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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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Chester County ZIP Codes

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

County State ZIP Code City Area Codes
Westchester County NY 10603 White Plains 914
Westchester County NY 10604 West Harrison 203, 475, 914
Westchester County NY 10605 White Plains 914
Westchester County NY 10606 White Plains 914
Westchester County NY 10607 White Plains 914
Westchester County NY 10610 White Plains 914
Westchester County NY 10701 Yonkers 914
Westchester County NY 10702 Yonkers 914
Westchester County NY 10703 Yonkers 914
Westchester County NY 10704 Yonkers 347, 718, 914, 917, 929
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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.