When is a shih tzu full grown?

A shih tzu is full-grown by 15 months. Most reach adulthood within a year, and some stop growing at 9-11 months. By 6-8 months they’ll have reached their maximum height.

Fully grown, they’ll weigh between 9lbs and 16lbs and stand between 9” and 10.5’’ high at the shoulder. With their stocky build, and curled-up tails, they’re almost brick-shaped, only a bit longer than they are tall.