New Castle County's estimated 2025 population is 585,268 with a growth rate of 0.57% in the past year according to the most recent United States census data. New Castle County is the 1st largest county in Delaware. The 2010 population was 538,792 and has seen a growth of 8.63% since that time.
Data after 2023 is projected based on recent change
The racial composition of New Castle County includes 56.48% White, 25.28% Black or African American, 5.93% Asian, 4.68% other race, and smaller percentages for Native American, Native Hawaiian or Pacific Islander and multiracial populations.
Race | Population | Percentage (of total) |
|---|---|---|
| White | 323,642 | 56.48% |
| Black or African American | 144,850 | 25.28% |
| Two or more races | 42,367 | 7.39% |
| Asian | 33,953 | 5.93% |
| Other race | 26,823 | 4.68% |
| Native American | 1,177 | 0.21% |
| Native Hawaiian or Pacific Islander | 218 | 0.04% |
Married
Widowed
Divorced
Separated
Never Married
New Castle County's average per capita income is $57,648. Household income levels show a median of $89,901. The poverty rate stands at 10.2%.
Name | Median | Mean |
|---|---|---|
| Married Families | $134,580 | $162,092 |
| Families | $112,402 | $140,270 |
| Households | $89,901 | $118,003 |
| Non Families | $54,382 | $71,246 |
Average Income
Median Household Income
Poverty Rate