As of the census of 2000, there were 15,440 people, 3,997 households, and 2,937 families residing in the area. The population density was 13,221.9 people per square mile (5,095.2/km²). There were 4,059 housing units at an average density of 3,475.9/sq mi (1,339.5/km²). The racial makeup of the CDP was 36.60% White, 5.92% African American, 0.94% Native American, 1.03% Asian, 3.51% Pacific Islander, 39.94% from other races, and 5.35% from two or more races. Hispanic or Latino of any race were 86.57% of the population.
There were 3,997 households out of which 45.2% had children under the age of 18 living with them, 53.0% were married couples living together, 12.2% had a female householder with no husband present, and 26.5% were non-families. 18.0% of all households were made up of individuals and 4.4% had someone living alone who was 65 years of age or older. The average household size was 3.81 and the average family size was 4.20.
In the area the population was spread out with 30.3% under the age of 18, 12.4% from 18 to 24, 35.8% from 25 to 44, 15.9% from 45 to 64, and 5.6% who were 65 years of age or older. The median age was 29 years. For every 100 females there were 115.2 males. For every 100 females age 18 and over, there were 117.9 males.
The median income for a household in the area was $55,603, and the median income for a family was $54,678. Males had a median income of $32,169 versus $27,578 for females. The per capita income for the CDP was $18,331. About 11.7% of families and 15.4% of the population were below the poverty line, including 17.1% of those under age 18 and 6.8% of those age 65 or over. Although this median income is nearly $13,500 above the national average, North Fair Oaks is still classified as a low-income, minority-majority community. Due to the extremely high cost of living (considering that the community borders Atherton and other wealthy communities), wage inflation occurs, where many working-class families earn over $50,000 a year performing the same jobs that in other parts in the country (such as in the restaurant industry) would only pay $25,000 a year. Because of the high cost of living, however, the amount of disposable income remains the same.