There are 14 US Post Offices in Benton County serving a total of 24,904 residents equating to 1,779 residents per post office. It's estimated that approximately 39,750 packages are handled across the 14 county post offices annually. Benton County is a county located in the U.S. state of Iowa. As of the 2010 census, the population was 26,076. Its county seat is Vinton. The county is named for Thomas Hart Benton, a U.S. Senator from Missouri. Benton County is included in the Cedar Rapids, IA Metropolitan Statistical Area.