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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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Allendale County ZIP Codes

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

County State ZIP Code City Area Codes
Allendale County SC 29810 Allendale 803, 839, 912
Allendale County SC 29827 Fairfax 803, 839, 843, 854
Allendale County SC 29836 Martin 478, 803, 839, 912
Allendale County SC 29846 Sycamore 803
Allendale County SC 29849 Ulmer 803, 839

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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.