There are 7 US Post Offices in Rusk County serving a total of 12,904 residents equating to 1,843 residents per post office. It's estimated that approximately 20,596 packages are handled across the 7 county post offices annually. Rusk County is a county in the U.S. state of Wisconsin. As of the 2010 census, the population was 14,755. Its county seat is Ladysmith."