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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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Caroline County ZIP Codes

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

County State ZIP Code City Area Codes
Caroline County MD 21609 Bethlehem 410
Caroline County MD 21629 Denton 302, 410, 443, 667
Caroline County MD 21632 Federalsburg 302, 410, 443, 667
Caroline County MD 21636 Goldsboro 302, 410, 443, 667
Caroline County MD 21639 Greensboro 302, 410, 443, 667
Caroline County MD 21640 Henderson 302, 410, 443, 667
Caroline County MD 21641 Hillsboro 410, 443, 667
Caroline County MD 21649 Marydel 302, 410, 443, 667
Caroline County MD 21655 Preston 410, 443, 667
Caroline County MD 21660 Ridgely 410, 443, 667
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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.