There are 13 US Post Offices in Lafayette County serving a total of 33,911 residents equating to 2,609 residents per post office. It's estimated that approximately 54,126 packages are handled across the 13 county post offices annually. Lafayette County is a county located in the western portion of the U.S. state of Missouri. As of the 2010 census, the population was 33,381. Its county seat is Lexington. The county was organized November 16, 1820 from Cooper County and originally named Lillard County for James Lillard of Tennessee, who served in the first state constitutional convention and first state legislature. It was renamed Lafayette County on February 16, 1825, in honor of Revolutionary War hero the Marquis de La Fayette, who was then visiting the United States. Lafayette County is part of the Kansas City, MO-KS Metropolitan Statistical Area."