Bullmastiff

breed of dog

Also known as: bull mastiff

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Last updated

July 23, 2026

Quick Summary

The Bullmastiff is a breed of large working dog developed in 19th-century England. It is a cross between the Mastiff and the Bulldog, originally bred to discourage poaching on estates.

Origin: England
Height: 27.5–30 inches (70–76 cm)
Weight: 120–230 pounds (54–104 kg)
Lifespan: 6–10 years

Bullmastiffs are known for being powerful yet gentle, with a broad head, short muzzle, and short coat. They are affectionate with family but aloof with strangers and make intimidating watchdogs. Due to their size, they require ample space and can be expensive to feed. They are susceptible to overheating and have a shorter lifespan compared to some other breeds, with potential health concerns like bloat and hip dysplasia.1

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Mastiff
The slightly smaller Bullmastiff, a cross between the Mastiff and the Bulldog, was developed in 19th-century England; it was used chiefly to discourage poaching on estates and game preserves and was known as the “gamekeeper’s night-dog.” The Bullmastiff is a tan, reddish brown, or brindled dog, with black…
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The slightly smaller Bullmastiff, a cross between the Mastiff and the Bulldog, was developed in 19th-century England; it was used chiefly to discourage poaching on estates and game preserves and was known as the “gamekeeper’s night-dog.” The Bullmastiff is a tan, reddish brown, or brindled dog, with black…
Read More