Population
Population
topographic
Population

Contra Costa County

1,165,927
Total Population in 2020
In 2020, Contra Costa County was home to 1,165,927 people. Residents were predominantly working age, while those under 18 were a larger segment of the county than those 65 and older. The population was diverse, with no racial group in the majority.

Most Populous Demographics

CategoryDemographicTotalPercentage
Age18-64709,87361%
SexFemale597,86151%
Race and Hispanic or LatinoWhite (Not Hispanic or Latino)455,42139%

Age

40.1
Median Age
In 2020, Contra Costa County's population was a majority working-age adults, while those under age 18 were a moderately larger share of the county than those 65 and older. Looking at 10-year age ranges, 50-59 was the largest group.

Population by Age Range

040k80k120k160k0-910-1920-2930-3940-4950-5960-6970-7980+11%14%11%13%14%14%12%7%4%
040k80k120k160k11%14%11%13%14%14%12%7%4%0-910-1920-2930-3940-4950-5960-6970-7980+
/View Population by Age Range dynamic table

Population by Age Group

61%18-64
    263,255
    Under 18
    709,873
    18-64
    192,799
    65 and over
/View Population by Age Group dynamic table

Table: Population by Age Range

Age RangePopulation in Contra Costa County
TotalPercentage
0-9133,94511%
10-19158,51514%
20-29132,67611%
30-39156,85313%
40-49158,03514%
50-59159,76414%
60-69134,83412%
70-7986,4117%
80+44,8944%

Table: Population by Age Group

Age GroupPopulation in Contra Costa County
TotalPercentage
Under 18263,25523%
18-64709,87361%
65 and over192,79917%
* For both charts above, the data is collected from the U.S. Census Bureau Decennial Data 2020, Demographic and Housing Characteristics File (DHC), P12 Sex by Age for Selected Age Categories.

Sex and Age

In 2020, females outnumbered males by a moderate amount in Contra Costa County. Females 50-59 were the largest group by age, followed by males 10-19 and females 40-49. The biggest gap was in the 70-79 age group, where females were the larger share.

Population by Sex

51%Female
    568,066
    Male
    597,861
    Female
/View Population by Sex dynamic table

Population by Sex and Age

025k50k75k100k0-910-1920-2930-3940-4950-5960-6970-7980+68,25581,28067,50276,74776,74177,66763,41238,63617,82665,69077,23565,17480,10681,29482,09771,42247,77527,068
025k50k75k100k0-910-1920-2930-3940-4950-5960-6970-7980+68,25581,28067,50276,74776,74177,66763,41238,63617,82665,69077,23565,17480,10681,29482,09771,42247,77527,068
100k75k50k25k025k50k75k100k0-910-1920-2930-3940-4950-5960-6970-7980+68,25581,28067,50276,74776,74177,66763,41238,63617,82665,69077,23565,17480,10681,29482,09771,42247,77527,068
/View Population by Sex and Age dynamic table
Male
Female

Table: Population by Sex

SexContra Costa County
TotalPercentage
Male568,06649%
Female597,86151%

Table: Population by Sex and Age

Sex and AgeContra Costa County
TotalPercentage
Male568,06649%
Male: 0-968,2556%
Male: 10-1981,2807%
Male: 20-2967,5026%
Male: 30-3976,7477%
Male: 40-4976,7417%
Male: 50-5977,6677%
Male: 60-6963,4125%
Male: 70-7938,6363%
Male: 80+17,8262%
Female597,86151%
Female: 0-965,6906%
Female: 10-1977,2357%
Female: 20-2965,1746%
Female: 30-3980,1067%
Female: 40-4981,2947%
Female: 50-5982,0977%
Female: 60-6971,4226%
Female: 70-7947,7754%
Female: 80+27,0682%
* For both charts above, the data is collected from the U.S. Census Bureau Decennial Data 2020, Demographic and Housing Characteristics File (DHC), P12 Sex by Age for Selected Age Categories.

Race and Hispanic or Latino

39%
White (Not Hispanic or Latino)
In 2020, Contra Costa County had a diverse population with no race/ethnicity being a majority. White and Hispanic people were the largest groups in the county, while Asian and Black residents were the next biggest segments of the population.

Population by Race and Hispanic or Latino

0150k300k450k600kWhite*Black or African American*American Indian / Alaska Native*Asian*Native Hawaiian / Pacific Islander*Other / Multi-racial*Hispanic or Latino (any race)39%8%<1%18%<1%6%27%
0150k300k450k600kWhite*Black or African American*American Indian / Alaska Native*Asian*Native Hawaiian / Pacific Islander*Other / Multi-racial*Hispanic or Latino (any race)39%8%<1%18%<1%6%27%
0150k300k450k600kWhite*Black or African American*American Indian / Alaska Native*Asian*Native Hawaiian / Pacific Islander*Other / Multi-racial*Hispanic or Latino (any race)39%8%<1%18%<1%6%27%
/View Population by Race and Hispanic or Latino dynamic table

Table: Population by Race and Hispanic or Latino

Race and Hispanic or LatinoPopulation in Contra Costa County
TotalPercentage
White455,42139%
Black or African American97,9948%
American Indian / Alaska Native2,553<1%
Asian214,52018%
Native Hawaiian / Pacific Islander5,720<1%
Other / Multi-racial74,8196%
Hispanic or Latino (any race)314,90027%
* Categorized as Not Hispanic. This means that all the racial groups marked with an asterisk — White, Black or African American, American Indian / Alaska Native, Asian, Native Hawaiian / Pacific Islander, and Other / Multi-racial — do not include individuals who identify as Hispanic or Latino. The "Hispanic or Latino (any race)" category is separate, as Hispanic/Latino is considered an ethnicity rather than a racial category. For the chart above, the data is collected from the U.S. Census Bureau Decennial Data 2020, Demographic and Housing Characteristics File (DHC), P5 Hispanic or Latino Origin by Race.