Alta Sierra (Spanish for "Upper Range") is a census-designated place (CDP) in Nevada County, California, United States.

There is a small commercial district with several restaurants, a gas station, a market and personal service businesses.

There is also another community called Alta Sierra in northcentral Kern County, CA near Lake Isabella.

The 2010 United States Census[24] reported that Alta Sierra had a population of 6,911.

580 households (20.5%) were made up of individuals, and 305 (10.8%) had someone living alone who was 65 years of age or older.

There were 3,030 housing units at an average density of 363.4 per square mile (140.3/km2), of which 2,403 (84.9%) were owner-occupied, and 427 (15.1%) were occupied by renters.

15.3% of all households were made up of individuals, and 8.7% had someone living alone who was 65 years of age or older.

In the state legislature, Alta Sierra is in the 1st Senate District, represented by Republican Megan Dahle,[26] and the 1st Assembly District, represented by Republican Heather Hadwick.

[27] Federally, Alta Sierra is in California's 3rd congressional district, represented by Republican Kevin Kiley.