There are 7 US Post Offices in Iosco County serving a total of 26,264 residents equating to 3,752 residents per post office. It's estimated that approximately 41,920 packages are handled across the 7 county post offices annually. Iosco County is a county located in the U.S. state of Michigan. As of the 2010 census, the population was 25,887. The county seat is Tawas City."