County Dossier

Marin County

California | County

Population

257,969

Land Area

520.1 sq mi

Context

Metro

Geography

County silhouette

Land Area
520.1 sq mi
Water Area
308.0 sq mi
Water Share
37.2%

Terrain Layer

Open the county terrain view inside the atlas flow.

Terra Firma

Population & Housing

Population

257,969

Density
496.0 / sq mi
Households
103,018
Housing Units
112,116
Median Age
47.4 years

Income & Economy

Median Household Income

$149,091

GDP

$36.85B

Real GDP Change+1.8%
Per Capita Income
$93,920
Personal Income
$48.94B
Personal Income Per Capita
$190,891

Classification

RUCC 1
Metro

Counties in metro areas of 1 million population or more

Relief

Min

-336 ft

Mean

273 ft

Max

2,575 ft

Provenance

GEOID 06041 ANSI 00277285
Latitude 38.05137 Longitude -122.74640
Canonical 2025 Gazetteer ACS ACS 2020-2024 5-year BEA BEA county 2024 release (2026-02-05) BLS BLS LAUS 2024 annual average USDA USDA RUCC 2023 USGS USGS 3DEP published as of 2026-03-23