There are 7 US Post Offices in Hill County serving a total of 17,355 residents equating to 2,479 residents per post office. It's estimated that approximately 27,701 packages are handled across the 7 county post offices annually. Hill County is a county located in the U.S. state of Montana. As of the 2010 census, the population was 16,096. Its county seat is Havre. It is south from the Canadian borders of Alberta and Saskatchewan."