Shandon is located at the bottom of the San Juan Valley, where San Juan Creek and Cholame Creek come together to form the Estrella River, which flows west to meet the Salinas River north of Paso Robles. Shandon is also at the junction of State Routes 41 and 46, at the southwestern portion of the stretch where the two highways merge together for approximately six miles. The even smaller town of Cholame is about six miles northeast of Shandon, where the two highways diverge again. The San Andreas Fault cuts perpendicular to the highways here, six miles from Shandon.
Grasslands and low hills surround the town, with the area immediately southwest of town being an agricultural region.
According to the United States Census Bureau, the CDP has a total area of 3.0 square miles (7.7 km²), all of it land.
As of the census of 2000, there were 986 people, 267 households, and 225 families residing in the CDP. The population density was 329.4 people per square mile (127.3/km²). There were 286 housing units at an average density of 95.5/sq mi (36.9/km²). The racial makeup of the CDP was 71.20% White, 0.51% African American, 0.61% Native American, 0.51% Asian, 20.59% from other races, and 6.59% from two or more races. Hispanic or Latino of any race were 47.67% of the population.
There were 267 households out of which 49.8% had children under the age of 18 living with them, 68.2% were married couples living together, 10.1% had a female householder with no husband present, and 15.4% were non-families. 10.9% of all households were made up of individuals and 3.4% had someone living alone who was 65 years of age or older. The average household size was 3.67 and the average family size was 3.86.
In the CDP the population was spread out with 34.7% under the age of 18, 13.6% from 18 to 24, 30.0% from 25 to 44, 15.6% from 45 to 64, and 6.1% who were 65 years of age or older. The median age was 26 years. For every 100 females there were 113.9 males. For every 100 females age 18 and over, there were 119.8 males.
The median income for a household in the CDP was $35,000, and the median income for a family was $32,273. Males had a median income of $28,068 versus $21,786 for females. The per capita income for the CDP was $11,174. About 16.7% of families and 22.9% of the population were below the poverty line, including 30.3% of those under age 18 and 13.6% of those age 65 or over.
In the state legislature Shandon is located in the 15th Senate District, represented by Republican Abel Maldonado, and in the 33rd Assembly District, represented by Republican Sam Blakeslee. Federally, Shandon is located in California's 22nd congressional district, which has a Cook PVI of R +16 and is represented by Republican Kevin McCarthy.
This part of the county's economy is largely based in agriculture. Several large vineyard plantings, including French Camp Vineyards represent important employers in the region.
Former Deputy Secretary of State, National Security Advisor, and United States Secretary of the Interior William P. Clark, Jr. resides near Shandon and has built a small chapel in the hills of his ranch. Current 2008-2009 National FFA Secretary Nessy Early is a resident of Shandon.