New Castle County's estimated 2026 population is 590,038 with a growth rate of 0.34% in the past year according to the most recent United States census data. New Castle County is the largest county in Delaware. The 2010 population was 538,792 and has seen a growth of 9.51% since that time.
Data after 2023 is projected based on recent change
Overall: 39.3 years
Female: 40.6 years
Male: 38.2 years
There are 455,266 adults, (98,558 of whom are seniors) in New Castle County.
Female: 297,537 (51.5%)
Male: 280,424 (48.5%)
The racial composition of New Castle County includes 54.21% White, 25.55% Black or African American, 6.2% Asian, 5.25% other race, and smaller percentages for Native American, Native Hawaiian or Pacific Islander and multiracial populations.
Race | Population | Percentage (of total) |
|---|---|---|
| White | 313,334 | 54.21% |
| Black or African American | 147,685 | 25.55% |
| Two or more races | 49,249 | 8.52% |
| Asian | 35,810 | 6.2% |
| Other race | 30,351 | 5.25% |
| Native American | 1,320 | 0.23% |
| Native Hawaiian or Pacific Islander | 212 | 0.04% |
New Castle County's average per capita income is $58,563. Household income levels show a median of $91,166. The poverty rate stands at 10.14%.
Name | Median | Mean |
|---|---|---|
| Married Families | $136,923 | $165,410 |
| Families | $114,354 | $142,650 |
| Households | $91,166 | $120,512 |
| Non Families | $54,405 | $72,755 |
Average Income
Median Household Income
Poverty Rate