There are 6 US Post Offices in Madison County serving a total of 38,736 residents equating to 6,456 residents per post office. It's estimated that approximately 61,827 packages are handled across the 6 county post offices annually. Madison County is a county located in the U.S. state of Nebraska. As of the 2010 census, the population was 34,876. Its county seat is Madison. Madison County was named for James Madison, 4th President of the United States. Madison County is part of the Norfolk, NE Micropolitan Statistical Area. In the Nebraska license plate system, Madison County is represented by the prefix 7 (the county had the seventh-largest number of vehicles registered in the state when the license plate system was established in 1922)."