There are 12 US Post Offices in Gibson County serving a total of 55,197 residents equating to 4,600 residents per post office. It's estimated that approximately 88,101 packages are handled across the 12 county post offices annually. Gibson County is a county located in the U.S. state of Tennessee. As of the 2010 census, the population was 49,683. Its county seat is Trenton. The county was formed in 1823 and named for John H. Gibson, a soldier of the Natchez Expedition and the Creek War."