The Kansas City metropolitan area is a bi-state metropolitan area anchored by Kansas City, Missouri. Its 14 counties straddle the border between the U.S. states of Missouri and Kansas. With 8,472 square miles (21,940 km2) and a population of more than 2.2 million people, it is the second-largest metropolitan area centered in Missouri and is the largest metropolitan area in Kansas, though Wichita is the largest metropolitan area centered in Kansas. Alongside Kansas City, Missouri, these are the suburbs with populations above 100,000: Overland Park, Kansas; Kansas City, Kansas; Olathe, Kansas; Independence, Missouri; and Lee's Summit, Missouri.

Kansas City, Missouri is the largest city in the U.S. state of Missouri by population and area. Most of the city lies within Jackson County, with portions spilling into Clay, Platte, and Cass counties. It is the central city of the Kansas City metropolitan area, which straddles the Missouri–Kansas state line and has a population of 2,392,035. As of the 2020 census, the city had a population of 508,090, making it the 37th most-populous city in the United States, as well as the sixth-most populous city in the Midwest. Kansas City was founded in the 1830s as a port on the Missouri River at its confluence with the Kansas River from the west. On June 1, 1850, the town of Kansas was incorporated; shortly after came the establishment of the Kansas Territory. Confusion between the two ensued, and the name Kansas City was assigned to distinguish them soon after.