Farmington is a census-designated place (CDP) in San Joaquin County, California, United States. The population was 207 at the 2010 census, down from 262 at the 2000 census.
Farmington is located at 37°55′47″N 120°59′58″W / 37.92972°N 120.99944°W / 37.92972; -120.99944 (37.929625, -120.999574). According to the United States Census Bureau, the CDP has a total area of 2.5 square miles (6.6 km²), all of it land. The town has a school, firehouse, bar, Circle K, Shell gas station, general store, and post office. Barren, low hills and an excellent almond orchard lie to the immediate east of the town, and farther east are the Sierra Nevada mountains. Little Johnny Creek flows along the southern border of Farmington, paralleling Highway 4 for a short distance. The creek and many other places nearby were used as locations in the 1958 film The Big Country
The 2010 United States Census reported that Farmington had a population of 207. The population density was 81.4 people per square mile (31.4/km²). The racial makeup of Farmington was 164 (79.2%) White, 7 (3.4%) African American, 1 (0.5%) Native American, 6 (2.9%) Asian, 0 (0.0%) Pacific Islander, 18 (8.7%) from other races, and 11 (5.3%) from two or more races. Hispanic or Latino of any race were 42 persons (20.3%).