How big does a Bullmastiff get? Adult weight is 100-130 lbs, and growing usually finishes around 24 months. The curve shows the weight to expect along the way.

Age	Expected weight
2 months	15-19.5 lbs
3 months	28.2-36.7 lbs
4 months	40.9-53.2 lbs
5 months	50.5-65.6 lbs
6 months	60-78 lbs
8 months	72-93.6 lbs
10 months	81.3-105.7 lbs
12 months	88-114.4 lbs
15 months	92.5-120.3 lbs
18 months	97-126.1 lbs
24 months	100-130 lbs

Typical range for a healthy puppy. Individual dogs can sit above or below it.

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Bullmastiff - Frequently Asked Questions

How big is a Bullmastiff? +

The Bullmastiff is a large breed, standing 24-27 in tall and weighing 100-130 lbs.

How much does a Bullmastiff weigh at 6 months? +

A Bullmastiff usually weighs 60-78 lbs at 6 months and reaches 100-130 lbs once fully grown, at around 24 months.

How long do Bullmastiffs live? +

The average lifespan of a Bullmastiff is 7-9 yrs.

How much does a Bullmastiff cost? +

Expect to pay $1,500-$3,000 for a Bullmastiff puppy, plus around $1,500-$2,500 per year for food, vet care, grooming, and supplies.

Is a Bullmastiff hypoallergenic? +

No, the Bullmastiff is not considered hypoallergenic and may trigger symptoms in people with dog allergies.

Is a Bullmastiff good with kids? +

The Bullmastiff can do well with older children, but supervision and early socialization are recommended around younger kids.

Is a Bullmastiff good for apartments? +

No - the Bullmastiff needs space and exercise that apartments rarely provide. A house with a yard is strongly recommended.

Is a Bullmastiff easy to train? +

The Bullmastiff is moderately trainable. Consistent, patient training from an early age works best.

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