There are 6 US Post Offices in Sarpy County serving a total of 84,446 residents equating to 14,074 residents per post office. It's estimated that approximately 134,785 packages are handled across the 6 county post offices annually. Sarpy County is a county in the U.S. state of Nebraska. As of the 2010 census, the population was 158,840, making it the third most populous county in Nebraska. Its county seat is Papillion. Sarpy County is part of the Omaha-Council Bluffs, NE-IA Metropolitan Statistical Area. In the Nebraska license plate system, Sarpy County was represented by the prefix \"59\" (it had the fifty-ninth largest number of vehicles registered in the county when the license plate system was established in 1922). Many license plates issued in Sarpy County featured the stacked format of the 59 code. The county, just south of Omaha, had grown significantly in population in the decades following 1922 and therefore required five characters rather than the four allowed by a standard double-digit county code. In 2002, the state discontinued the 1922 system in Sarpy as well as Douglas and Lancaster counties."