County ProfileDE
New Castle County
Population: 570,719 · 51 ZIP codes
Demographics
Source: U.S. Census Bureau (ACS/Decennial). Estimates vary by year.
People
Total population
570,719
People
Median age
39.3
Housing
Total households
224,173
Income
Median household income
$91,166
Housing
Total housing units
236,079
Employment
Employment rate
62.3%
Education
Bachelor’s degree or higher
39.7%
Healthcare
Insured population
94.1%
County details
Local time 03:14:40(ET)| Name | New Castle |
|---|---|
| Total ZIP codes | 51total |
| ZIP codes (by type) | 23 Standard11 PO Box17 Unique |
| Area code | 302 |
| Timezone | Eastern Time (ET) |
| Coordinates | 39.5759152, -75.6441324 |
| Land area | 426.3 sq miles(1,104.2 km²) |
Map of New Castle county, Delaware with ZIP codes
Cities and Communities in New Castle County
Compare the largest cities in New Castle County by population, median income, and growth. Use the table below to analyze key demographic shifts across the region.
| City | Population | Median incomeHousehold | ZIP codes |
|---|---|---|---|
| Wilmington | 70,898 | $58,671 | 25ZIPs |
| Newark | 30,601 | $76,912 | 10ZIPs |
| Middletown | 23,192 | $112,831 | 1ZIPs |
| Bear | 23,060 | $91,687 | 1ZIPs |
| Hockessin | 13,478 | $171,204 | 1ZIPs |
| Claymont | 9,895 | $74,712 | 1ZIPs |
| New Castle | 5,551 | $89,205 | 3ZIPs |
| Townsend | 2,717 | $153,000 | 1ZIPs |
| Saint Georges | 1,957 | $131,553 | 1ZIPs |
| Delaware City | 1,885 | $85,395 | 1ZIPs |
| Odessa | 366 | $123,750 | 1ZIPs |
| Rockland | 223 | — | 1ZIPs |
| Port Penn | 162 | $72,009 | 1ZIPs |
| Montchanin | 108 | — | 1ZIPs |
| Yorklyn | 34 | — | 1ZIPs |
| Winterthur | 16 | — | 1ZIPs |
— Data unavailable or suppressed by the U.S. Census Bureau for areas with small sample sizes to protect individual privacy.
ZIP Codes in New Castle County
Review the most populated postal areas across New Castle County. Use the ranking below to compare resident density and demographic scales between the county's major zones.
| ZIP | City | Median incomeHousehold | Population (ZIP) |
|---|---|---|---|
| 19720 | New Castle | $75,403 | 61,043 |
| 19702 | Newark | $92,446 | 55,653 |
| 19709 | Middletown | $132,956 | 49,599 |
| 19711 | Newark | $95,403 | 48,477 |
| 19701 | Bear | $111,198 | 42,717 |
| 19805 | Wilmington | $60,221 | 39,985 |
| 19808 | Wilmington | $94,234 | 39,285 |
| 19713 | Newark | $76,493 | 31,867 |
| 19802 | Wilmington | $53,812 | 26,189 |
| 19810 | Wilmington | $112,775 | 25,270 |
| 19803 | Wilmington | $135,218 | 21,886 |
| 19804 | Wilmington | $79,701 | 18,292 |
| 19707 | Hockessin | $172,696 | 17,274 |
| 19801 | Wilmington | $52,810 | 16,219 |
| 19703 | Claymont | $76,939 | 16,175 |
| 19809 | Wilmington | $81,288 | 14,658 |
| 19734 | Townsend | $127,803 | 14,116 |
| 19806 | Wilmington | $88,855 | 10,083 |
| 19807 | Wilmington | $153,341 | 8,089 |
| 19717 | Newark | — | 6,201 |
Data Sources & Citations
The geographic and demographic information presented on this site is compiled from publicly available, authoritative sources, including:
- United States Census BureauDemographic, population, housing, and socioeconomic data sourced from Census Bureau datasets, including the Decennial Census and the American Community Survey (ACS).Census Data
- United States Postal Service (USPS)ZIP code classifications, delivery types, and postal designations used for reference purposes. USPS ZIP codes are intended for mail delivery and may not always align exactly with Census geographic boundaries.USPS