There are 8 US Post Offices in Poinsett County serving a total of 25,218 residents equating to 3,152 residents per post office. It's estimated that approximately 40,251 packages are handled across the 8 county post offices annually. Poinsett County is a county located in the U.S. state of Arkansas. As of the 2010 census, the population was 24,583. The county seat is Harrisburg. Poinsett County is included in the Jonesboro, AR Metropolitan Statistical Area."