| # | Company | Employees |
|---|---|---|
| 1 |
Univar Solutionsunivarsolutions.com
Distributes chemicals and ingredients globally, provides value-added services, and offers expertise in market knowledge, formulation, logistics, and digital tools. |
9,326 |
| 2 |
Dover Corporationdovercorporation.com
A global manufacturer and solutions provider delivering innovative equipment, components, and digital solutions across various industries with operational agility and entrepreneurial approach |
6,338 |
| 3 |
ATI Physical Therapyatipt.com
Nationwide physical therapy clinics providing specialized treatments, employer solutions, and athletic training focused on patient-centered care and professional growth. |
5,310 |
| 4 |
Ensonoensono.com
Ensono is a technology adviser and managed service provider, specializing in digital transformation, cloud migration, and application modernization for businesses worldwide |
3,646 |
| 5 |
Cooper's Hawk Winery and Restaurantschwinery.com
An elegant tasting room and scratch kitchen restaurant chain with a large wine club, multiple locations, award-winning wines, and celebrity partnerships |
3,605 |
| 6 |
Midwestern Universitymidwestern.edu
Not-for-profit graduate institution offering health science degrees including medicine, pharmacy, therapy, psychology, nursing, dentistry, optometry, and veterinary medicine |
3,419 |
| 7 |
Duly Health and Caredulyhealthandcare.com
Duly Health and Care is a leading medical group focused on helping individuals achieve their extraordinary health potential with over 900 physicians |
3,131 |
| 8 |
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 |
| 9 |
Fresh Thyme Marketww2.freshthyme.com
Fresh Thyme Market is committed to offering real, healthy foods at affordable prices with a focus on fresh, local, and organic products Passionate about healthy living |
1,754 |
| 10 |
DuPage Medical Groupdulyhealthandcare.com
Duly Health and Care is a multi-specialty medical group focused on helping individuals achieve extraordinary health and wellness through personalized care |
1,488 |
| 11 |
CompTIAcomptia.org
An organization representing IT industry members, offering educational programs, research, certifications, and advocacy to advance industry growth and benefit organizations |
1,325 |
| 12 |
Advocate Medical Groupadvocatehealth.com
Integrated medical group in the Chicagoland area with primary care, specialty services, imaging, and community-based practices, committed to delivering outstanding healthcare outcomes and service |
1,152 |
| 13 |
Ameriprise Financialameriprise.com
This company specializes in personalized financial planning, taking into account all aspects of clients' financial situations to help achieve their goals |
1,133 |
| 14 |
3Cloud3cloudsolutions.com
Leading Microsoft Azure partner, offering expertise in infrastructure, data, analytics, and application innovation to solve complex business problems. |
1,042 |
| 15 | 983 | |
| 16 |
Abercrombie & Kent USAabercrombiekent.com
An unrivaled luxury travel provider offering small-group journeys, tailor-made experiences, private jet trips, and philanthropic partnerships in over 100 countries |
940 |
| 17 |
Illinois Tollwaylinktr.ee
The Illinois Tollway operates a user-fee system of interstate tollways in Northern Illinois, providing safe and efficient highways and services to customers |
895 |
| 18 |
Corelle Brandscorelle.com
A company focused on creating joy through innovative cooking and food storage products, embracing diversity and encouraging growth and development |
888 |
| 19 |
PSG, a Dover companypsgdover.com
Global expert in pump, metering, and dispensing solutions for critical fluids, focusing on performance, reliability, efficiency, and sustainability in various industries worldwide |
887 |
| 20 |
Roadrunnershiproadrunnerfreight.com
Optimized long haul freight shipping using data-driven direct metro-to-metro routes, partnering with owner operators and team drivers nationwide. |
864 |
| 21 |
Roadrunner Transportation Systemsrrts.com
A leading transportation and logistics provider offering asset-right and asset-light solutions through Roadrunner, Active On-Demand, and Ascent Global Logistics brands |
842 |
| 22 |
PLZ Corpplzcorp.com
Develops, manufactures, packages, and distributes a comprehensive line of contract fill, branded, and private-label specialty aerosol products for home and industrial use. |
822 |
| 23 |
Sentinel Technologiessentinel.com
Leader in IT solutions with focus on innovative, practical services for communication, data center, cloud, and managed services Recognized for employee commitment and growth |
791 |
| 24 |
Elkay Manufacturingelkay.com
Manufacturer of high-quality sinks, water coolers, and filtration systems, while providing turnkey commercial branded interior design services for restaurants and hospitality industries. |
787 |
| 25 |
Private Home Care Services, LLCprivatehomecareservices.com
Private Home Care Services provides personalized non-medical home care for seniors, offering assistance with daily living activities, personal care, medication reminders, and more in a social caregiving model |
786 |
| 26 |
Flexcoflexco.com
providing products and services to maximize belt conveyor uptime, productivity, and safety for various industries worldwide |
758 |
| 27 |
ServiceMaster DSIservicemasterrestore.com
A management group providing residential and commercial disaster restoration services through ServiceMaster DSI and ServiceMaster Recovery Management brands nationwide and globally |
652 |
| 28 |
Nexeo Solutionsunivarsolutions.com
Global chemical and ingredient distributor providing value-added services, formulation expertise, logistics, and digital tools to diverse industries. |
646 |
| 29 |
Silgan Closuressilgancls.com
Specializing in closures for food and beverage products, we design tamper-evident seals for global supply, ensuring product integrity and safety |
637 |
| 30 |
Maker's Pridemakerspride.com
Contract manufacturing partner producing diverse food products including snacks, baked goods, nutrition, fresh, and frozen foods across North America. |
619 |
| 31 |
Performance Healthperformancehealth.com
A global leader in rehabilitation, recovery, and sports performance, providing solutions through best-in-class brands and a wide range of clinical products |
583 |
| 32 |
Advocate Good Samaritan Hospitaladvocatehealth.com
A leading healthcare provider in Illinois, committed to providing clinically excellent and compassionate care through strong partnerships with physicians and outstanding nursing staff |
548 |
| 33 |
Formidiumformidium.com
Global leader in specialized fund administration solutions, offering proprietary technology for accurate accounting, investor onboarding, and access to alternative investments worldwide |
545 |
| 34 |
Physicians Revenue Group, Inc.prgmd.com
A leading provider of medical billing services and revenue cycle management solutions, helping healthcare providers improve financial performance with experienced professionals and customized solutions |
519 |
| 35 |
Vehicle Service Group, A Dover Companyvsgdover.com
A leading global provider of vehicle lifts, wheel service systems, and collision repair equipment, dedicated to helping others work quickly and safely |
499 |
| 36 |
Neighborhood Loansneighborhoodloans.com
Nationwide mortgage lender empowering home buyers and owners with transparent, process-driven service, dedicated to assisting borrowers every step of the way |
487 |
| 37 |
Healthcare Financial Management Association (HFMA)hfma.org
This organization provides guidance, tools, and education to finance professionals in healthcare to navigate industry challenges and lead their organizations forward |
464 |
| 38 |
Addus Home Healthaddus.com
Providing high-quality in-home supportive services in the Chicagoland area, enabling clients to stay comfortably and confidently in their own homes |
454 |
| 39 |
Downers Grove School District 58dg58.org
District 58 provides quality education and support services to over 5,000 students and 600 staff at 11 elementary schools and 2 middle schools |
412 |
| 40 |
Sevan Multi-Site Solutionssevan.com
A leading provider of innovative design, program management, construction services, and data analytics for organizations with multiple sites |
390 |
| 41 |
National Technologies (NTI), a Network Connex Companyntitech.com
A high-quality provider of fiber optic and data center installation services, offering mission-critical deployment capabilities and turnkey solutions with a customer-first mindset |
388 |
| 42 |
Network Connexnetworkconnex.com
A consortium of industry-leading firms providing end-to-end digital communications infrastructure services for rapid, high-quality solution design and implementation |
386 |
| 43 |
Community High School District 99 in Downers Grovecsd99.org
A school district with award-winning high schools serving over 5,300 students from several communities, focusing on student development and achievements |
329 |
| 44 |
MicroTekmclabs.com
Global leader in corporate training and meeting facilities, providing state-of-the-art technology, customizable event spaces, and comprehensive support services for organizations worldwide |
316 |
| 45 |
Thomson Industries (A Regal Rexnord Brand)thomsonlinear.com
The company specializes in providing optimal linear motion control solutions for machine builders, focusing on performance, life, and cost balance |
270 |
| 46 |
Vein Clinics of Americaveinclinics.com
A nationwide network of specialized physicians offering minimally invasive treatments for vein diseases, committed to promoting from within and serving local communities |
255 |
| 47 |
Chemring Energetic Deviceschemring.com
Manufactures mission-critical ordnance, pyro-mechanical components, and electronics for defense and aerospace industries, including aircraft life support, missile systems, space applications, and test equipment. |
228 |
| 48 |
Hirose Electric Americashirose.com
Develops and supplies electric and electronic connectors, powering devices and systems, enabling seamless communication between various technologies and applications. |
190 |
| 49 |
AmeriPro Roofingameriproroofing.com
AmeriPro Roofing ensures your family's protection by offering expert roof inspections, repairs, preventative maintenance, and assistance with insurance claims |
177 |
| 50 |
Gibson Electricgibsonelec.com
This company offers electrical and telecommunications services for various industries, focusing on safety, quality, reliability, customer satisfaction, and efficient project completion |
165 |
| 51 |
Celegencecelegence.com
Global regulatory affairs support for Life Sciences companies, offering expertise in strategy, submission management, and compliance through a team of consultants worldwide |
161 |
| 52 |
Adreimaadreima.com
Adreima provides specialized revenue cycle management solutions for over 600 hospitals, focusing on access, revenue, and payment optimization for long-term success |
160 |
| 53 |
T-Systems North Americat-systems.com
A global ICT provider for multinational corporations and public sector institutions, focusing on diversity, innovation, and team collaboration in their corporate culture |
157 |
| 54 |
Downers Grove South High Schoolcsd99.org
A prominent high school in Downers Grove with a rich tradition of excellence in academics, performing arts, athletics, and activities for over 50 years |
154 |
| 55 |
GO2 Partnersgo2partners.com
A diverse team of marketing and operations experts providing tailored solutions for global companies, leveraging expertise, technology, and sustainable practices |
152 |
| 56 |
Green Grassgreengrasslandscape.com
A top landscape architecture and construction firm in Downers Grove, IL, offering residential and commercial design, construction, maintenance, and snow plowing services in Chicagoland |
148 |
| 57 |
Rexnord Aerospaceaerospace.rexnord.com
A global supplier of specialized bearings, seals, gears, and electrical components for the aerospace industry, ensuring smooth operation and reliability |
110 |
| 58 |
Straight Northstraightnorth.com
Internet marketing agency driving online sales leads and e-commerce revenue for growth-minded firms through SEO, PPC, display ads, email marketing, and responsive websites |
110 |
| 59 |
SEASPARseaspar.org
SEASPAR provides dynamic programs and quality recreation services for people with disabilities in twelve community service areas, focusing on abilities and realizing dreams |
100 |
| 60 |
AZ CFSstgusa.com
A leading logistics provider in the US, offering comprehensive services like warehousing, distribution, transportation, and value-added solutions to shipping and distribution industries |
70 |
| 61 |
Honey-Jam Cafehoneyjamcafe.com
Cozy neighborhood gathering place serving various breakfast and lunch items like omelettes, pancakes, and sandwiches alongside house-brewed drinks and extensive event catering services. |
49 |
| 62 |
True North Logistics
A small business offering complete warehouse management services including operations, maintenance, system implementation, inventory management, optimization, and staffing solutions with experienced team |
16 |
| 63 |
Maveriq Technologymaveriqtech.com
The company specializes in providing high-quality Cloud Integration, Data Migration Services, and SAP project implementation for businesses in the US |
9 |
| 64 |
Galvao Otoni Internal Medicine @ VCA Arboretum View Animal Hopsitalgointernalmedicine.com
The company is dedicated to improving pet health by providing education and training to veterinarians specializing in internal medicine |
7 |
| 65 |
RML Norway Builders Incnorwaybuilt.com
A family-run remodeling company in Chicagoland specializing in kitchen, bath, and basement renovations, as well as three season rooms and handyman services |
4 |
| 66 |
Tall Ridgetallridge.com
Full-service eCommerce provider specializing in strategic growth for top brands, with expertise in Amazon, Walmart, and other marketplaces |
4 |
| 67 |
eusu Intermodal
eusu Intermodal, Inc offers comprehensive third party logistics solutions, including intermodal, highway brokerage, international freight, and specialized services across North America |
2 |
Turn this list into pipeline
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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 Oct 24, 2026.
The same list elsewhere in United States
- The largest companies in the United States 91,669
- The largest companies in California 12,813
- The largest companies in New York State 10,485
- The largest companies in Texas 8,086
- The largest companies in Florida 4,945
- The largest companies in Illinois 4,175
- The largest companies in Pennsylvania 3,110
- The largest companies in Massachusetts 3,093
- The largest companies in Georgia 2,632
- The largest companies in Ohio 2,618
- The largest companies in New Jersey 2,569
- The largest companies in Virginia 2,503
- The largest companies in Michigan 2,346
- The largest companies in North Carolina 2,174
- The largest companies in Alabama 1,806
- The largest companies in Washington State 1,785
- The largest companies in Colorado 1,774
- The largest companies in Minnesota 1,700
- The largest companies in Maryland 1,527
- The largest companies in Wisconsin 1,482
- The largest companies in New York 6,920
- The largest companies in San Francisco 2,030
- The largest companies in Houston 1,791
- The largest companies in Chicago 1,668