U.S. postal lookup

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.

42,735 verified records
All states and U.S. territories
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State directory

Maryland ZIP Codes

Complete postal directory, details, and geographic map for the State of Maryland.

State ZIP Code City County Area Codes
MD 21029 Clarksville Howard County 227, 240, 301, 410, 443, 667
MD 21030 Cockeysville Baltimore County 410, 443, 667
MD 21031 Hunt Valley Baltimore County 410, 443, 667
MD 21032 Crownsville Anne Arundel County 410, 443, 667
MD 21034 Darlington Harford County 410, 443, 667
MD 21035 Davidsonville Anne Arundel County 227, 240, 301, 410, 443, 667
MD 21036 Dayton Howard County 227, 240, 301, 410, 443, 667
MD 21037 Edgewater Anne Arundel County 410, 443, 667
MD 21040 Edgewood Harford County 410, 443, 667
MD 21041 Ellicott City Howard County 410
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Geographic Map of Maryland

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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.