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U.S. ZIP Codes Database 2026

Search by ZIP code, city, county, or state and find clear postal details with maps, time zones, and area code data.

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New Castle County ZIP Codes

Browse all ZIP Codes, cities, and associated area codes registered in New Castle County.

County State ZIP Code City Area Codes
New Castle County DE 19730 Odessa 302
New Castle County DE 19731 Port Penn 302
New Castle County DE 19732 Rockland 302
New Castle County DE 19733 Saint Georges 302
New Castle County DE 19734 Townsend 302, 410, 443, 667
New Castle County DE 19735 Winterthur 302
New Castle County DE 19736 Yorklyn 302
New Castle County DE 19801 Wilmington 302
New Castle County DE 19802 Wilmington 302
New Castle County DE 19803 Wilmington 302, 484, 610, 835
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About U.S. ZIP Codes

ZIP codes are a United States Postal Service system introduced in 1963 to make mail routing more accurate and efficient. The standard format uses five digits, while ZIP+4 adds four more digits for a more precise delivery segment.

ZIP codes cover the United States, its territories, military mail routes, and other USPS delivery points. This directory organizes that data for practical lookup by ZIP code, city, county, and state.