The Chicago metropolitan area, also referred to as Chicagoland, is the largest
metropolitan statistical area in the
U.S. state
In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its so ...
of
Illinois
Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...
, and the
Midwest
The Midwestern United States (also referred to as the Midwest, the Heartland or the American Midwest) is one of the four census regions defined by the United States Census Bureau. It occupies the northern central part of the United States. It ...
, containing the
City of Chicago
Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of Unite ...
along with its surrounding suburbs and satellite cities. Encompassing 10,286 square mi (28,120 km
2), the metropolitan area includes the city of Chicago, its
suburbs
A suburb (more broadly suburban area) is an area within a metropolitan area. They are oftentimes where most of a metropolitan areas jobs are located with some being predominantly residential. They can either be denser or less densely populated ...
and
hinterland
Hinterland is a German word meaning the 'land behind' a city, a port, or similar. Its use in English was first documented by the geographer George Chisholm in his ''Handbook of Commercial Geography'' (1888). Originally the term was associated wi ...
, that span 13
counties
A county () is a geographic region of a country used for administrative or other purposesL. Brookes (ed.) '' Chambers Dictionary''. Edinburgh: Chambers Harrap Publishers Ltd, 2005. in some nations. The term is derived from the Old French denoti ...
across northeast
Illinois
Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...
and northwest
Indiana
Indiana ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Michigan to the northwest, Michigan to the north and northeast, Ohio to the east, the Ohio River and Kentucky to the s ...
. The MSA had a 2020 census population of 9,618,502 and the combined statistical area, which spans 19 counties and additionally extends into southeast
Wisconsin
Wisconsin ( ) is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest of the United States. It borders Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michig ...
, had a population of nearly 10 million people.
The Chicago area is the
third-largest metropolitan area in the United States and the fourth-largest metropolitan area in
North America
North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...
(after Mexico City, New York City, and Los Angeles), and the largest in the
Great Lakes megalopolis. Its urban area is one of the
40 largest in the world.
According to the
2020 census, the metropolitan's population is approaching the 10 million mark. The metropolitan area has seen a substantial increase of
Latin American
Latin Americans (; ) are the citizenship, citizens of Latin American countries (or people with cultural, ancestral or national origins in Latin America).
Latin American countries and their Latin American diaspora, diasporas are Metroethnicity, ...
residents on top of its already large Latino population, and the
Asian American
Asian Americans are Americans with ancestry from the continent of Asia (including naturalized Americans who are immigrants from specific regions in Asia and descendants of those immigrants).
Although this term had historically been used fo ...
population also increased according to the 2020 Census. The metro area has a large number of
White
White is the lightest color and is achromatic (having no chroma). It is the color of objects such as snow, chalk, and milk, and is the opposite of black. White objects fully (or almost fully) reflect and scatter all the visible wa ...
,
Black
Black is a color that results from the absence or complete absorption of visible light. It is an achromatic color, without chroma, like white and grey. It is often used symbolically or figuratively to represent darkness.Eva Heller, ''P ...
,
Latino,
Asian, and
Arab American
Arab Americans ( or ) are Americans who trace ancestry to any of the various waves of immigrants from the Arabic-speaking countries. In the United States census, Arabs are racially classified as White Americans which is defined as "A person ha ...
residents, and also has
Native American residents in the region, making the Chicago metropolitan area population truly diverse. The Chicago metropolitan area represents about 3 percent of the entire US population.
Chicagoland has one of the world's largest and most diversified economies. With more than six million full and part-time employees, the Chicago metropolitan area is a key factor of the Illinois economy, as the state has an annual GDP of over $1 trillion. The Chicago metropolitan area generated an annual
gross regional product
Gross regional domestic product (GRDP), gross domestic product of region (GDPR), or gross state product (GSP) is a statistic that measures the size of a region's economy. It is the aggregate of gross value added (GVA) of all resident producer unit ...
(GRP) of approximately $700 billion in 2018. The region is home to more than 400 major corporate headquarters, including 31 in the
''Fortune'' 500 such as McDonald's, United, and Blue Cross Blue Shield. With many companies moving to Chicagoland, and many current companies expanding, the area ranked as the nation's top metropolitan area for corporation relocations and expansions for nine consecutive years, the most consecutive years for any region in the country.
The Chicago area is home to a number of the nation's leading
research universities
A research university or a research-intensive university is a university that is committed to research as a central part of its mission. They are "the key sites of knowledge production", along with "intergenerational knowledge transfer and the ...
including the
University of Chicago
The University of Chicago (UChicago, Chicago, or UChi) is a Private university, private research university in Chicago, Illinois, United States. Its main campus is in the Hyde Park, Chicago, Hyde Park neighborhood on Chicago's South Side, Chic ...
,
Northwestern University
Northwestern University (NU) is a Private university, private research university in Evanston, Illinois, United States. Established in 1851 to serve the historic Northwest Territory, it is the oldest University charter, chartered university in ...
, the
University of Illinois at Chicago
The University of Illinois Chicago (UIC) is a public research university in Chicago, Illinois, United States. Its campus is in the Near West Side community area, adjacent to the Chicago Loop. The second campus established under the Universi ...
,
DePaul University
DePaul University is a private university, private Catholic higher education, Catholic research university in Chicago, Illinois, United States. Founded by the Congregation of the Mission, Vincentians in 1898, the university takes its name from ...
,
Loyola University, and the
Illinois Institute of Technology
The Illinois Institute of Technology, commonly referred to as Illinois Tech and IIT, is a Private university, private research university in Chicago, Illinois, United States. Tracing its history to 1890, the present name was adopted upon the m ...
(IIT). The University of Chicago and Northwestern University are consistently ranked as two of the best universities in the world.
There are many transportation options around the region. Chicagoland has three separate rail networks; the
Chicago Transit Authority
The Chicago Transit Authority (CTA) is the operator of public transport, mass transit in Chicago, Illinois, United States, and some of its suburbs, including the trains of the Chicago "L" and List of Chicago Transit Authority bus routes, CTA bu ...
(CTA),
Metra
Metra is the primary commuter rail system in the Chicago metropolitan area serving the city of Chicago and its surrounding suburbs via the Union Pacific Railroad, BNSF Railway, and other railroads. The system operates 243 train station, stati ...
, and the
South Shore Line. The CTA operates elevated and subway lines that run primarily throughout the city,
Downtown Chicago, and into some suburbs. The CTA operates some of its rail lines 24 hours a day, every day of the year, nonstop service, making Chicago, New York City, and Copenhagen the only three cities in the world to offer some 24 hour rail service running nonstop, everyday throughout their city limits. The Metra
commuter rail
Commuter rail or suburban rail is a Passenger train, passenger rail service that primarily operates within a metropolitan area, connecting Commuting, commuters to a Central business district, central city from adjacent suburbs or commuter town ...
network runs numerous lines between Downtown Chicago and suburban/satellite cities, with one line stretching to
Kenosha, Wisconsin
Kenosha () is a city in Kenosha County, Wisconsin, United States, and its county seat. It is the List of cities in Wisconsin, fourth-most populous city in Wisconsin, with a population of 99,986 at the 2020 United States census, 2020 census. S ...
, which is part of the Chicago metropolitan area. The
interurban
The interurban (or radial railway in Canada) is a type of electric railway, with tram-like electric self-propelled railcars which run within and between cities or towns. The term "interurban" is usually used in North America, with other terms u ...
South Shore Line runs between Downtown Chicago and the northwest Indiana portion of the metropolitan area. In addition,
Amtrak
The National Railroad Passenger Corporation, Trade name, doing business as Amtrak (; ), is the national Passenger train, passenger railroad company of the United States. It operates intercity rail service in 46 of the 48 contiguous United Stat ...
operates
Union Station
A union station, union terminal, joint station, or joint-use station is a railway station at which the tracks and facilities are shared by two or more separate railway company, railway companies, allowing passengers to connect conveniently bet ...
in Downtown Chicago as one of its largest rail hubs, with numerous lines radiating to and from the station.
CTA bus routes serve the city proper, with some service into the suburbs.
Pace bus routes serve the suburbs, with some service into the city. In addition, numerous CTA bus routes operate 24 hours a day, nonstop.
Definitions
Chicago Metropolitan statistical area

The Chicago
metropolitan statistical area (MSA) was originally designated by the United States Census Bureau in 1950. It comprised the
Illinois
Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...
counties of Cook, DuPage, Kane, Lake and Will, along with Lake County in
Indiana
Indiana ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Michigan to the northwest, Michigan to the north and northeast, Ohio to the east, the Ohio River and Kentucky to the s ...
. As surrounding counties saw an increase in their population densities and the number of their residents employed within Cook County, they met Census criteria to be added to the MSA. The Chicago MSA, now defined by the U.S.
Office of Management and Budget
The Office of Management and Budget (OMB) is the largest office within the Executive Office of the President of the United States (EOP). The office's most prominent function is to produce the president's budget, while it also examines agency pro ...
(OMB) as the Chicago–Naperville–Elgin, IL–IN–WI Metropolitan Statistical Area, is the third-largest MSA by population in the United States. The 2022 census estimate for the population of the MSA was 9,441,957.
The Chicago MSA is further subdivided into four metropolitan divisions. A breakdown of the county constituents and 2021 estimated populations of the four metropolitan divisions of the MSA are as follows:
Chicago–Naperville–Elgin, IL–IN–WI Metropolitan Statistical Area (9,509,934)
* ''Chicago–Naperville–Schaumburg, IL Metropolitan Division'' (7,159,394)
**
Cook County, Illinois
Cook County is the List of counties in Illinois, most populous county in the U.S. state of Illinois and the List of the most populous counties in the United States, second-most-populous county in the United States, after Los Angeles County, C ...
(5,173,146)
**
DuPage County, Illinois
DuPage County ( ) is a County (United States), county in the U.S. state of Illinois, and one of the collar counties of the Chicago metropolitan area. As of the 2020 United States census, 2020 census, the population was 932,877, making it List of ...
(924,885)
**
Grundy County, Illinois
Grundy County is a county in the U.S. state of Illinois. According to the 2020 census, it has a population of 52,533. Its county seat is Morris.
Grundy County is part of the Chicago metropolitan area.
In 2010, the center of population of I ...
(52,989)
**
McHenry County, Illinois
McHenry County is a County (United States), county located in the U.S. state of Illinois. According to the 2020 United States census, 2020 Census, it had a population of 310,229, making it the sixth-most populous county in Illinois. Its count ...
(311,122)
**
Will County, Illinois
Will County is a county in the northeastern part of the state of Illinois. According to the 2020 census, it had a population of 696,355, an increase of 2.8% from 677,560 in 2010, making it Illinois's fourth-most populous county. The county sea ...
(697,252)
* ''Elgin, IL Metropolitan Division'' (750,869)
**
DeKalb County, Illinois (100,414)
**
Kane County, Illinois
Kane County is a County (United States), county in the U.S. state of Illinois. According to the 2020 United States census, 2020 census, it has a population of 516,522, making it the fifth-most populous county in Illinois. Its county seat is Gen ...
(515,588)
**
Kendall County, Illinois
Kendall County is a county in the U.S. state of Illinois, within the Chicago metropolitan area. According to the 2020 census, it has a population of 131,869. Its county seat is Yorkville, and its most populous municipality is Oswego.
Kend ...
(134,867)
* ''Lake County, IL Metropolitan Division'' (711,239)
**
Lake County, Illinois
Lake County is a County (United States), county located in the northeastern corner of the U.S. state of Illinois, along the shores of Lake Michigan. As of the 2020 United States census, 2020 census, it has a population of 714,342, making it th ...
(711,239)
* ''Lake County–Porter County–Jasper County, IN Metropolitan Division'' (719,700)
**
Jasper County, Indiana
Jasper County is a county (United States), county located in the U.S. state of Indiana. As of 2020, the population was 32,918. The county seat is Rensselaer, Indiana, Rensselaer. Jasper County is included in the Chicago-Naperville, Illinois, ...
(33,091)
**
Lake County, Indiana
Lake County is a county (United States), county located in the U.S. state of Indiana. In 2020, its population was 498,700, making it Indiana's List of counties in Indiana, second-most populous county. The county seat is Crown Point, Indiana, C ...
(498,558)
**
Newton County, Indiana
Newton County is a county located near the northwestern corner of the U.S. state of Indiana. As of 2020, the population was 13,830. This county is part of Northwest Indiana as well as the Chicago metropolitan area. The county seat is Kentl ...
(13,808)
**
Porter County, Indiana
Porter County is a county (United States), county in the U.S. state of Indiana. As of 2020, the population was 173,215, making it the 10th most populous county in Indiana. The county seat is Valparaiso, Indiana, Valparaiso. The county is part of ...
(174,243)
Combined statistical area
The OMB also defines a slightly larger region as a
combined statistical area (CSA). The Chicago–Naperville, IL–IN–WI Combined Statistical Area combines the following
core-based statistical areas, listed with their 2021 estimated populations. The combined statistical area as a whole had a population of 9,806,184 as of 2022.
* ''Chicago–Naperville–Elgin, IL–IN–WI metropolitan statistical area'' (9,509,934)
* ''Kankakee, IL metropolitan statistical area'' (106,601)
**
Kankakee County, Illinois
Kankakee County is a county located in the U.S. state of Illinois. According to the 2020 census, it has a population of 107,502. Its county seat is Kankakee. Kankakee County comprises the Kankakee, IL Metropolitan Statistical Area.
History ...
(106,601)
* ''Michigan City–La Porte, IN metropolitan statistical area'' (112,390)
**
LaPorte County, Indiana (112,390)
* ''Ottawa, IL micropolitan statistical area'' (147,414)
**
Bureau County, Illinois
Bureau County is a county located in the U.S. state of Illinois. As of the 2020 United States census, the population was 33,244. Its county seat is Princeton. Bureau County is part of the Ottawa, IL Micropolitan Statistical Area, and the He ...
(32,883)
**
LaSalle County, Illinois
LaSalle County is a county located within the Fox Valley and Illinois River Valley regions of the U.S. state of Illinois. As of the 2020 Census, it had a population of 109,658. Its county seat and largest city is Ottawa. LaSalle County is ...
(108,965)
**
Putnam County, Illinois (5,566)
United Nations' Chicago urban agglomeration
The Chicago
urban agglomeration
An urban area is a human settlement with a high population density and an infrastructure of built environment. Urban areas originate through urbanization, and researchers categorize them as cities, towns, conurbations or suburbs. In urbani ...
, according to the
United Nations
The United Nations (UN) is the Earth, global intergovernmental organization established by the signing of the Charter of the United Nations, UN Charter on 26 June 1945 with the stated purpose of maintaining international peace and internationa ...
''World Urbanization Prospects'' report (2023 revision), lists a population of 8,937,000. The term "urban agglomeration" refers to the population contained within the contours of a contiguous territory inhabited at
urban density
Urban density is a concept used in urban planning, urban studies, and related fields to describe the intensity of people, jobs, housing units, total floor area of buildings, or some other measure of human occupation, activity, and development acro ...
levels. It usually incorporates the population in a city, plus that in the contiguous urban, or built-up area.
Chicagoland

Chicagoland is an informal name for the Chicago metropolitan area. The term ''Chicagoland'' has no official definition, and the region is often considered to include areas beyond the corresponding MSA, as well as portions of the greater CSA.
Colonel Robert R. McCormick, editor and publisher of the ''
Chicago Tribune
The ''Chicago Tribune'' is an American daily newspaper based in Chicago, Illinois, United States. Founded in 1847, it was formerly self-styled as the "World's Greatest Newspaper", a slogan from which its once integrated WGN (AM), WGN radio and ...
'', usually gets credit for placing the term in common use.
McCormick's conception of Chicagoland stretched all the way to nearby parts of four states (Indiana,
Wisconsin
Wisconsin ( ) is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest of the United States. It borders Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michig ...
,
Michigan
Michigan ( ) is a peninsular U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest, Upper Midwestern United States. It shares water and land boundaries with Minnesota to the northwest, Wisconsin to the west, ...
, and
Iowa
Iowa ( ) is a U.S. state, state in the upper Midwestern United States, Midwestern region of the United States. It borders the Mississippi River to the east and the Missouri River and Big Sioux River to the west; Wisconsin to the northeast, Ill ...
).
The first usage was in the ''Tribunes July 27, 1926, front page headline, "Chicagoland's Shrines: A Tour of Discoveries", for an article by reporter
James O'Donnell Bennett. He stated that Chicagoland comprised everything in a radius in every direction and reported on many different places in the area. The ''Tribune'' was the dominant newspaper in a vast area stretching to the west of the city, and that
hinterland
Hinterland is a German word meaning the 'land behind' a city, a port, or similar. Its use in English was first documented by the geographer George Chisholm in his ''Handbook of Commercial Geography'' (1888). Originally the term was associated wi ...
was closely tied to the metropolis by rail lines and commercial links.
Today, the ''Chicago Tribunes usage includes the city of Chicago, the rest of
Cook County, eight nearby Illinois counties (Lake,
McHenry,
DuPage,
Kane,
Kendall,
Grundy,
Will
Will may refer to:
Common meanings
* Will and testament, instructions for the disposition of one's property after death
* Will (philosophy), or willpower
* Will (sociology)
* Will, volition (psychology)
* Will, a modal verb - see Shall and will
...
, and
Kankakee), and the two Indiana counties of Lake and
Porter. Illinois Department of Tourism literature uses ''Chicagoland'' for suburbs in Cook, Lake, DuPage, Kane, and Will counties, treating the city separately. The
Chicagoland Chamber of Commerce defines it as all of Cook, DuPage, Kane, Lake, McHenry, and Will counties.
In addition, company marketing programs such as Construction Data Company's "Chicago and Vicinity" region and the
Chicago Automobile Trade Association's ''"Chicagoland and Northwest Indiana"'' advertising campaign are directed at the MSA itself, as well as LaSalle,
Winnebago (
Rockford),
Boone, and
Ogle counties in Illinois, in addition to
Jasper
Jasper, an aggregate of microgranular quartz and/or cryptocrystalline chalcedony and other mineral phases, is an opaque, impure variety of silica, usually red, yellow, brown or green in color; and rarely blue. The common red color is due to ...
,
Newton, and
La Porte counties in Indiana and
Kenosha,
Racine, and
Walworth
Walworth ( ) is a district of South London, England, within the London Borough of Southwark. It adjoins Camberwell to the south and Elephant and Castle to the north, and is south-east of Charing Cross.
Major streets in Walworth include the ...
counties in Wisconsin, and even as far northeast as
Berrien County, Michigan. The region is part of the
Great Lakes Megalopolis, containing an estimated 54 million people.
Collar counties
The term "
collar counties" is a
colloquialism
Colloquialism (also called ''colloquial language'', ''colloquial speech'', ''everyday language'', or ''general parlance'') is the linguistic style used for casual and informal communication. It is the most common form of speech in conversation amo ...
for the five counties (DuPage, Kane, Lake,
McHenry, and Will) of Illinois that border Chicago's Cook County. After Cook County, they are also the next five most populous counties in the state. According to the ''Encyclopedia of Chicago'', there is no specifically known origin of the phrase, but it has been commonly used among policy makers, urban planners, and in the media. However, it also notes that as growth has spread beyond these counties, it may have lost some of its usefulness.
Chicago Metropolitan Agency for Planning
Chicago Metropolitan Agency for Planning (CMAP) is an Illinois state agency responsible for transportation infrastructure, land use, and long-term economic development planning for the areas under its jurisdiction within Illinois. The planning area has a population of over 8 million, which includes the following locations in Illinois:
*
Cook County
*
DuPage County
*
Kane County
*
Kendall County
*
Lake County
*
McHenry County
*
Will County
Geography and environment
The city of Chicago lies in the Chicago Plain, a flat and broad area characterized by little topographical relief. The few low hills are sand ridges. North of the Chicago Plain, steep bluffs and ravines run alongside Lake Michigan.
Along the southern shore of the Chicago Plain, sand dunes run alongside the lake. The tallest dunes reach up to near and are found in
Indiana Dunes National Park
Indiana Dunes National Park is a List of national parks of the United States, national park of the United States located in northwestern Indiana managed by the National Park Service. It was authorized by Congress in 1966 as the Indiana Dunes Na ...
. Surrounding the low plain are bands of
moraine
A moraine is any accumulation of unconsolidated debris (regolith and Rock (geology), rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a gla ...
s in the south and west suburbs. These areas are higher and hillier than the Chicago Plain. A
continental divide, separating the
Mississippi River
The Mississippi River is the main stem, primary river of the largest drainage basin in the United States. It is the second-longest river in the United States, behind only the Missouri River, Missouri. From its traditional source of Lake Ita ...
watershed from that of the
Great Lakes
The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes spanning the Canada–United States border. The five lakes are Lake Superior, Superior, Lake Michigan, Michigan, Lake Huron, H ...
and
Saint Lawrence River
The St. Lawrence River (, ) is a large international river in the middle latitudes of North America connecting the Great Lakes to the North Atlantic Ocean. Its waters flow in a northeasterly direction from Lake Ontario to the Gulf of St. Lawrenc ...
, runs through the Chicago area.
A 2012 survey of the urban trees and forests in the seven county Illinois section of the Chicago area found that 21% of the land is covered by the tree and shrub canopy, made up of about 157,142,000 trees. The five most common tree species are
buckthorn
''Rhamnus'' is a genus of about 140 accepted species of shrubs or small trees, commonly known as buckthorns, in the family Rhamnaceae. Its species range from tall (rarely to ) and are native mainly in east Asia and North America, but found thr ...
,
green ash
Green is the color between cyan and yellow on the visible spectrum. It is evoked by light which has a dominant wavelength of roughly 495570 nm. In subtractive color systems, used in painting and color printing, it is created by a combi ...
,
boxelder,
black cherry, and
American elm. These resources perform important functions in carbon storage, water recycling, and energy saving.
Demographics
Race and ethnicity
As of 2022, the metropolitan area had a population of 9,442,159. The population density was 1,312.3 per square mile.
The racial makeup was 50.1% Non-Hispanic White, 23.4% were Hispanic, 15.5% were Non-Hispanic African Americans, 7.2% were Asian, 0.1% were Non-Hispanic Native American, 0.4% identified as “some other race,” and 3.2% were non-Hispanic multiracial.
Ancestry
According to 2023 estimates from the
American Community Survey
The American Community Survey (ACS) is an annual demographics survey program conducted by the United States Census Bureau. It regularly gathers information previously contained only in the long form of the United States census, decennial census ...
, the largest ancestries in the Chicago metro area were
Mexican (18.3%),
African (17.7%),
German (12.6%),
Irish (9.9%),
Polish (7.8%),
Italian (6.2%),
English (4.8%),
Indian (2.7%),
Puerto Rican (2.2%),
Filipino (1.7%),
Swedish (1.5%), and
Chinese (1.5%).
Urban growth
The suburbs, surrounded by easily annexed flat ground, have been expanding at a tremendous rate since the early 1960s. Aurora, Elgin, Joliet, and Naperville are noteworthy for being four of the few
boomburb
A boomburb is a large, rapidly-growing city that remains essentially suburban in character, even as it reaches populations more typical of urban core cities. It describes a relatively recent phenomenon in a United States context. The neologism wa ...
s outside the
Sun Belt
The Sun Belt is a region of the United States generally considered stretching across the Southeast and Southwest. Another rough definition of the region is the area south of the Parallel 36°30′ north. Several climates can be found in the re ...
,
West Coast and
Mountain States
The Mountain states (also known as the Mountain West or the Interior West) form one of the nine geographic divisions of the United States that are officially recognized by the United States Census Bureau. It is a subregion of the Western Un ...
regions, and
exurban Kendall County ranked as the fastest-growing county (among counties with a population greater than 10,000) in the United States between the years 2000 and 2007.
Income
Settlement patterns in the Chicago metropolitan area tend to follow those in the city proper: the northern and northwestern suburbs are generally affluent and
upper-middle class, while the southern suburbs (sometimes known as
Chicago Southland) have somewhat lower median incomes and a cost of living, with the exception being the southwest suburbs which contain many upper-middle class areas. Another exception to this is the
West Side, which has a somewhat lower median income, but the western suburbs contain many affluent and upper-middle class areas. According to the 2000 Census, DuPage County as a whole had the highest median household income of any county in the
Midwestern United States
The Midwestern United States (also referred to as the Midwest, the Heartland or the American Midwest) is one of the four census regions defined by the United States Census Bureau. It occupies the northern central part of the United States. It ...
, although there are individual cities and towns in other surrounding counties in the metro that have even higher median incomes.
According to 2022 estimates from the U.S. Census, poverty rates of the largest counties from least poverty to most are as follows: McHenry 4.0%, Dupage 6.7%, Will 6.9%, Kane 7.8%, Lake 8.0%, and Cook 13.6%. However, Cook County, which contains luxury high rises and expensive houses in sections of the city and expensive houses along the waterfront in the
North Shore area, would also have the highest percentage of expensive homes in the region.
In an in-depth historical analysis, Keating (2004, 2005) examined the origins of 233 settlements that by 1900 had become suburbs or city neighborhoods of the Chicago metropolitan area. The settlements began as farm centers (41%), industrial towns (30%), residential railroad suburbs (15%), and recreational/institutional centers (13%). Although relations between the different settlement types were at times contentious, there also was cooperation in such undertakings as the construction of high schools.
Population
As the Chicago metropolitan area has grown, more counties have been partly or totally assimilated with the taking of each decennial census.
Counties highlighted in gray were not included in the MSA for that census.
The CSA totals in blue are the totals of all the counties listed above, regardless of whether they were included in the Chicago Combined Statistical Area at the time.
Principal municipalities
Over 1,000,000 population
*
Chicago
Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of Unite ...
(2,746,388)
Over 100,000 population
*
Aurora, Illinois
Aurora is a city in northeastern Illinois, United States. It is located along the Fox River (Illinois River tributary), Fox River west of Chicago. It is the List of municipalities in Illinois, second-most populous city in Illinois, with a popul ...
(180,542)
*
Joliet, Illinois
Joliet ( ) is a city in Will County, Illinois, Will and Kendall County, Illinois, Kendall counties in the U.S. state of Illinois, located southwest of Chicago. It is the county seat of Will County, Illinois, Will County. It had a population of ...
(150,362)
*
Naperville, Illinois
Naperville ( ) is a city in DuPage County, Illinois, DuPage and Will County, Illinois, Will counties in the U.S. state of Illinois. It is a southwestern suburb of Chicago located west of the city on the DuPage River. As of the 2020 United State ...
(149,540)
*
Elgin, Illinois
Elgin ( ) is a city in Cook County, Illinois, Cook and Kane County, Illinois, Kane counties in the U.S. state of Illinois. It is located northwest of Chicago along the Fox River (Illinois River tributary), Fox River. As of the 2020 United Stat ...
(114,797)
Over 50,000 population
*
Kenosha, Wisconsin
Kenosha () is a city in Kenosha County, Wisconsin, United States, and its county seat. It is the List of cities in Wisconsin, fourth-most populous city in Wisconsin, with a population of 99,986 at the 2020 United States census, 2020 census. S ...
(99,986)
*
Waukegan, Illinois
Waukegan ( ) is a city in Lake County, Illinois, United States, and its county seat. Located north of Chicago, Waukegan is a satellite city within the greater Chicago metropolitan area.
As of the 2020 census, its population was 89,321, makin ...
(89,321)
*
Cicero, Illinois
Cicero is a town in Cook County, Illinois, United States, and a suburb of Chicago. As of the 2020 census, the population was 85,268, making it the 11th-most populous municipality in Illinois. The town is named after Marcus Tullius Cicero, a R ...
(85,268)
*
Schaumburg, Illinois
Schaumburg ( ) is a village in Cook County, Illinois, Cook and DuPage County, Illinois, DuPage counties in the U.S. state of Illinois. Per the 2020 United States census, 2020 census, the population was 78,723, making Schaumburg the most populou ...
(78,723)
*
Evanston, Illinois
Evanston is a city in Cook County, Illinois, United States, situated on the North Shore (Chicago), North Shore along Lake Michigan. A suburb of Chicago, Evanston is north of Chicago Loop, downtown Chicago, bordered by Chicago to the south, Skok ...
(78,110)
*
Hammond, Indiana
Hammond ( ) is a city in Lake County, Indiana, United States. Located along Lake Michigan, it is part of the Chicago metropolitan area and the only city in Indiana to border Chicago. As of the 2020 United States census, 2020 census, it is the Li ...
(77,879)
*
Arlington Heights, Illinois
Arlington Heights is a village in Cook County, Illinois, Cook County Illinois, United States. A northwestern Chicago metropolitan area, suburb of Chicago, it lies about northwest of the city's downtown. As of the 2020 United States census, 2020 ...
(77,676)
*
Bolingbrook, Illinois (73,922)
*
Gary, Indiana
Gary ( ) is a city in Lake County, Indiana, United States. The population was 69,093 at the 2020 United States census, 2020 census, making it Indiana's List of municipalities in Indiana, eleventh-most populous city. The city has been historical ...
(69,093)
*
Palatine, Illinois (67,908)
*
Skokie, Illinois
Skokie (; formerly Niles Center) is a Village (United States), village in Cook County, Illinois, United States. According to the 2020 United States census, 2020 census, its population was 67,824. Skokie lies approximately north of Chicago's dow ...
(67,824)
*
Des Plaines, Illinois
Des Plaines () is a city in Cook County, Illinois, United States. Per the 2020 United States census, 2020 census, the population was 60,675. The city is a suburb of Chicago and is located just north of O'Hare International Airport. It is situat ...
(60,675)
*
Orland Park, Illinois (58,703)
*
Oak Lawn, Illinois (58,362)
*
Berwyn, Illinois
Berwyn () is a suburban city in Cook County, Illinois, United States, Coterminous municipality, coterminous with Berwyn Township, Illinois, Berwyn Township, which was formed in 1908 after breaking off from Cicero Township, Cook County, Illinois, ...
(57,250)
*
Mount Prospect, Illinois (56,852)
*
Tinley Park, Illinois (55,971)
*
Oak Park, Illinois
Oak Park is a village in Cook County, Illinois, United States, adjacent to Chicago. It is the List of municipalities in Illinois, 26th-most populous municipality in Illinois, with a population of 54,318 as of the 2020 census. Oak Park was first se ...
(54,583)
*
Wheaton, Illinois (53,970)
*
Downers Grove, Illinois
Downers Grove is a village in DuPage County, Illinois, United States. It was founded in 1832 by Pierce Downer, whose surname serves as the eponym for the village. Per the 2020 United States census, 2020 census, the population of the village was ...
(50,247)
Urban areas within
Within the boundary of the 16-county Chicago Combined Statistical Area lies the Chicago
urban area
An urban area is a human settlement with a high population density and an infrastructure of built environment. Urban areas originate through urbanization, and researchers categorize them as cities, towns, conurbations or suburbs. In urbani ...
, as well as 26 smaller urban areas. Some of the urban areas below may partially cross into other statistical areas. Only those situated primarily within the Chicago combined statistical area are listed here.
Economy

The Chicago metropolitan area is home to the corporate headquarters of 57
Fortune 1000
{{location map+ , United States , float=right , width=400, relief=1 , caption=''Fortune'' 1000 company headquarters locations. Top 20 companies labeled, places=
{{location map~ , United States , lat= 36.365378 , long= -94.217629 , label= Walmart, ...
companies, including
AbbVie Inc.,
Allstate,
Kraft Heinz
The Kraft Heinz Company (KHC), commonly known as Kraft Heinz (), is an American multinational food company formed by the merger of Kraft Foods Group, Inc. and the H.J. Heinz Company co-headquartered in Chicago and Pittsburgh. Kraft Heinz is t ...
,
McDonald's
McDonald's Corporation, doing business as McDonald's, is an American Multinational corporation, multinational fast food chain store, chain. As of 2024, it is the second largest by number of locations in the world, behind only the Chinese ch ...
,
Mondelez International
Mondelēz International, Inc. ( ) is an American Multinational corporation, multinational confectionery, food industry, food, Holding company, holding, drink industry, beverage and snack food company based in Chicago. Mondelez has an annual rev ...
,
Motorola
Motorola, Inc. () was an American multinational telecommunications company based in Schaumburg, Illinois. It was founded by brothers Paul and Joseph Galvin in 1928 and had been named Motorola since 1947. Many of Motorola's products had been ...
,
United Airlines
United Airlines, Inc. is a Major airlines of the United States, major airline in the United States headquartered in Chicago, Chicago, Illinois that operates an extensive domestic and international route network across the United States and six ...
,
Walgreens, and
more. The Chicago area also headquarters a wide variety of global financial institutions including
Citadel LLC,
Discover Financial Services,
Morningstar, Inc.
Morningstar, Inc. is an American financial services firm headquartered in Chicago, Illinois, founded by Joe Mansueto in 1984. It provides an array of investment research and investment management services.
With operations in 29 countries, Mornin ...
,
CNA Financial, and more. Chicago is home to the largest
futures exchange
A futures exchange or futures market is a central financial exchange where people can trade standardized futures contracts defined by the exchange. Futures contracts are derivatives contracts to buy or sell specific quantities of a commodity or ...
in the world, the
Chicago Mercantile Exchange
The Chicago Mercantile Exchange (CME) (often called "the Chicago Merc", or "the Merc") is an American derivatives marketplace based in Chicago and located at 20 S. Wacker Drive. The CME was founded in 1898 as the Chicago Butter and Egg Board ...
. In March 2008, the Chicago Mercantile Exchange announced its acquisition of NYMEX Holdings Inc, the parent company of the
New York Mercantile Exchange
The New York Mercantile Exchange (NYMEX) is a commodity futures exchange owned and operated by CME Group of Chicago. NYMEX is located at One North End Avenue in Brookfield Place in the Battery Park City section of Manhattan, New York City. ...
and Commodity Exchange. CME'S acquisition of NYMEX was completed in August 2008.
A key piece of infrastructure for several generations was the
Union Stock Yards
The Union Stock Yard & Transit Co., or The Yards, was the meatpacking district in Chicago for more than a century, starting in 1865. The district was formed by a group of railroad companies that acquired marshland and turned it into a vast cen ...
of Chicago, which from 1865 until 1971 penned and slaughtered millions of cattle and hogs into standardized cuts of
beef
Beef is the culinary name for meat from cattle (''Bos taurus''). Beef can be prepared in various ways; Cut of beef, cuts are often used for steak, which can be cooked to varying degrees of doneness, while trimmings are often Ground beef, grou ...
and
pork
Pork is the culinary name for the meat of the pig (''Sus domesticus''). It is the most commonly consumed meat worldwide, with evidence of pig animal husbandry, husbandry dating back to 8000–9000 BCE.
Pork is eaten both freshly cooke ...
. This prompted poet
Carl Sandburg to describe Chicago as the "Hog Butcher for the World".
The Chicago area, meanwhile, began to produce significant quantities of telecommunications gear, electronics, steel, crude oil derivatives, automobiles, and industrial capital goods.
By the early 2000s, Illinois' economy had moved toward a dependence on high-value-added services, such as financial trading,
higher education
Tertiary education (higher education, or post-secondary education) is the educational level following the completion of secondary education.
The World Bank defines tertiary education as including universities, colleges, and vocational schools ...
,
logistics
Logistics is the part of supply chain management that deals with the efficient forward and reverse flow of goods, services, and related information from the point of origin to the Consumption (economics), point of consumption according to the ...
, and health care. In some cases, these services clustered around institutions that hearkened back to Illinois's earlier economies. For example, the Chicago Mercantile Exchange, a trading exchange for global
derivatives, had begun its life as an agricultural
futures market
A futures exchange or futures market is a central financial exchange where people can trade standardized futures contracts defined by the exchange. Futures contracts are derivatives contracts to buy or sell specific quantities of a commodity or f ...
.
In 2007, the area ranked first among U.S. metro areas in the number of new and expanded corporate facilities. It ranked third in 2008, behind the
Houston–Sugar Land–Baytown and
Dallas–Fort Worth metropolitan areas, and ranked second behind the
New York metropolitan area
The New York metropolitan area, also called the Tri-State area and sometimes referred to as Greater New York, is the List of cities by GDP, largest metropolitan economy in the world, with a List of U.S. metropolitan areas by GDP, gross metropo ...
in 2009.
''
The Wall Street Journal
''The Wall Street Journal'' (''WSJ''), also referred to simply as the ''Journal,'' is an American newspaper based in New York City. The newspaper provides extensive coverage of news, especially business and finance. It operates on a subscriptio ...
'' summarized the Chicago area's economy in November 2006 with the comment that "Chicago has survived by repeatedly reinventing itself."
Transportation
Major airports
*
Chicago O'Hare International Airport (ORD)
*
Chicago Midway International Airport (MDW)
*
Milwaukee Mitchell International Airport
Milwaukee Mitchell International Airport is a civil–military airport south of downtown Milwaukee, Wisconsin, United States., effective April 17, 2025. It is included in the Federal Aviation Administration (FAA) National Plan of Integrated ...
(MKE) (located in the adjacent
Milwaukee metropolitan area
The Milwaukee metropolitan area (also known as Metro Milwaukee or Greater Milwaukee) is a major metropolitan area located in Southeastern Wisconsin, consisting of the city of Milwaukee and some of the surrounding area. There are several defini ...
)
*
Chicago Rockford International Airport (RFD) (located in the adjacent
Rockford metropolitan area)
*
Gary/Chicago International Airport (GYY)
Commercial ports
*
Port of Chicago
*
Port of Indiana-Burns Harbor
Transit systems
Commercial freight
Chicago has been at the center of the United States' railroad network since the 19th century. Almost all
Class I railroads serve the area, the most in North America.
Passenger
*
Chicago Transit Authority
The Chicago Transit Authority (CTA) is the operator of public transport, mass transit in Chicago, Illinois, United States, and some of its suburbs, including the trains of the Chicago "L" and List of Chicago Transit Authority bus routes, CTA bu ...
trains, locally referred to as
"the 'L'", (after "elevated train") serving Chicago and the near suburbs
*
Pace Suburban Bus operates suburban bus and regional vanpool, paratransit, and ride-matching services in the Chicagoland region.
*
Metra
Metra is the primary commuter rail system in the Chicago metropolitan area serving the city of Chicago and its surrounding suburbs via the Union Pacific Railroad, BNSF Railway, and other railroads. The system operates 243 train station, stati ...
run by the Northeast Illinois Regional Commuter Railroad Corporation:
** 4 lines serving southern Cook County and Will County
** 3 lines serving western Cook County, DuPage County, and Kane County
** 2 lines serving northern Cook County and Lake County
** 1 line serving northern Cook County, Lake County, and Kenosha County
** 1 line serving northwestern Cook County and McHenry County
*
South Shore Line shares the Metra Electric Line in Illinois and connects Chicago to
Gary,
Michigan City, and ending at
South Bend
South Bend is a city in St. Joseph County, Indiana, United States, and its county seat. It lies along the St. Joseph River (Lake Michigan), St. Joseph River near its southernmost bend, from which it derives its name. It is the List of cities in ...
.
*
Amtrak
The National Railroad Passenger Corporation, Trade name, doing business as Amtrak (; ), is the national Passenger train, passenger railroad company of the United States. It operates intercity rail service in 46 of the 48 contiguous United Stat ...
operates
Union Station
A union station, union terminal, joint station, or joint-use station is a railway station at which the tracks and facilities are shared by two or more separate railway company, railway companies, allowing passengers to connect conveniently bet ...
which is the major Amtrak passenger rail hub with connections to Metra and the within a few blocks of connections to several 'L' lines. Amtrak also operates a connecting station out of
Joliet.
Major highways
Interstates
*
Interstate 41 (I-41) runs concurrently with Interstate 94 from the northern terminus of the Tri-State Tollway to
Milwaukee
Milwaukee is the List of cities in Wisconsin, most populous city in the U.S. state of Wisconsin. Located on the western shore of Lake Michigan, it is the List of United States cities by population, 31st-most populous city in the United States ...
.
*
Interstate 55 (I-55) is the Adlai Stevenson Expy.
*
I-355 is the Veterans Memorial Tollway (formerly North-South Tollway).
*
I-57 is unofficially the "West Leg" of the Dan Ryan Expy.
*
I-65 has no name, whether official or unofficial.
*
I-80 is officially called the Borman Expy (cosigned with I-94), Kingery Expy (cosigned with I-94 for 3 miles), Tri-State Tollway (cosigned with I-294 for 4 miles) and is unofficially called the Moline Expy west of I-294.
*
I-88 is the Ronald Reagan Memorial Tollway (formerly East-West Tollway)
*
I-90
Interstate 90 (I-90) is an east–west transcontinental freeway and the longest Interstate Highway in the United States at . It begins in Seattle, Washington, and travels through the Pacific Northwest, Mountain states, Mountain West, Great Pla ...
is locally known as Jane Addams Tollway (formerly Northwest Tollway),
John F. Kennedy Expy (cosigned with I-94),
Dan Ryan Expy (cosigned with I-94), and Chicago Skyway Toll Bridge.
*
I-94 is Tri-State Tollway in Lake County, Edens Spur, Edens Expy, John F. Kennedy Expy (cosigned with I-90), Dan Ryan Expy (cosigned with I-90), Bishop Ford Frwy (formerly Calumet Expy), Kingery Expy (cosigned with I-80) and Borman Expy (cosigned with I-80).
*
I-190 is the John F. Kennedy Expy spur heading into
Chicago-O'Hare Int'l Airport.
*
I-290 is the Dwight D. Eisenhower Expy.
*
I-294 is the Tri-State Tollway.
Other main highways
* US Routes in the Illinois part of the area include:
US 6
U.S. Route 6 (US 6) or U.S. Highway 6 (US 6), also called the Grand Army of the Republic Highway, honoring the Grand Army of the Republic, American Civil War veterans association, is a main route of the United States Numbere ...
, U.S. Route 12 in Illinois, US 12, U.S. Route 14 in Illinois, US 14, U.S. Route 20 in Illinois, US 20, U.S. Route 30 in Illinois, US 30, U.S. Route 34 in Illinois, US 34, U.S. Route 41 in Illinois, US 41, U.S. Route 45 in Illinois, US 45, and U.S. Route 52 in Illinois, US 52.
* Illinois Route 53, an arterial north–south state highway running through Grundy, Will, DuPage, Cook and Lake counties
* U.S. Route 66 in Illinois, Historic US Route 66's eastern terminus is in Chicago.
Major corridors
In addition to the Chicago Loop, the metro area is home to a few important subregional corridors of commercial activities. Among them are:
* Illinois Technology and Research Corridor, along the Interstate 88 (Illinois), Ronald Reagan Memorial Tollway (Interstate 88)
* Golden Corridor, along the Interstate 90 in Illinois, Jane Addams Memorial Tollway (Interstate 90)
* Lakeshore Corridor, along the Edens Expressway and Tri-State Tollway
Culture
Sports
Listing of the professional sports teams in the Chicago metropolitan area
Major league professional teams:
* Major League Baseball, Major League Baseball (MLB)
** Chicago Cubs
** Chicago White Sox
* National Football League (NFL)
** Chicago Bears
* National Basketball Association, National Basketball Association (NBA)
** Chicago Bulls
* National Hockey League (NHL)
** Chicago Blackhawks
* Major League Soccer, Major League Soccer (MLS)
** Chicago Fire FC
Other professional teams:
* Women's National Basketball Association, Women's National Basketball Association (WNBA)
** Chicago Sky
* National Women's Soccer League, National Women's Soccer League (NWSL)
** Chicago Stars FC
* American Association of Professional Baseball (AA)
** Chicago Dogs
** Kane County Cougars
** Gary SouthShore RailCats
* American Hockey League, American Hockey League (AHL)
** Chicago Wolves
* NBA G League, NBA G League (NBAGL)
** Windy City Bulls
* Major League Rugby, Major League Rugby (MLR)
** Chicago Hounds (rugby union), Chicago Hounds
The Chicagoland Speedway oval track has hosted NASCAR Cup Series and IndyCar Series races.
The Chicago Marathon is one of the World Marathon Majors.
The Western Open and BMW Championship (PGA Tour), BMW Championship are PGA Tour tournaments that have been held primarily at golf courses near Chicago.
NCAA Division I College Sports Teams:
* Atlantic 10 Conference
** Loyola Ramblers, Loyola University Chicago Ramblers
* Big East Conference
** DePaul Blue Demons, DePaul University Blue Demons
* Big Ten Conference
** Northwestern Wildcats, Northwestern University Wildcats (Evanston, Illinois, Evanston)
* Mid-American Conference
** Northern Illinois Huskies, Northern Illinois University Huskies (DeKalb, Illinois, DeKalb)
* Missouri Valley Conference
** UIC Flames, University of Illinois Chicago Flames
** Valparaiso Beacons, Valparaiso University Beacons (Valparaiso, IN)
* Northeast Conference
** Chicago State Cougars, Chicago State University Cougars
Cuisine
* Chicago-style hot dog
* Chicago-style pizza
* Italian beef
* Caramel popcorn
Media
The two main newspapers are the ''
Chicago Tribune
The ''Chicago Tribune'' is an American daily newspaper based in Chicago, Illinois, United States. Founded in 1847, it was formerly self-styled as the "World's Greatest Newspaper", a slogan from which its once integrated WGN (AM), WGN radio and ...
'' and the ''Chicago Sun-Times''. Local television channels broadcasting to the Chicago market include WBBM-TV 2 (CBS), WMAQ-TV 5 (NBC), WLS-TV 7 (ABC), WGN-TV 9 (Ind), WTTW 11 (PBS), MeTV 23, WCIU-TV, WCIU 26 (CW), WFLD 32 (FOX), WCPX-TV 38 (Ion Television, Ion), WSNS-TV 44 (Telemundo), WPWR-TV 50 (MyNetworkTV), and WJYS-TV 62 (The Way). Radio stations serving the area include: WBBM (AM), WBEZ, WGN (AM), WMBI-FM, WMBI, WLS (AM), and WSCR.
Education

Elementary and secondary education within the Chicago metropolitan area is provided by dozens of different school districts, of which by far the largest is the Chicago Public Schools with 400,000 students. Numerous private and religious school systems are also found in the region, as well as a growing number of charter schools. Racial inequalities in education in the region remain widespread, often breaking along district boundaries; for instance, educational prospects vary widely for students in the Chicago Public Schools compared to those in some neighboring suburban schools.
Historically, the Chicago metropolitan area has been at the center of a number of national educational movements, from the free-flowing Winnetka Plan to the regimented Taylorism of the Gary Plan. In higher education,
University of Chicago
The University of Chicago (UChicago, Chicago, or UChi) is a Private university, private research university in Chicago, Illinois, United States. Its main campus is in the Hyde Park, Chicago, Hyde Park neighborhood on Chicago's South Side, Chic ...
founder William Rainey Harper was a leading early advocate of the junior college movement; Joliet Junior College is the nation's oldest continuously operating junior college today. Later U of C president Robert Maynard Hutchins was central to the Great Books movement, and programs of dialogic education arising from that legacy can be found today at the U of C, at Shimer College, and in the City Colleges of Chicago and Oakton College in the Northwest suburbs.
Area codes
From 1947 until 1988, the Illinois portion of the Chicago metro area was served by a single North American Numbering Plan, area code, 312, which abutted the 815 area code. In 1988 the 708 area code was introduced and the 312 area code became exclusive to the city of Chicago.
It became common to call suburbanites "708'ers", in reference to their area code.
The 708 area code was partitioned in 1996 into three area codes, serving different portions of the metro area: 630, 708, and 847.
At the same time that the 708 area code was running out of phone numbers, the 312 area code in Chicago was also exhausting its supply of available numbers. As a result, the city of Chicago was divided into two area codes, 312 and 773. Rather than divide the city by a north–south area code, the central business district retained the 312 area code, while the remainder of the city took the new 773 code.
In 2002, the 847 area code was supplemented with the overlay area code 224. In February 2007, the 815 area code (serving outlying portions of the metro area) was supplemented with the overlay area code 779. In October 2007, the overlay area code 331 was implemented to supplement the 630 area with additional numbers.
Plans are in place for overlay codes in the 708, 773, and 312 regions as those area codes become exhausted in the future.
* Area code 312, 312 Chicago - City (The Chicago Loop, Loop and central neighborhoods, e.g. the Near North Side)
* Area code 773, 773 Chicago - City (Everywhere else within the city limits, excluding central area)
* 872 Chicago - City (overlay for 312 & 773, effective November 7, 2009)
* 847/224 (North and Northwest Suburbs)
* Area codes 630 and 331, 630/331 (Outer Western Suburbs)
* Area code 708, 708 (South and Near West Suburbs)
* Area codes 815 and 779, 815/779 (
Rockford & Joliet: Far Northwest/Southwest Suburbs)
* Area code 219, 219 (Northwest Indiana)
* Area code 574, 574 (North-central Indiana)
* Area code 262, 262 (Southeast Wisconsin surrounding Milwaukee County)
Proposed overlays
* 464 overlay for 708 (January 21, 2022, rollout)
See also
* Index of Illinois-related articles
References
Further reading
* Fischer, Paul B. (July 28, 1993).
Racial and Locational Patterns of Subsidized Housing in the Chicago Suburbs: A Report to the MacArthur Foundation'
Archive. Lake Forest, Ill.: Lake Forest College. Report to the MacArthur Foundation.
* Lewinnek, Elaine (2014). ''The Working Man's Reward: Chicago's Early Suburbs and the Roots of American Sprawl''. Oxford: Oxford University Press.
External links
''Encyclopedia of Chicago'' (2004) comprehensive coverage of city and suburbs, past and present
U.S. Census Urbanized Area Outline Map (2000)Chicago-Naperville-Michigan City, IL-IN-WI Combined Statistical Area (2012) mapIllinois CBSAs and Counties (2013) mapU.S. Census Bureau Chicago city, Illinois QuickFacts
{{Authority control
Chicago metropolitan area,
Chicago, *
Metropolitan areas of Illinois
Metropolitan areas of Indiana
Metropolitan areas of Wisconsin
Regions of Illinois
Regions of Indiana
Regions of Wisconsin
1837 establishments in the United States