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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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Island County ZIP Codes

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

County State ZIP Code City Area Codes
Rock Island County IL 61257 Hillsdale 309, 779, 815
Rock Island County IL 61259 Illinois City 309, 319, 563
Rock Island County IL 61264 Milan 309, 563
Rock Island County IL 61265 Moline 309, 563
Rock Island County IL 61266 Moline 309
Rock Island County IL 61275 Port Byron 309, 563
Rock Island County IL 61278 Rapids City 309, 563
Rock Island County IL 61279 Reynolds 309
Rock Island County IL 61282 Silvis 309
Rock Island County IL 61284 Taylor Ridge 309
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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.