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.

42,735 verified records
All states and U.S. territories
Maps and coordinates
County directory

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 11576 Roslyn 363, 516
Nassau County NY 11577 Roslyn Heights 363, 516
Nassau County NY 11579 Sea Cliff 363, 516
Nassau County NY 11580 Valley Stream 347, 363, 516, 718, 917, 929
Nassau County NY 11581 Valley Stream 347, 363, 516, 718, 917, 929
Nassau County NY 11582 Valley Stream 516
Nassau County NY 11590 Westbury 363, 516
Nassau County NY 11592 Rockville Center 516
Nassau County NY 11594 Westbury 516
Nassau County NY 11595 Westbury 516
Page 8 of 12

Geographic Map of Nassau County

Postal context

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.