-happy items from their diets. 

Their short muzzles and noses mean that they’re also a brachycephalic breed, and can have breathing problems during hot weather or if they push themselves too hard while they’re out and about and having fun, which is an issue that every potential owner needs to pay close attention to. 

Bullmastiffs also have sensitive skin, which can lead to them developing dermatitis and other associated skin issues, which can be prevented by a careful grooming regime. It doesn’t always work, but it’s more successful than not. 

Common Health Problems: As we mentioned earlier, Bullmastiffs are prone to a number of different health conditions which include hip and elbow dysplasia (painful joint problems that can lead to arthritis), hyperthyroidism, entropion (where the eyelid folds over onto the eye, which needs to be surgically corrected to prevent the dog from eventually going blind), Subaortic stenosis (a genetic cardiac condition which manifests as a lifelong heart problem), gastric and digestive issues, and a disease that the breed is particularly sensitive to, cancer. 

Potential For Weight Gain: Due to their easy-going, almost lazy nature and love of food, the Bullmastiff is a little more inclined than a lot of other breeds to pile on the pounds. Their weight and diets need to be carefully monitored to stop them from getting fat. 

Bullmastiff Trainability

Every Bullmastiff needs to be trained and socialized from an early age in order to combat their potential aggression toward other dogs, and so that they’ll understand from the beginning who is really in charge in your household. 

Easy To Train: Because they’re strong, stubborn, and independent dogs, Bullmastiffs need to be trained from an early age.

The older and more self-assured they become, the harder they are to train. But as long as they’re trained and socialized as puppies, they’re not particularly difficult to train. 

Intelligence: Bullmastiffs are intelligent, bright dogs and can master new skills relatively quickly. It’s the main reason why they’re also easy to train because it’s started early enough.  

Potential To Bite: Even though the breed can be aggressive toward strangers and individuals that they regard as a potential threat, they will only bite as a last resort. they’ll bark, growl and threaten for a long time before they even think about using their teeth. 

Tendency To Bark Or Howl: Bullmastiffs aren’t vocal dogs and don’t tend to bark or growl a lot unless they think that it’s absolutely necessary. Most of the time, they’re a perfectly quiet family pet. 


The long and storied Bullmastiff line began in the nineteenth century when English gamekeepers bred bulldogs with mastiffs in an attempt to create a dog that would help them to effectively deal with poachers.

And because the resultant dog was so good at what it was bred to do, it earned the nicknames ‘the silent guardian’ and the “gamekeeper’s night dog”, and while the former is still used to describe Bullmastiffs, the latter has almost been forgotten by history. 

The English Kennel Club didn’t recognize the breed until nineteen twenty-four and the American Kennel Club followed suit a decade later.

During the late nineteen twenties, De Beers began to favor using Bullmastiff to guard their diamond mines in South Africa, which led to the breed establishing itself in the country. 


Bullmastiff puppies can be incredibly expensive, and the cost is dependent on their family line, and the breeder selling them. They tend to vary in price but are usually between fifteen hundred and thirty-five hundred dollars.

And over the course of their relatively short lives, in order to properly care for a Bullmastiff, the American Kennel Club estimates that it would cost the average owner somewhere in the region of nineteen thousand dollars. 

However, even though the puppies cost a lot of money, it isn’t uncommon to find Bullmastiffs in shelters. 

And the reason for this is both simple, and heartbreaking. The dog is usually abandoned because the owner was inadequately prepared to care for it properly, and didn’t understand the enormity of the task that they were undertaking. 

Bullmastiffs demand a great degree of care and need a great deal of attention.

They need to be trained and socialized and made to feel like they’re an important part of everyday family life, which is why so many of them tend to end up in shelters or with specialist rehoming programs. 

If you do want to give a Bullmastiff a home before you start shopping around and looking for breeders, think about adopting instead.

Phone your local shelter and leave your number, or get in touch with a Bullmastiff rescue center near you and ask them about rehoming one of the dogs in their care. 

It’ll cost you far less than it would to buy a Bullmastiff from a breeder, and you’ll be giving a home to a dog that desperately needs, and wants one. 

Bullmastiff Fun Facts 

The NFL team the Cleveland Browns who are, funnily enough, based in Cleveland, Ohio have a living mascot. His name is Swagger, and he’s a Bullmastiff. 

The most famous boxer in cinematic history, Rocky Balboa had a pet dog called Butkus, and Butkus was, as you’ve probably already guessed, a Bullmastiff.  

They were originally trained to do things a little differently, and rather than bark at, or bite poachers, Bullmastiffs were taught to pounce on them and pin them to the ground until their masters arrived. 

The first Bullmastiffs were imported to America from England by John D Rockefeller during the nineteen twenties to guard his estate and properties in New York.

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About the author


Kerry White is an avid dog lover and writer, knowing all there is to know about our furry friends. Kerry has been writing for PetDT for three years now, wanting to use her knowledge for good and share everything she can with new dog owners.Kerry has two dogs herself - a German shepherd called Banjo and a chocolate labrador called Buttons. Kerry knows more than anyone how adjusting to new life with a puppy can turn your life upside down, and she wants to ease some of the burdens through her articles.