Sierra County, California

Sierra County
Interactive map of Sierra County
Location in the state of California
Country United States
State California
RegionSierra Nevada
IncorporatedApril 16, 1852
Named afterSierra Nevada
County seatDownieville
Largest cityLoyalton
Government
 • TypeCouncil–Manager
 • ChairPaul Roen
 • Vice ChairSharon Dryden
 • Board of Supervisors
Supervisors
  • Lee Adams
  • Lila Heuer
  • Paul Roen
  • Terry LeBlanc
  • Sharon Dryden
Area
 • Total
962 sq mi (2,490 km2)
 • Land953 sq mi (2,470 km2)
 • Water9 sq mi (23 km2)
Highest elevation
8,844 ft (2,696 m)
Population
 • Total
3,236
 • Density3.40/sq mi (1.31/km2)
GDP
 • Total$0.114 billion (2022)
Time zoneUTC-8 (Pacific Standard Time)
 • Summer (DST)UTC-7 (Pacific Daylight Time)
Area code530
Congressional district3rd
Websitewww.sierracounty.ca.gov

Sierra County (/siˈɛrə/ ) is a county located in the U.S. state of California. As of the 2020 census, the population was 3,236, making it California's second-least populous county. The county seat is Downieville; the sole incorporated city is Loyalton. The county is in the Sierra Nevada, northeast of Sacramento on the border with Nevada.