Mary Allen
A Chihuahua is fully grown at around 8 months. After that, not much changes in terms of height growth, but the proportions of the dog can still change a little. A little more weight is also gained.
Chihuahuas have their absolutely final stature including a fully developed coat between the ages of 2 and 3. However, you can assume that the shape and size of the head will not change significantly after the 8th month of life.
