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 21042 Ellicott City Howard County 410, 443, 667
MD 21043 Ellicott City Howard County 410, 443, 667
MD 21044 Columbia Howard County 227, 240, 301, 410, 443, 667
MD 21045 Columbia Howard County 410, 443, 667
MD 21046 Columbia Howard County 227, 240, 301, 410, 443, 667
MD 21047 Fallston Harford County 410, 443, 667
MD 21048 Finksburg Carroll County 410, 443, 667
MD 21050 Forest Hill Harford County 410, 443, 667
MD 21051 Fork Baltimore County 410, 443, 667
MD 21052 Fort Howard Baltimore County 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.