U.S. postal lookup

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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Nassau County ZIP Codes

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

County State ZIP Code City Area Codes
Nassau County NY 11551 Hempstead 516
Nassau County NY 11552 West Hempstead 363, 516
Nassau County NY 11553 Uniondale 363, 516
Nassau County NY 11554 East Meadow 363, 516
Nassau County NY 11555 Uniondale 516
Nassau County NY 11556 Uniondale 363, 516
Nassau County NY 11557 Hewlett 363, 516
Nassau County NY 11558 Island Park 363, 516
Nassau County NY 11559 Lawrence 347, 363, 516, 718, 917, 929
Nassau County NY 11560 Locust Valley 363, 516
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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.