At What Age Does a Puppy Stop Growing

He will grow to his full length at 18 months but males will continue to build muscle up to 3 years. Make sure you don't overexercise him in the first 12-18 months as while they're growing is when they are most susceptible to joint injuries.

Some dogs reach their full height quite early, like within a year but later develop their full muscular potential. Much like people in that respect, they might reach their full height potential by their mid to late teens and then start to "fill out" more in the years after that.

I think it really depends on the breed of dog. I think for many dogs it's somewhere between 18-months and 2 years old when they fill out their bone structure completely.

Someone else might be able to get more specific with regards to your golden retriever.

Hope this helps

Stacey