How long do Mastiffs live?


How long do Mastiffs live?

Mastiffs are beautiful and loyal companions as well as excellent watch and guard dogs. Many families decide on a Mastiff puppy due to the size and temperament of the breed. But how long do Mastiffs live? What is a typical lifespan?

Generally speaking, most Mastiffs live to be 6-12 years. This is quite a big time span – which age your Mastiff specifically will reach will depend on a number of factors. Below we will look at the most important ones.

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How long will my Mastiff live?

Unless your Mastiff suffers an unfortunate accident or injury, he will most likely die of old age or cancer. Sadly, many large and giants breeds are prone to developing terminal illness at a relatively young age.

Tall dog, short lifespan

Across all breeds of dogs it holds true that the larger the breed, the shorter the dog’s life expectancy is. Researchers found out that the main reason for this is that large dogs age faster. Their body experiences age-related decay at much earlier ages than smaller dogs.

In giant breeds, any dog over the age of 6 years is considered a senior, while small dogs can still be spry and youthful at 12+ years old!

mastiff running

What do Mastiffs die from?

By being an observant dog owner you can prevent a Mastiff’s untimely death. Here is what you have to watch out for:

Bone cancer

The most common cause of death in Mastiffs is osteosarcoma (bone cancer). While there is no way to safely prevent this disease, early detection and treatment can prolong your dog’s life by a lot. Watch out for:

  • Swelling or lumps anywhere on your dog’s body
  • Sudden limping or licking of a paw or leg
  • Breathing difficulties
  • Seizures 
  • Unsteady gait

If you notice any of these signs, have your dog seen by a vet as soon as possible. Early detection and treatment is crucial in prolonging your Mastiff’s lifespan!

If you lost your Mastiff to bone cancer or another condition, Crossing the Rainbow Bridge is a wonderful resource for preserving their memory.


Lymphosarcome is a cancer of the lymphocytes (a type of blood cell) and lymphoid tissues.

Unfortunately, Mastiffs commonly suffer from this disease. Without treatment most dogs pass away within 1-2 months. If you detect this disease early and treat it well however, over 80% of dogs go into remission and can continue to live a happy life.

Watch out for:

  • Lethargy and loss of appetite
  • Weight loss
  • Enlarged lymph nodes
  • Fevers
  • Disinterest in everyday activities such as going for walks, playing or getting treats

As with bone cancer, early detection will give your Mastiff the best possible chance for successful treatment and a long and healthy life.

mastiff collar

Car accidents

Over 1.2 million dogs die as a result of being hit by cars in the US each year. Nearly all of these deaths are avoidable by taking proper precautions.

Genetic predisposition

Some Mastiffs have a genetic predisposition to develop certain cancers or illnesses. Ideally you should ask your puppy’s breeder about the health of the parents and grandparents.

Do not make the mistake of getting a Mastiff for the lowest possible price – instead, purchase your puppy from a reputable breeder. This will greatly increase the chances that your dog will live a long and healthy life.

How old is the oldest Mastiff?

The oldest known Mastiff was a dog named Kush. He lived in Australia from 1994-2009. While this is a great age, it is unfortunately not representative for the breed. 

Sadly, it is unusual for Mastiffs to live longer than 10-12 years. 

Why do Mastiffs have a short lifespan?

As explained above: Mastiffs have such a short lifespan because they age faster than smaller dogs. In addition, the high incidence of cancers in this breed contributes to a comparably low life expectancy.

You can considerably increase your dog’s chances for a long and happy life by feeding high quality food and taking him to regular checkups at his vet.

mastiff lifespan

The Bottom Line

Mastiffs live 6-12 years. These dogs are sadly prone to developing lymphoma and bone cancer. Regular preventative vet visits are key to increasing their lifespan. 

A healthy, high-quality diet will keep your dog in good shape and prevent the early onset of arthritis or diabetes. An ounce of prevention is worth a pound of cure when it comes to your Mastiff’s health.