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U.S. ZIP Codes Database 2026

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Dubuque County ZIP Codes

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

County State ZIP Code City Area Codes
Dubuque County IA 52001 Dubuque 563, 608
Dubuque County IA 52002 Dubuque 563
Dubuque County IA 52003 Dubuque 563, 779, 815
Dubuque County IA 52004 Dubuque 563
Dubuque County IA 52032 Bernard 563
Dubuque County IA 52033 Cascade 319, 563
Dubuque County IA 52039 Durango 563
Dubuque County IA 52040 Dyersville 563
Dubuque County IA 52045 Epworth 563
Dubuque County IA 52046 Farley 563
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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.