There are 11 US Post Offices in Clay County serving a total of 16,199 residents equating to 1,473 residents per post office. It's estimated that approximately 25,855 packages are handled across the 11 county post offices annually. Clay County is a county located in the U.S. state of Arkansas. As of the 2010 census, the population was 16,083. The county has two county seats, Corning and Piggott. It is a dry county, in which the sale of alcoholic beverages is restricted or prohibited."