The sources for Farmington Branch are on the northern end of Kessler Mountain and on the south side of Millsaps Mountain north of the intersection Old Farmington Road and West Steppingstone Drive.
The North Fork of the branch runs south around the base of Washington Mountain. The South Fork begins high up in the hollow below Deepwood.
The confluence of these tributaries forms Farmington Branch, which flows west paralleling U.S. Highway 62 and then around the north side of Farmington before turning north and joining Goose Creek.