There are 9 US Post Offices in Hardin County serving a total of 55,197 residents equating to 6,133 residents per post office. It's estimated that approximately 88,101 packages are handled across the 9 county post offices annually. Hardin County is a county located in the U.S. state of Texas, United States. As of the 2010 census, its population was 54,635. The county seat is Kountze. The county is named for the family of William Hardin from Liberty County, Texas. Hardin County is part of the Beaumont-Port Arthur, TX Metropolitan Statistical Area."