There are 6 US Post Offices in Putnam County serving a total of 79,590 residents equating to 13,265 residents per post office. It's estimated that approximately 127,035 packages are handled across the 6 county post offices annually. Putnam County is a county located in the U.S. state of Tennessee. As of the 2010 census, the population was 72,321. Its county seat is Cookeville. Putnam County is part of the Cookeville, TN Micropolitan Statistical Area."