There are 14 US Post Offices in Hill County serving a total of 34,673 residents equating to 2,477 residents per post office. It's estimated that approximately 55,342 packages are handled across the 14 county post offices annually. Hill County is a county located in the U.S. state of Texas. As of the 2010 census, the population was 35,089. Its county seat is Hillsboro. The county is named for George Washington Hill, secretary of war and secretary of the navy under the Republic of Texas. Hill County is part of Central Texas, though not included in Texas Hill Country."