There are 21 US Post Offices in Washington County serving a total of 148,041 residents equating to 7,050 residents per post office. It's estimated that approximately 236,290 packages are handled across the 21 county post offices annually. Washington County, known locally as South County, is a county located in the U.S. state of Rhode Island. As of the 2010 census, the population was 126,979. Rhode Island counties, including Washington County, have no governmental functions other than as court administrative and sheriff corrections boundaries, which are part of the state government. Washington County is included in the Providence-Warwick, RI-MA Metropolitan Statistical Area, which is also included in the Boston-Worcester-Providence, MA-RI-NH-CT Combined Statistical Area."