There are 8 US Post Offices in Crawford County serving a total of 36,138 residents equating to 4,517 residents per post office. It's estimated that approximately 57,680 packages are handled across the 8 county post offices annually. Crawford County is a county located in the U.S. state of Missouri. At the 2010 Census, the population was 24,696. Its county seat is Steelville. The county was organized in 1829 and is named after U.S. Senator William H. Crawford of Georgia. The section of Sullivan which is located in Crawford County is included in the St. Louis, MO-IL Metropolitan Statistical Area. In 1990, the mean center of U.S. population was located in Crawford County.