Missouri Counties

Franklin County, Mo.
Union is the county seat of Franklin County, which has an estimated population of 99,773. The Missouri River defines the northern border; Interstate 44 crosses the county east to west. Manufacturing is the dominant industry, primarily in the city of Washington. Small farms and wineries also contribute to the economy.

Jefferson County, Mo.
Jefferson County, bordered on the east by the Mississippi River, has experienced rapid growth recently to 215,797 due to migration from St. Louis City and County. Manufacturing is the major industry. Interstate 55 connects the county to Memphis, the City of St. Louis, and Chicago.

Lincoln County, Mo.
Lincoln County, whose county seat is Troy, is north of Warren and St. Charles Counties with the Mississippi River to the east. Manufacturing and service industries are major employers. The county is one of the fastest growing in the country with a population of 48,855, which increased by more than 17.4% from 2000 to 2004.

St. Charles County, Mo.
St. Charles County, with a population of 337,572, has been one of the fastest-growing counties in the country for decades, with 55 percent growth in the 1980s, 33 percent in the 1990s, and another 13 percent between 2000 and 2004. The county features a cross-section of industry, as well as extensive retail and some agriculture. With the Missouri River on the south and the Mississippi on the north and east, the county is bisected east to west by Interstate 70. St. Charles County has two small airports and two ferries that cross the Mississippi River. The City of St. Charles is the county seat.

City of St. Louis, Mo.
Home to an estimated 352,572 people within 61.9 square miles, the City of St. Louis is the most densely populated and industrial county in the metropolitan area. Manufacturing and corporate headquarters have a strong presence. St. Louis County lies west with the Mississippi River on the east. Interstates 55, 70, 64, and 44 all pass through the city.

St. Louis County, Mo.
With 1,003,389 residents, St. Louis County is the most populous of the metropolitan-area counties. There is still some agriculture along the Missouri River in the north, but overall the area is thoroughly suburban with many corporate offices and service businesses. Interstates 70, 44, 55, and 64 make travel expedient. Clayton, the county seat, is often called the St. Louis area’s “second downtown”.

Warren County, Mo.
Warren County, population 29,298, is primarily agricultural. The Missouri River forms the southern border; Interstate 70 crosses the county east to west. Warrenton is the county seat.

Washington County, Mo.
Washington County is primarily agricultural. This southernmost county in the metropolitan area is home to 24,119, with the county seat in Potosi.