There are 11 US Post Offices in Iowa County serving a total of 15,634 residents equating to 1,421 residents per post office. It's estimated that approximately 24,954 packages are handled across the 11 county post offices annually. Iowa County is a county located in the U.S. state of Iowa. As of the 2010 census, the population was 16,355. The county seat is Marengo. Iowa County is one of seven counties in the United States to share the same name as the state they are located in. The other six counties are Arkansas County, Hawaii County, Idaho County, New York County, Oklahoma County, and Utah County."