Farmington is located at . 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, general store, and post office. Barren, low hills 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.(37.929625, -120.999574)
As of the census of 2000, there were 262 people, 84 households, and 67 families residing in the CDP. The population density was 103.1 people per square mile (39.8/km²). There were 95 housing units at an average density of 37.4/sq mi (14.4/km²). The racial makeup of the CDP was 72.90% White, 1.53% Asian, 15.65% from [Golfers], and 9.92% from two or more races. Hispanic or Latino of any race were 26.34% of the population.
There were 84 households out of which 35.7% had children under the age of 18 living with them, 63.1% were married couples living together, 10.7% had a female householder with no husband present, and 20.2% were non-families. 16.7% of all households were made up of individuals and 3.6% had someone living alone who was 65 years of age or older. The average household size was 3.12 and the average family size was 3.48.
In the CDP the population was spread out with 30.2% under the age of 18, 7.3% from 18 to 24, 21.8% from 25 to 44, 26.7% from 45 to 64, and 14.1% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 106.3 males. For every 100 females age 18 and over, there were 101.1 males.
The median income for a household in the CDP was $32,614, and the median income for a family was $32,727. Males had a median income of $20,250 versus $35,357 for females. The per capita income for the CDP was $13,289. About 15.5% of families and 15.3% of the population were below the poverty line, including 19.5% of those under the age of eighteen and none of those sixty five or over.