There are 6 US Post Offices in Highlands County serving a total of 90,516 residents equating to 15,086 residents per post office. It's estimated that approximately 144,474 packages are handled across the 6 county post offices annually. Highlands County is a county located in the U.S. state of Florida. As of the 2010 census, the population was 98,786. Its county seat is Sebring. Highlands County comprises the Sebring, FL Metropolitan Statistical Area."