Contra Costa County, California
Contra Costa County: County in California, United States
About
Contra Costa County is a county located in the U.S. state of California. As of the 2010 census, the population was 1,049,025 and a population density of 505 people per km². After 10 years in 2020 county had an estimated population of 1,152,333 inhabitants. Its county seat is Martinez. The county was created 175 years ago in 1849.
Quick Facts about Contra Costa County
| Population : | 1,152,333 (2020) |
| Country : | United States of America |
| State : | California (United States) |
| Area : | 2078 km2 |
| Water as percent of area : | 10.93% |
| Land as percent of area : | 89.07% |
| Named for : | opposite coast |
| Altitude : | 499 feet / 152 meters |
| Capital : | Martinez |
| Establishment : | January 01, 1850 |
| Time Zone : | Pacific Time Zone |
| Local time : | 09:16:09 (22nd February 2025) |
| Density : | 555 Pop. per km² as of 2020 |
| Population growth : | 8.97% (2010-2020) |
Geography
Contra Costa County is located at 37°55'24"N 121°57'4"W (37.9234200, -121.9512100). It has 4 neighbors: Alameda County, Sacramento County, San Joaquin County and Solano County.
Contra Costa County map
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The largest city of Contra Costa County is Concord with a population of 128,544. Other cities include, Antioch population 111,605, Richmond population 110,038, San Ramon population 82,865 and Pittsburg population 72,622. See all Contra Costa County cities & populated places.
Contra Costa County Populated Places (more)
Cities, towns, neighborhoods & other populated places in Contra Costa County.
| City Name | Population | Title |
|---|---|---|
| Concord | 128,544 | The third most populous city in Contra Costa County, California. |
| Antioch | 111,605 | The most populous city in Contra Costa County, California. |
| Richmond | 110,038 | The most populous city in Contra Costa County, California. |
| San Ramon | 82,865 | A city in Contra Costa County, California. |
| Pittsburg | 72,622 | A city in Contra Costa County, California. |
| Walnut Creek | 69,936 | The fifth most populous city in Contra Costa County, California. |
| Brentwood | 65,017 | The most populous city in Contra Costa County, California. |
| Danville | 44,883 | Town in Contra Costa County, California |
| Oakley | 42,710 | A city in Contra Costa County, California. |
| Martinez | 38,027 | City in Contra Costa County, California, USA |
| Pleasant Hill | 34,781 | City in Contra Costa County, California, USA |
| San Pablo | 30,779 | City in Contra Costa County, California, United States |
| Hercules | 26,221 | City in western Contra Costa County, California |
| Lafayette | 25,992 | City in California |
| El Cerrito | 25,403 | City in Contra Costa County, California, United States |
| Bay Point | 21,534 | Census designated place in California |
- Official Website
Official website of Contra Costa County
Contra Costa County has 4 neighbours.
- Alameda County county in California, United States
- Sacramento County county in California, United States
- San Joaquin County county in California, United States
- Solano County county in California, United States of America
- Martinez
Demographics
The population of Contra Costa County increased by 8.97% in 10 years.
| Year | Population | % Change | Method |
| 2010 | 1,049,025 | - | census |
| 2011 | 1,065,440 | 1.54% | estimation process |
| 2012 | 1,077,548 | 1.12% | estimation process |
| 2013 | 1,093,401 | 1.45% | estimation process |
| 2014 | 1,108,876 | 1.4% | estimation process |
| 2015 | 1,124,405 | 1.38% | estimation process |
| 2016 | 1,137,268 | 1.13% | estimation process |
| 2017 | 1,145,535 | 0.72% | estimation process |
| 2018 | 1,150,519 | 0.43% | estimation process |
| 2019 | 1,153,526 | 0.26% | estimation process |
| 2020 | 1,152,333 | -0.1% | estimation process |
People born in Contra Costa County (12)
People born in Contra Costa County, including actress Amanda Detmer, musician John Kiffmeyer, composer Andrea Datzman, .
List
- Marc Bonilla (American musician) he was born in 03/07/1955
- Bob Gaillard (American basketball player-coach) he was born in 23/10/1940
- Ron Luce (American evangelist) he was born in 11/07/1961
- William Jefferson Hunsaker (American lawyer) he was born in 21/09/1855
- Frank Henry Kerrigan (United States federal judge) he was born in 17/09/1868
- Dino Waldren (American rugby union player) he was born in 11/07/1991
- Anthony Sadler (American actor, television personality and writer) he was born in 13/07/1992
- Carolyn Rouse (American anthropologist) she was born in 20/07/1965
- Flavia Camilla (American actress)
California Other Counties (more counties)
| County Name | Population | Title |
|---|---|---|
| Los Angeles County | 9,943,046 | County in California, United States of America |
| Los Angeles | 3,970,219 | The second most populous city in the United States and the center of the Los Angeles metropolitan area. |
| San Diego County | 3,332,427 | San Diego County, founded in 1850, is one of 58 counties in the US state of California. |
| Orange County | 3,166,857 | County in California, United States |
| Riverside County | 2,489,188 | County in California, United States |
| San Bernardino County | 2,189,183 | County in California, United States |
| Santa Clara County | 1,907,105 | County in California, United States |
| Alameda County | 1,662,323 | County in California, United States |
| Sacramento County | 1,559,146 | County in California, United States |
| San Diego | 1,422,420 | The eighth most populous city in the United States and the center of the San Diego metropolitan area. |
| Laguna | 1,370,232 | A city located in Orange County, California. |
| San Jose | 1,013,616 | The tenth most populous city in the United States and the center of the San Jose metropolitan area. |
| Fresno County | 1,000,918 | County in California, United States |
| Kern County | 901,362 | |
| San Francisco County | 866,606 | County, coextensive with the city of San Francisco, California, United States |
| San Francisco | 866,606 | The seventeenth most populous city in the United States and the center of the San Francisco Bay Area. |
