County Maps US

Siskiyou County, California

A county in California, ranked 45 of 58 by population.

CountyFIPS 06093

Within California
Siskiyou County, highlighted, with the areas around it. Boundaries generalised from the 2025 Census cartographic boundary file; neighbour fills carry no data. The dot marks Yreka, the county seat, located via the 2025 Census Gazetteer.

Download SVGFull California map downloads

Population
42,013
-1,970 (-4.5%) since 2020
Land area
6,279
square miles. A further 1.1% of the total area is water
Population density
6.7
people per square mile, computed rather than published
County seat
Yreka
Seat of county government.
Established
1852
173 years ago
Largest city
Yreka city
Population 7,714.

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; Wikidata (CC0), Wikidata. Retrieved 30 August 2026.

Satellite view

Aerial imagery of Siskiyou County with its boundary drawn on top. A map shows you the shape; this shows you what is inside it, and which side of the line a place falls on.

Aerial view of Siskiyou County, California from the USGS National Map, with its boundary outlined
Imagery: USGS National Map, USGS Imagery Only, public domain, requested from USGS by your browser when you reach this point on the page, at 800 by 513 pixels. The boundary is the 2025 Census cartographic boundary file, reprojected to Web Mercator to match the imagery. You can also open the USGS National Map viewer.

Where Siskiyou County ranks

Position among the 58 counties of California, and among all 3,144 US counties and county-equivalents. Computed from the figures on this page.

MeasureValueIn CaliforniaNationally
Population42,01345th of 581,154th of 3,144
Land area6,279 sq mi5th of 5854th of 3,144
Population density6.7 per sq mi51st of 582,699th of 3,144
Median household income$59,09556th of 582,161st of 3,143

Full data for Siskiyou County

Every figure below is attributed to the Census Bureau product it came from, with the vintage of that product.
MeasureValueSource and vintage
Population42,013Vintage 2025 Population Estimates
Population in 202043,983Vintage 2025 Population Estimates
2020 estimates base?44,076Vintage 2025 Population Estimates
Land area6,279 sq mi2025 Gazetteer Files
Water area69.2 sq mi2025 Gazetteer Files
Total area6,348 sq mi2025 Gazetteer Files
Population density?6.7 per sq miComputed: Vintage 2025 estimates divided by 2025 Gazetteer land area
Median household income$59,095American Community Survey 2020-2024 5-Year Estimates
Median home value$309,500American Community Survey 2020-2024 5-Year Estimates
Median age47.2American Community Survey 2020-2024 5-Year Estimates
Households19,079American Community Survey 2020-2024 5-Year Estimates
Housing units23,088American Community Survey 2020-2024 5-Year Estimates

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; US Census Bureau, American Community Survey, American Community Survey 2020-2024 5-Year Estimates, released 29 January 2026. Population density is computed here, not published: it divides the Vintage 2025 population estimate by the 2025 Gazetteer land area, which are two different Census products. Retrieved 30 August 2026.

How the population changed

The Census Bureau publishes the components behind an estimate, not just the total. For the year to July 2025:

Births minus deaths
-281
320 births, 601 deaths
Net migration
-198
More people moved out than moved in.

Source: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026. Retrieved 30 August 2026.

The 8 areas bordering Siskiyou County

Ordered by the length of the border actually shared, which the Census Bureau publishes in its county adjacency file and which no other county reference presents.

Bordering areaStateShared borderPopulation
Trinity CountyCalifornia105 mi15,720
Del Norte CountyCalifornia66 mi26,410
Modoc CountyCalifornia57 mi8,426
Shasta CountyCalifornia55 mi181,648
Jackson CountyOregon49 mi221,795
Klamath CountyOregon43 mi70,274
Humboldt CountyCalifornia26 mi131,647
Josephine CountyOregon15 mi87,867

Source: US Census Bureau, County Adjacency File, 2025 County Adjacency File, released 15 September 2025. Retrieved 30 August 2026.

All 58 counties of California

Open the interactive California county map, or jump straight to any of them.

Data on this page last rebuilt 30 August 2026. How these figures are produced.