There are 8 US Post Offices in Kings County serving a total of 151,702 residents equating to 18,963 residents per post office. It's estimated that approximately 242,133 packages are handled across the 8 county post offices annually. Kings County is a county located in the U.S. state of California. The population was 152,982 at the 2010 census. The California Department of Finance estimated that the county's population was 150,373 as of January 1, 2016. The county seat is Hanford. Kings County comprises the Hanford-Corcoran, CA Metropolitan Statistical Area, which is also included in the Visalia-Porterville-Hanford, CA Combined Statistical Area. It is located in the San Joaquin Valley, a rich agricultural region."