Vertical semiconductor devices having selectively regrown top contacts and method of fabricating vertical semiconductor devices having selectively regrown top contacts are described. For example, a semiconductor device includes a substrate having a surface. A first source/drain region is disposed on the surface of the substrate. A vertical channel region is disposed on the first source/drain region and has a first width parallel with the surface of the substrate. A second source/drain region is disposed on the vertical channel region and has a second width parallel with and substantially greater than the first width. A gate stack is disposed on and completely surrounds a portion of the vertical channel region.