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U.S. ZIP Codes Database 2026

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Calhoun County ZIP Codes

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

County State ZIP Code City Area Codes
Calhoun County IA 50538 Farnhamville 515, 712
Calhoun County IA 50551 Jolley 712
Calhoun County IA 50552 Knierim 515, 712
Calhoun County IA 50563 Manson 515, 712
Calhoun County IA 50575 Pomeroy 712
Calhoun County IA 50579 Rockwell City 515, 712
Calhoun County IA 50586 Somers 515, 712
Calhoun County IA 51449 Lake City 712
Calhoun County IA 51453 Lohrville 515, 712
Calhoun County IL 62006 Batchtown 573, 618, 636
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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.