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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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Oswego County ZIP Codes

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

County State ZIP Code City Area Codes
Oswego County NY 13167 West Monroe 315, 680
Oswego County NY 13302 Altmar 315, 680
Oswego County NY 13426 Orwell 315
Oswego County NY 13437 Redfield 315, 680
Oswego County NY 13493 Williamstown 315, 680
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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.