There are 4 US Post Offices in Lee County serving a total of 18,499 residents equating to 4,625 residents per post office. It's estimated that approximately 29,526 packages are handled across the 4 county post offices annually. Lee County is a county located in the U.S. state of South Carolina. As of the 2010 census, its population was 19,220, making it the fifth-least populous county in South Carolina. Its county seat is Bishopville. The county is named for Confederate General Robert E. Lee. A previous incarnation of Lee County was established in 1898 and disestablished in the next year; the current Lee County was formed in 1902."