As of the census of 2000, there were 12,260 people, 4,676 households, and 3,170 families residing in the CDP. The population density was 3,953.1 people per square mile (1,527.0/km²). There were 4,803 housing units at an average density of 1,548.7/sq mi (598.2/km²). The racial makeup of the CDP was 60.35% White, 12.16% Black or African American, 0.67% Native American, 12.50% Asian, 0.29% Pacific Islander, 6.97% from other races, and 7.06% from two or more races. 15.58% of the population were Hispanic or Latino of any race.
There were 4,676 households out of which 32.6% had children under the age of 18 living with them, 47.6% were married couples living together, 14.8% had a female householder with no husband present, and 32.2% were non-families. 24.6% of all households were made up of individuals and 8.3% had someone living alone who was 65 years of age or older. The average household size was 2.61 and the average family size was 3.11.
In the CDP the population was spread out with 24.7% under the age of 18, 7.3% from 18 to 24, 31.0% from 25 to 44, 25.2% from 45 to 64, and 11.8% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 94.1 males. For every 100 females age 18 and over, there were 92.2 males.
The median income for a household in the CDP was $48,272, and the median income for a family was $59,342. Males had a median income of $44,232 versus $34,661 for females. The per capita income for the CDP was $24,525. About 6.6% of families and 9.5% of the population were below the poverty line, including 9.5% of those under age 18 and 10.7% of those age 65 or over.
El Sobrante is also home to a growing Sikh population, one of the largest in the San Francisco Bay Area and western United States. The center of the Sikh community is the Gurdwara Sahib of El Sobrante (known for its large golden dome) which sits high in the hills above San Pablo Dam Road.