There are 6 US Post Offices in Butler County serving a total of 41,304 residents equating to 6,884 residents per post office. It's estimated that approximately 65,926 packages are handled across the 6 county post offices annually. Butler County is a county located in the southeast Ozark Foothills Region in the U.S. state of Missouri. As of the 2010 Census, the county's population was 42,794. The largest city and county seat is Poplar Bluff. The county was officially organized from Wayne County on February 27, 1849, and is named after former U.S. Representative William O. Butler (D-Kentucky), who was also an unsuccessful candidate for Vice President of the United States. The first meeting in the Butler County Courthouse was held on June 18, 1849. Butler County comprises the Poplar Bluff, MO Micropolitan Statistical Area."