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Iowa Zip Codes



Iowa Iowa is a state located in the Midwestern United States, an area often referred to as the "American Heartland". It derives its name from the Ioway people, one of the many American Indian tribes that occupied the state at the time of European exploration. Iowa was a part of the French colony of New France. After the Louisiana Purchase, settlers laid the foundation for an agriculture-based economy in the heart of the Corn Belt. Iowa is often known as the "Food Capital of the World".

In the latter half of the 20th century, Iowa s agricultural economy transitioned to a diversified economy of advanced manufacturing, processing, financial services, biotechnology, and green energy production. Iowa is the 26th most extensive and the 30th most populous of the 50 United States. Its capital and largest city is Des Moines. Iowa has been listed as one of the safest states to live in.

State Zip Code City County Area Codes
IA 51054 Sergeant Bluff Woodbury County 402, 531, 712
IA 51055 Sloan Woodbury County 402, 531, 712
IA 51056 Smithland Woodbury County 712
IA 51058 Sutherland O'Brien County 712
IA 51060 Ute Monona County 712
IA 51061 Washta Cherokee County 712
IA 51062 Westfield Plymouth County 605, 712
IA 51063 Whiting Monona County 402, 531, 712
IA 51101 Sioux City Woodbury County 712
IA 51102 Sioux City Woodbury County 712
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Map of Iowa

ZIP codes are a system of postal codes used by the United States Postal Service (USPS) since 1963. The term ZIP, an acronym for Zone Improvement Plan, is properly written in capital letters and was chosen to suggest that the mail travels more efficiently, and therefore more quickly, when senders use the code in the postal address. The basic format consists of five decimal numerical digits. An extended ZIP+4 code, introduced in the 1980s, includes the five digits of the ZIP code, a hyphen, and four more digits that determine a more precise location than the ZIP code alone. The term ZIP code was originally registered as a servicemark (a type of trademark) by the U.S. Postal Service, but its registration has since expired.

ZIP codes designate only delivery points within the United States and its dependencies, as well as locations of its armed forces. There are no ZIP codes reserved for designating mail bound for foreign destinations (with the exception of U.S. military units stationed outside of the United States), and therefore, international outbound mail should not include a ZIP code in the delivery address. The last line of a foreign address must only show the name of the country of destination.

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