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

Indiana ZIP Codes

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

State ZIP Code City County Area Codes
IN 46320 Hammond Lake County 219, 464, 708
IN 46321 Munster Lake County 219, 464, 708
IN 46322 Highland Lake County 219
IN 46323 Hammond Lake County 219
IN 46324 Hammond Lake County 219, 464, 708
IN 46325 Hammond Lake County 219
IN 46327 Hammond Lake County 219, 464, 708, 773, 872
IN 46340 Hanna LaPorte County 219, 574
IN 46341 Hebron Porter County 219
IN 46342 Hobart Lake County 219
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Geographic Map of Indiana

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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.