The CDP is in the northern part of the town of Farmington, in the valley of the Cocheco River and surrounding rural land.

It is bordered to the northeast by the town of Milton, to the north by Middleton, and to the northwest by New Durham.

New Hampshire Route 153 is Farmington's Main Street, leading north 8 miles (13 km) to Union.

According to the U.S. Census Bureau, the Farmington CDP has a total area of 6.3 square miles (16.2 km2), all of it recorded as land.

[4] The Cocheco River passes through the western and southern parts of the CDP, flowing southeast to Rochester and Dover.