When do Tosa Inus stop growing?

Tosa Inus typically stop growing in height by 12 to 18 months, although they will continue to build muscle mass and fill out until they’re about three years old. These large, muscular dogs take a bit longer to fully mature than smaller breeds. 

Since their growth slows down around 12 to 18 months, it’s a good idea to switch them to adult food around that time. Consult your vet to ensure they’re transitioning at the right time based on their specific growth and development.