Best food for Bullmastiff puppy

Bullmastiffs are exactly the breed where getting puppy food right really matters — they grow fast and heavy, and overfeeding or using the wrong formula can put serious strain on developing joints. Before I give you a straight answer, a couple of quick things: is your puppy home with you already, and what have they been eating so far — did the breeder send you away with anything, or are you starting from scratch?

That confusion is completely understandable — and honestly, a lot of it comes from advice written for dogs in general, not for a Bullmastiff specifically. Here's the thing with giant and large breed puppies: calcium and phosphorus ratios matter a lot. If those are too high during growth, you get abnormal bone development — conditions like HOD or OCD that are painful and expensive. Generic puppy foods aren't formulated with that in mind. Raw feeding can work but it requires real knowledge to balance correctly, and getting it wrong at this age on a dog this size has consequences. At 11 weeks on a supermarket food, you're not in crisis, but switching now to something properly calibrated is the right move. What's his weight currently, roughly?

8kg at 11 weeks is a good solid weight for a Bullmastiff — he's going to be a big lad. The recommendation I'd give you is Royal Canin Maxi Puppy. I know the brand gets some eye-rolls online, but for large breed puppies it genuinely does what it says: the calcium and phosphorus levels are carefully controlled, the kibble size is right for a puppy jaw that size, and the protein level supports muscle development without forcing excessive growth rate. That last part is crucial for Bullmastiffs — you don't want him growing faster than his skeleton can handle. It's widely available on Amazon UK, easy to transition onto, and the feeding guidelines on the bag are actually reliable if you follow them by weight. Transition slowly over about a week — mix it into what he's currently eating, starting with about 25% new food and working up.

Good question, and it's worth thinking about. Bullmastiffs sit in a slightly awkward middle ground — males typically top out around 50–60kg, which is large rather than true giant. Royal Canin's Maxi Puppy covers breeds up to around 44kg adult weight, and Giant Puppy covers above that. For a Bullmastiff, Giant Puppy is actually the better fit — it has a longer feeding window (up to 18–24 months) which suits the slower maturation of big dogs, and the growth-rate management is more conservative. So to revise my recommendation slightly: go with Royal Canin Giant Puppy rather than Maxi. Same logic, just better matched to where he's going to end up.

At 11 weeks he'll be eating roughly 300–350g a day, increasing as he grows — the bag has a weight-based chart which is your actual guide. A 15kg bag will last you maybe 5–6 weeks right now, less as he gets bigger. As for switching to adult food: with a Bullmastiff, don't rush it. Most large and giant breed dogs shouldn't move to adult food until 18–24 months — the puppy formula's controlled calcium levels are doing a job right up until skeletal maturity. Royal Canin Giant Puppy is actually designed to be fed until 18–24 months depending on the dog. Your vet can confirm when he's close to his adult size. The short version: don't switch early just because he looks grown up — Bullmastiffs look nearly adult way before their bones are done.