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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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Day County ZIP Codes

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

County State ZIP Code City Area Codes
Day County SD 57219 Bristol 605
Day County SD 57239 Grenville 605
Day County SD 57261 Roslyn 605
Day County SD 57273 Waubay 605
Day County SD 57274 Webster 605
Day County SD 57422 Andover 605
Day County SD 57468 Pierpont 605

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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.