About 51111 - Sioux City, Iowa
Located in Iowa, the United States is home to the densely populated community of Sioux City, served by ZIP code 51111. It sits within Sioux City County.
Around 44,191 people live in the 51111 ZIP code area. That's noticeably above the average for a Iowa ZIP code, which sits near 22,608 people.
Median household income is about $69,000 (near the Iowa average).
Nearby communities in Iowa include Montour, Cresco, Davenport.