There are 5 US Post Offices in Audubon County serving a total of 5,581 residents equating to 1,116 residents per post office. It's estimated that approximately 8,908 packages are handled across the 5 county post offices annually. Audubon County is a county located in the U.S. state of Iowa. As of the 2010 census, the population was 6,119, making it the third-least populous county in Iowa. Its county seat is Audubon. The county was named after John James Audubon, the noted naturalist and artist."