There are 4 US Post Offices in Rhea County serving a total of 33,670 residents equating to 8,418 residents per post office. It's estimated that approximately 53,741 packages are handled across the 4 county post offices annually. Rhea County (pronounced \"ray\") is a county located in the U.S. state of Tennessee. As of the 2010 census, the population was 31,809. Its county seat is Dayton. Rhea County comprises the Dayton, TN Micropolitan Statistical Area, which is also included in the Chattanooga-Cleveland-Dalton, TN-GA-AL Combined Statistical Area.