Chesterfield is a city in St. Louis County, Missouri, United States, and a second-ring western suburb of St. Louis. As of the 2010 census, the population was 47,484, making it the state's fourteenth-largest city. Chesterfield is the home of the headquarters of the Reinsurance Group of America (RGA), and as of 2013-14 has been experiencing a mass-construction boom.
Chesterfield is located about 25 miles (40 km) west of St. Louis, Missouri.
Portions of Chesterfield are located in the floodplain of the Missouri River, now known as Chesterfield Valley, formerly Gumbo Flats. This area was submerged during the Great Flood of 1993; higher levees built since then have led to extensive commercial development in the valley.Chesterfield Valley is the location of Spirit of St. Louis Airport, used for corporate aviation, as well as the longest outdoor strip mall in America.The remainder of Chesterfield is located on the bluffs above the floodplain, and includes residential and retail development. Chesterfield is also home to several mid- to high-rise buildings, the tallest being the Drury Plaza Hotel, which is 12 stories and 125 feet tall.