There are 4 US Post Offices in Chase County serving a total of 4,125 residents equating to 1,031 residents per post office. It's estimated that approximately 6,584 packages are handled across the 4 county post offices annually. Chase County is a county in the U.S. state of Nebraska. As of the 2010 census, the population was 3,966. Its county seat is Imperial. In the Nebraska license plate system, Chase County is represented by the prefix 72 (it had the 72nd-most vehicles registered in the state when the license plate system was established in 1922)."