There are 12 US Post Offices in Florence County serving a total of 188,641 residents equating to 15,720 residents per post office. It's estimated that approximately 301,092 packages are handled across the 12 county post offices annually. Florence is a county located in the U.S. state of South Carolina. As of the 2010 census, its population was 136,885. Its county seat is Florence. Florence County is included in the Florence, SC Metropolitan Statistical Area. The county's population is about 60% urban."