These are the largest corporate groups and holding companies in Illinois. They are mostly mid-sized to large firms operating in a diverse range of sectors. The list features major players in healthcare, such as OSF HealthCare, an integrated health system, and Walgreens Boots Alliance, an integrated healthcare and retail company. Other prominent companies include Molson Coors Beverage Company, a global producer of beverages, and RRD, a global provider of marketing and supply chain solutions.
A notable pattern among these companies is their headquarters distribution. While many are based in Chicago, a significant number of large firms are headquartered outside the city, in places like Deerfield, Northbrook, Peoria, and Springfield. This indicates a broader distribution of major corporate entities across Illinois beyond its primary urban center.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
Walgreens Boots Alliancewalgreens.com
Integrated healthcare and retail company operating thousands of pharmacy locations, providing medicines, health services, beauty products, and digital convenience globally. |
141,576 | |||
| 2 | 41,201 | ||||
| 3 |
UL Solutionsul.com
Global provider of safety testing, certification, inspection, auditing, and advisory services ensuring product security, sustainability, and market trust. |
14,487 | |||
| 4 |
OSF HealthCareosfhealthcare.org
Integrated health system with hospitals, home care, nursing colleges, digital health services, philanthropic foundation, and healthcare innovation investments. |
12,433 | |||
| 5 |
Molson Coors Beverage Companymolsoncoors.com
Global producer of beer, energy drinks, and canned cocktails including brands like Miller Lite and Blue Moon while promoting responsible alcohol consumption. |
12,299 | |||
| 6 |
Hospital Sisters Health Systemhshs.org
Multi-institutional health system providing integrated, patient-centered care through hospitals, clinics, and physician partners in Illinois and Wisconsin. |
11,854 | |||
| 7 |
Baker Tilly USbakertilly.com
A leading advisory CPA firm with a coast-to-coast and global presence, part of Baker Tilly International network with 43,000 professionals |
10,594 | |||
| 8 |
LKQ Corporationlkqcorp.com
Largest provider of alternative collision, recycled, and remanufactured auto parts, plus specialty aftermarket equipment and accessories across multiple countries. |
8,450 | |||
| 9 |
Conagra Brandsconagrabrands.com
Diverse team managing iconic and emerging food brands with a focus on innovation, integrity, and consistent business results. |
7,846 | |||
| 10 |
Carle Healthcarle.org
Integrated healthcare system combining clinical care, insurance, research, education, and philanthropy to improve patient outcomes and community health. |
6,896 | |||
| 11 |
Adtalem Global Educationcovista.com
A leading medical and healthcare education provider, focusing on workforce talent needs through education, certifications, upskilling programs with a diverse, inclusive approach |
5,688 | |||
| 12 |
Ryan Specialtyryanspecialty.com
International specialty insurance firm providing underwriting, product development, administration, risk management, and wholesale brokerage services for brokers and carriers. |
4,562 | |||
| 13 |
The Heico Companies LLCheicocompanies.com
A privately held company with 74 separate acquisitions in manufacturing, construction, and industrial services, focused on growth and success |
4,427 | |||
| 14 |
Allscriptsveradigm.com
Healthcare technology company with a focus on transforming healthcare through innovative solutions Follow us at our new LinkedIn page |
4,337 | |||
| 15 |
@propertiesatproperties.com
A top real estate brokerage firm in Illinois, offering expert advice, innovative technology, and award-winning services to local homebuyers and sellers |
3,970 | |||
| 16 |
Baird & Warnerbairdwarner.com
Illinois' largest family-owned real estate services company, known for experience, innovation, and integrity, with nearly 2,500 associates and top rankings nationally |
3,957 | |||
| 17 | 3,652 | ||||
| 18 |
Chartischartis.com
Consulting firm specializing in healthcare strategy, transformation, and operational models to improve affordability, accessibility, safety, and patient experience. |
3,598 | |||
| 19 |
Cushman & Wakefield - Formerly DTZcushmanwakefield.com
A global leader in commercial real estate services, providing insights and value for occupiers and investors worldwide through various core services |
3,518 | |||
| 20 |
LSC Communicationslsccom.com
Provider of print and digital media solutions, serving publishers, brands, retailers with advanced technology and efficient supply chain services. |
3,507 | |||
| 21 | 3,386 | ||||
| 22 |
Applied Systemswww1.appliedsystems.com
A leading provider of innovative cloud software for the insurance industry, driving transformation through digitization, automation, and new partnerships |
2,813 | |||
| 23 |
Reyes Beverage Groupreyesbeveragegroup.com
National family-owned distributor delivering beer, spirits, wine, and non-alcoholic beverages to retail accounts while prioritizing employee safety, integrity, and customer profitability across the nation. |
2,794 | |||
| 24 |
Claycoclaycorp.com
A full-service real estate development, architecture, engineering, and construction firm delivering high-quality solutions within North America on time and on budget |
2,744 | |||
| 25 |
Fortune Brands Innovationsfbin.com
Designs and manufactures water innovations, outdoor living products, security solutions, and kitchen and bath cabinets for homeowners. |
2,603 | |||
Want more companies than this list?This page shows the largest ones only. Connect to Tamtam to see every company that matches, filter by size, industry or growth, and reach their decision-makers. | |||||
| 26 |
Ritchie Bros.rbauction.com
A global asset management and disposition company offering end-to-end solutions for buying and selling used heavy equipment, trucks, and other assets across multiple sectors |
2,573 | |||
| 27 |
Cars Commercecarscommerce.inc
Online platform connecting car buyers and sellers through innovative tools and services, supporting automotive retail and career growth nationwide. |
2,285 | |||
| 28 |
IMEGimegcorp.com
IMEG is a national engineering and design consulting company focusing on people-centered engineering, high-performing building systems, infrastructure, and construction services |
2,268 | |||
| 29 |
Ryersonryerson.com
A global metal processing and distribution company with operations in the US, Mexico, Canada, and China, employing approximately 4,200 people |
2,267 | |||
| 30 |
Career Education Corporationperdoceoed.com
Educational services company offering diverse learning formats (online, campus-based, blended) through AIU and CTU with innovative technology and personalized courses |
2,250 | |||
| 31 |
Addison Groupaddisongroup.com
Professional services firm specializing in talent solutions, consulting, recruiting, and executive search across various sectors, recognized for industry excellence and growth |
2,130 | |||
| 32 |
Tecta America Commercial Roofingtectaamerica.com
A leading commercial roofing contractor with over 90 locations, providing nationwide roofing solutions including installation, maintenance, disaster response, and asset management |
1,999 | |||
| 33 |
Duravantduravant.com
A global leader in automation equipment, Duravant offers premium products and solutions to optimize safety, productivity, and efficiency for producers worldwide |
1,974 | |||
| 34 |
Northwest Community Healthcareendeavorhealth.org
Endeavor Health is a united healthcare system providing personalized patient experiences and world-class care through convenient access and collaboration #OurEndeavor |
1,916 | |||
| 35 | 1,866 | ||||
| 36 |
Blessing Healthblessinghealth.org
An integrated health system with hospitals, provider groups, specialty businesses, nursing college, and charitable foundation providing high-quality care to communities |
1,758 | |||
| 37 |
Valassis Marketing Solutionsrrd.com
Innovative marketing solutions company powering business-to-human connections, driving economic growth, and accelerating revenue potential for brands through data intelligence and technology |
1,743 | |||
| 38 |
Syndigosyndigo.com
Cloud-based product information management, master data management, and content distribution network serving global enterprises across grocery, healthcare, automotive, and retail sectors for commerce. |
1,726 | |||
| 39 |
The Aspen Groupteamtag.com
Supports providers across dental, medical aesthetics, urgent care, and veterinary medicine, empowering clinicians and expanding access to high-quality care nationwide through various brands and education. |
1,697 | |||
| 40 |
VillageMDvillagemd.com
The company provides accessible healthcare services through primary, multi-specialty, and urgent care providers in various settings to improve patient outcomes and reduce healthcare costs |
1,683 | |||
| 41 |
Enova Internationalenova.com
A financial services company offering online lending to small businesses and underserved consumers, providing over $52 billion in loans |
1,570 | |||
| 42 |
Riverside Healthcareriversidehealthcare.org
Integrated healthcare system providing inpatient and outpatient care, senior living communities, fundraising, fitness center, counseling programs, pharmacy services, and career opportunities in various healthcare fields |
1,538 | |||
| 43 |
Coeur Mining, Inc.coeur.com
Precious metals producer with mines in North America, focusing on responsible mining while prioritizing employee safety, environmental protection, and community engagement through teamwork and innovation |
1,465 | |||
| 44 |
RLI Insurance Companyrlicorp.com
Specialty insurer focusing on niche property, casualty, and surety markets, providing customized insurance products and superior customer service. |
1,430 | |||
| 45 |
Advanced Groupadvancedgroup.com
Specializing in talent acquisition, outsourcing, and professional services, we provide strategic resourcing, staffing, consulting, and recruitment process outsourcing to various industries |
1,414 | |||
| 46 |
JBT FoodTechjbtc.com
Design, manufacture, and service customized industrial equipment for processing meat, seafood, poultry, bakery, dairy, juice, and packaged foods worldwide. |
1,407 | |||
| 47 |
Superior Ambulance Servicesuperiorambulance.com
A family-owned EMS provider with over 1600 employees and 200 ambulances, offering services in Illinois, Indiana, and Michigan since 1959 |
1,398 | |||
| 48 |
National Express LLCsummitllc.com
North American transportation company focused on safety, quality, customer service, and positive employee relations across multiple locations. |
1,365 | |||
| 49 |
Flying Food Groupflyingfood.com
A US based company providing authentic meals, logistics, and digital services to the travel and retail industries, with a focus on diversity and giving back |
1,273 | |||
| 50 |
MacLean-Foggmacleanfogg.com
A global enterprise founded in 1925 that specializes in providing solutions, products, and services with world-class quality to customers worldwide |
1,261 | |||
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How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 11, 2026.
More company lists in Illinois
- The largest companies in Illinois 4,687
- Multinational companies in Illinois 831
- Manufacturers in Illinois 528
- Education providers in Illinois 370
- Financial services firms in Illinois 352
- Professional services firms in Illinois 339
- Companies with in-house R&D in Illinois 322
- Hardware manufacturers in Illinois 296
- IT Services and IT Consulting companies in Illinois 294
- Hospitals and Health Care companies in Illinois 280
- IT services companies in Illinois 274
- Healthcare providers in Illinois 262
- Retail chains in Illinois 260
- Financial Services companies in Illinois 248
- Critical infrastructure operators in Illinois 241
- Consulting firms in Illinois 238
- Logistics companies in Illinois 228
- Transportation, Logistics, Supply Chain and Storage companies in Illinois 215
- SaaS companies in Illinois 182
- Companies with a mobile app in Illinois 178
- Family-owned companies in Illinois 166
- Subscription businesses in Illinois 160
- Publicly traded companies in Illinois 154
- Public sector organisations in Illinois 147
The same list elsewhere in United States
- Corporate groups and holding companies in the United States 2,829
- Corporate groups and holding companies in California 270
- Corporate groups and holding companies in New York State 245
- Corporate groups and holding companies in Texas 238
- Corporate groups and holding companies in Florida 182
- Corporate groups and holding companies in Pennsylvania 120
- Corporate groups and holding companies in Ohio 104
- Corporate groups and holding companies in Georgia 90
- Corporate groups and holding companies in Michigan 90
- Corporate groups and holding companies in Alabama 89
- Corporate groups and holding companies in Massachusetts 87
- Corporate groups and holding companies in New Jersey 79
- Corporate groups and holding companies in Virginia 78
- Corporate groups and holding companies in North Carolina 70
- Corporate groups and holding companies in Tennessee 60
- Corporate groups and holding companies in Wisconsin 60
- Corporate groups and holding companies in Missouri 59
- Corporate groups and holding companies in Minnesota 57
- Corporate groups and holding companies in Indiana 54
- Corporate groups and holding companies in Colorado 52
- Corporate groups and holding companies in New York 152
- Corporate groups and holding companies in Houston 74
- Corporate groups and holding companies in Chicago 64
- Corporate groups and holding companies in Atlanta 47