There are 8 US Post Offices in Thayer County serving a total of 4,888 residents equating to 611 residents per post office. It's estimated that approximately 7,802 packages are handled across the 8 county post offices annually. Thayer County is a county in the U.S. state of Nebraska. As of the 2010 census, the population was 5,228. Its county seat is Hebron. The county was created in 1856 and originally named Jefferson County. It was organized in 1870-1871 and renamed for the General and Governor John Milton Thayer. In the Nebraska license plate system, Thayer County is represented by the prefix 32 (it had the thirty-second-largest number of vehicles registered in the state when the license plate system was established in 1922)."