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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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Whiteside County ZIP Codes

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

County State ZIP Code City Area Codes
Whiteside County IL 61037 Galt 779, 815
Whiteside County IL 61071 Rock Falls 779, 815
Whiteside County IL 61081 Sterling 779, 815
Whiteside County IL 61230 Albany 309, 563, 779, 815
Whiteside County IL 61243 Deer Grove 779, 815
Whiteside County IL 61250 Erie 309, 779, 815
Whiteside County IL 61251 Fenton 309, 779, 815
Whiteside County IL 61252 Fulton 309, 563, 779, 815
Whiteside County IL 61261 Lyndon 309, 779, 815
Whiteside County IL 61270 Morrison 309, 779, 815
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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.