List of major companies in the Chicago metropolitan area

The following companies have headquarters within the Chicago city limits:

* Accenture
* Aon Corporation (Ranked #199 on the Fortune 500)
* Bally Total Fitness
* Boeing (Ranked #21 on the Fortune 500)
* CareerBuilder
* Chicago Board of Trade (pending merger with Chicago Mercantile Exchange to form CME group).
* Chicago Board Options Exchange
* Chicago Mercantile Exchange
* Chicago Stock Exchange
* Citadel Investment Group
* Classified Ventures
* Click Commerce
* CNA Financial (an affiliate of Loews Corporation)
* Diamond Management & Technology Consultants
* Encyclopædia Britannica, Inc.
* Equity Office Properties Trust (Ranked #493 on the Fortune 500)
* Exelon Corporation (Ranked #126 on the Fortune 500)
* Fellowes
* GATX Corporation
* General Growth Properties
* Global Hyatt Corporation
* Hostway
* Integrys Energy Group, Inc.
* Jones Lang LaSalle
* Kerasotes Theatres
* La Petite Academy
* Merisant
* Metal Management
* Midway Games
* Morningstar, Inc.
* Morton Salt
* National Stock Exchange
* Navigon
* NAVTEQ
* Northern Trust
* Old Republic International
* Orbitz
* Playboy Enterprises
* Quaker Oats Company, a unit of PepsiCo
* R.R. Donnelley & Sons (Ranked #362 on the Fortune 500)
* Ryerson, Inc.
* Shorebank
* Skidmore, Owings, and Merrill
* Smurfit-Stone Container Corporation (Ranked #255 on the Fortune 500)
* SSA Global Technologies
* Telephone and Data Systems Incorporated
* Tootsie Roll Industries
* TransUnion
* Tribune Company (Ranked #323 on the Fortune 500)
* True Value
* Ubid
* United Airlines (Corporate Offices) (Fortune 500)
* US Cellular
* USG Corporation (Ranked #458 on the Fortune 500)
* Unitrin (S&P 400 MidCap, S&P 1500 Super Comp)
* Whittman-Hart
* Wilson Sporting Goods
* World Book
* WM. Wrigley Jr. Company

The following companies are based in Chicago's suburbs:
* Abbott Laboratories (Abbott Park, Illinois) (Fortune 500)
* ACCO Brands (Lincolnshire, Illinois)
* Ace Hardware (Oak Brook, Illinois)
* ACNielsen (Schaumburg, Illinois)
* Alberto-Culver (Melrose Park, Illinois)
* Allstate (Northbrook, Illinois) (Fortune 500)
* American Unit Inc (Schaumburg, Illinois)
* Andrew Corporation (Westchester, Illinois)
* Anixter International (Glenview, Illinois)
* Aquascape, Inc. (St. Charles, Illinois)
* Azteca Foods (Summit, Illinois)
* Baxter International (Deerfield, Illinois) (Fortune 500)
* BFG Technologies (Lake Forest, Illinois)
* Blistex, Incorporated (Oak Brook, Illinois)
* BRK Brands aka First Alert (Aurora, Illinois)
* Brunswick Corporation (Lake Forest, Illinois) (Fortune 500)
* Calamos Holdings LLC (Naperville, Illinois)
* Career Education Corporation (Hoffman Estates, Illinois)
* CDW (Vernon Hills, Illinois) (Ranked #376 on the Fortune 500)
* CF Industries (Deerfield, Illinois)
* Corn Products International (Westchester, Illinois)
* Così (Deerfield, Illinois)
* Coskata (Warrenville, Illinois)
* Crate and Barrel (Northbrook, Illinois)
* Culligan (Rosemont, Illinois)
* DeVry University (Oakbrook Terrace, Illinois)
* Discover Financial Services (Riverwoods, Illinois)
* Donlen Corporation (Northbrook, Illinois)
* Electro-Motive Diesel (McCook, Illinois)
* Fortune Brands (Jim Beam, Courvoisier, Titleist, and many other brands) (Deerfield, Illinois) (Fortune 500)
* Griffith Laboratories (Alsip, Illinois)
* Hendrickson Int'l Corp. (Lemont, Illinois; a subsidiary of The Boler Company (Itasca, Illinois))
* Hewitt Associates (Lincolnshire, Illinois) (Fortune 500)
* Hospira (Lake Forest, Illinois)
* IDEX Corporation (Northbrook, Illinois)
* Illinois Tool Works (Glenview, Illinois) (Fortune 500)
* Kraft Foods (Northfield, Illinois)
* McDonald's Corporation (Oak Brook, Illinois) (Fortune 500)
* Molex (Lisle, Illinois)
* Motorola (Schaumburg, Illinois) (Fortune 500)
* Nalco Holding Company (Naperville, Illinois)
* Namco Cybertainment (Bensenville, Illinois; a subsidiary of Japan-based Namco)
* Navistar International Corporation (Warrenville, Illinois) (Fortune 500)
* Nicor (Naperville, Illinois) (S&P 500)
* NiSource (Merrillville, Indiana) (Fortune 500)
* Northfield Laboratories (Evanston, Illinois)
* OfficeMax (Naperville, Illinois)
* Pactiv (Lake Forest, Illinois)
* Pampered Chef (Addison, Illinois)
* Portillo's Restaurants (Oakbrook Terrace, Illinois)
* Rand McNally (Skokie, Illinois), a subsidiary of Quebecor World
* Redbox Automated Retail, LLC (Oakbrook Terrace, Illinois)
* Sanford (Oak Brook, Illinois; a division of Newell Rubbermaid)
* Sara Lee (Downers Grove, Illinois) (Fortune 500)
* Sauer-Danfoss (Lincolnshire, Illinois)
* Sears Holdings (Hoffman Estates, Illinois) (Fortune 500)
* Shure Incorporated (Niles, Illinois)
* SIRVA (Westmont, Illinois)
* Solo Cup Company (Highland Park, Illinois)
* Stepan Company (Northfield, Illinois)
* TAP Pharmaceuticals (Lake Forest, Illinois)
* Tellabs (Naperville, Illinois)
* Tenneco (Lake Forest, IL) (Fortune 500)
* Turtle Wax (Willowbrook, Illinois)
* Ulta (Romeoville, Illinois)
* Underwriters Laboratories (Northbrook, Illinois)
* United Airlines(Base of Operations) (Elk Grove Township) (Fortune 500)
* United Stationers (Deerfield, Illinois) (Fortune 500)
* U.S. Foodservice (Rosemont, Illinois)
* USRobotics (Schaumburg, Illinois)
* Vanee Foods Company, Inc. (Berkeley, Illinois)
* Van Kampen Investments (Oakbrook Terrace, Illinois)
* Velsicol Chemical Corporation (Rosemont, Illinois)
* Walgreens (Deerfield, Illinois) (Fortune 500)
* Weber-Stephen Products Company (Palatine, Illinois)
* Westell (Aurora, Illinois)
* WMS Gaming (Waukegan, Illinois)
* World Dryer (Berkeley, Illinois; a subsidiary of Carrier Commercial Refrigeration)
* W.W. Grainger (Lake Forest, Illinois) (Fortune 500)
* Zebra Technologies (Vernon Hills, Illinois)
* Zenith Electronics Corporation (Lincolnshire, Illinois; a subsidiary of South Korea-based LG Electronics)

There are other large corporations with an established presence in Chicago and/or its suburbs (but whose corporate headquarters are located elsewhere), including:
*ABN AMRO (Asset Management)
*Acxiom (Downers Grove, Illinois)
*ACS (Schaumburg, Illinois) (Fortune 500)
*ALDI (U.S. headquarters: Batavia, Illinois)
*Akzo Nobel (Polymer Chemicals Unit)
*Astellas Pharma (Deerfield, Illinois)
*AT&T
*Bank of America
*Bank of Montreal (Harris Bankcorp, BMO Capital Markets)
*BP (Warrenville and Naperville, Illinois; Whiting, Indiana)
*Canon USA (Itasca, Illinois)
*Caterpillar Inc. (Montgomery, Illinois)
*CITGO (Lemont Refinery, Lemont, Illinois)
*ConAgra (Downers Grove, Illinois)
*Continental Automotive Systems (Temic) (Deer Park, Illinois)
*CSX Transportation (Northern Region Operations Center) (Calumet City, Illinois)
*FANUC Robotics (Hoffman Estates, Illinois)
*Fitch Ratings
*Ford Motor Company (Chicago Assembly, Chicago Heights Stamping)
*Fujifilm (Fujifilm Medical) Hanover Park, Illinois)
*GE
*Goldman Sachs
*HSBC Finance, a subsidiary of HSBC (Mettawa, Illinois)
*IBM
*Ineos/Innovene (Chicago and Naperville, Illinois; Whiting, Indiana)
*JPMorgan Chase & Co. (See: "Bank One")
*Lucent Technologies
*McKesson Corporation (Wheeling, Illinois)
*McGraw-Hill Companies (Chicago Loop)
*Microsoft Corporation (Chicago Loop; Downers Grove, Illinois; Northlake, Illinois (data center))
*Mintel
*Mitsubishi Electric (Mitsubishi Electric Automation, Inc.) (Vernon Hills, Illinois)
*Mittal Steel Company (U.S. headquarters: Chicago Loop; plants in Riverdale, Illinois, East Chicago, Indiana, and Burns Harbor, Indiana)
*Mori Seiki (U.S. headquarters: Rolling Meadows, Illinois)
*NEC (NEC Display Solutions of America) (Itasca, Illinois)
*Nortel (Schaumburg, Illinois)
*Northrop Grumman Electronic Systems (Rolling Meadows, Illinois)
*Omron (Schaumburg, Bannockburn, St. Charles)
*Panasonic Corporation of North America (Panasonic Factory Solutions Company of America) (Buffalo Grove, Illinois)
*Pearson Education, publishing as Scott Foresman (Glenview, Illinois)
*PepsiAmericas (corporate offices) (Schaumburg, Illinois)
*Popular, Inc. (Banco Popular North America) (Rosemont, Illinois)
*Rexam
*Robert Bosch Corp. (Broadview, Illinois (automotive aftermarket); Mount Prospect, Illinois (production tools); Hoffman Estates, Illinois (Bosch Rexroth))
*SAP AG (Downers Grove, Illinois)
*Schneider Electric (Palatine, Illinois)
*Siemens Healthcare Diagnostics (U.S. headquarters: Deerfield, Illinois)
*Siemens Medical Solutions (Hoffman Estates, Illinois)
*SSAB North America (Lisle, Illinois)
*STMicroelectronics (Schaumburg, Illinois)
*Takeda Pharmaceutical Company (U.S. headquarters: Deerfield, Illinois)
*UBS AG
*Unilever (Home & Personal Care North America) (Chicago)
*UPS (CACH) (Hodgkins, Illinois)
*UOP LLC, a subsidiary of Honeywell (Des Plaines, Illinois)
*U.S. Steel (Gary Works) (Gary, Indiana)
*XL Capital (Chicago Loop, Schaumburg, Illinois)
*Yaskawa Electric America (Waukegan, Illinois)
*ZF Friedrichshafen (Vernon Hills, Illinois)
*Zurich Financial Services (Schaumburg, Illinois)