Contra Costa County's 2026 population is estimated at 1,193,463, reflecting a 0.88% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Contra Costa County is the 9th largest county in California. The 2010 population was 1,052,516 and has grown 13.39% since 2010.
Data after 2023 is projected based on recent change
Overall: 40.5 years
Female: 41.5 years
Male: 39.5 years
There are 909,012 adults, (199,270 of whom are seniors) in Contra Costa County.
Female: 592,046 (50.8%)
Male: 572,966 (49.2%)
The racial composition of Contra Costa County includes 41.12% White, 18.85% Asian, 13.93% other race, 8.28% Black or African American, and smaller percentages for Native American, Native Hawaiian or Pacific Islander and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 479,110 | 41.12% |
| Asian | 219,557 | 18.85% |
| Two or more races | 190,585 | 16.36% |
| Other race | 162,268 | 13.93% |
| Black or African American | 96,408 | 8.28% |
| Native American | 11,438 | 0.98% |
| Native Hawaiian or Pacific Islander | 5,646 | 0.48% |
Contra Costa County 's average per capita income is $71,603. Household income levels show a median of $127,229. The poverty rate stands at 8.36%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $174,901 | $225,542 |
| Families | $148,679 | $196,934 |
| Households | $127,229 | $174,872 |
| Non Families | $73,983 | $107,910 |
Average Income
Median Household Income
Poverty Rate