The Chicago metropolitan area, sometimes informally called Chicagoland, is the largest metropolitan statistical area in the U.S. state of Illinois and in the Midwest. Encompassing 10,286 square mi (28,120 km²), the metropolitan area contains the City of Chicago along with its surrounding suburbs, satellite cities, and hinterland, spanning 13 counties across northeast Illinois and northwest Indiana. The MSA had a 2020 census population of 9,618,502, and the combined statistical area, which spans 19 counties and extends into southeast Wisconsin, had a population of nearly 10 million. The Chicago area is the third-largest metropolitan area in the United States, the fourth-largest in North America, and the largest in the Great Lakes megalopolis. Its urban area is the 50th-largest in the world.