These Chicago-based professional services firms are predominantly large companies, many with a global presence. They offer a diverse range of expertise, from real estate and accounting to IT consulting and legal services. Notable companies include JLL, a real estate and investment management specialist, and RSM US LLP, which provides assurance, tax, and consulting services. Also present are Thoughtworks, a global technology consultancy, and Baker McKenzie, a law practice offering practical legal advice.
A significant concentration of these firms operates in the accounting and business consulting sectors, indicating a strong professional services hub in Chicago. Several of these large organizations, such as Cushman & Wakefield and Crowe, were founded in the early to mid-20th century, highlighting a long-standing tradition of professional services in the city.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 | 104,899 | ||||
| 2 |
Cushman & Wakefieldcushmanwakefield.com
Global commercial real estate services provider with 52,000 professionals focused on advancing client, colleague, and community outcomes worldwide. |
53,000 | |||
| 3 |
RSM US LLPrsmus.com
Provider of assurance, tax, and consulting services focused on middle market clients with a global presence and professional development culture. |
19,700 | |||
| 4 |
HUB Internationalhubinternational.com
Advises businesses and individuals on insurance, risk management, employee benefits, retirement, and wealth management with tailored solutions. |
16,129 | |||
| 5 |
Thoughtworksthoughtworks.com
A global technology consultancy specializing in strategy, design, and engineering to drive digital innovation, fostering diverse talent and a strong cultivation culture |
12,735 | |||
| 6 |
Baker McKenziebakermckenzie.com
Provide practical legal advice combining local knowledge and international expertise to help businesses succeed across global markets. |
11,895 | |||
| 7 |
Grant Thornton (US)grantthornton.com
Provides independent audit, tax, and advisory services through a global network, focusing on quality, trust, and strong client relationships. |
11,518 | |||
| 8 | 11,182 | ||||
| 9 |
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 | |||
| 10 | 9,411 | ||||
| 11 |
Kirkland & Elliskirkland.com
Providing top-tier legal services in corporate transactions, litigation, investigations, and asset management with global reach and innovative approach. |
8,683 | |||
| 12 |
Kearneykearney.com
Global consulting firm with a focus on people, strategic operations, and building the future through teamwork and hands-on expertise in over 40 countries |
7,559 | |||
| 13 |
Leo Burnettleoburnett.com
Global communications agency combining creativity, data, and technology to influence human behavior and drive client prosperity worldwide. |
6,825 | |||
| 14 |
Huronhuronconsultinggroup.com
A global professional services firm specializing in strategy creation, operations optimization, digital transformation, and empowering businesses for sustainable results |
6,453 | |||
| 15 |
Accenture Strategy & Consultingaccenture.com
Combines deep industry expertise with advanced analytics and human-led design methodologies to help global clients act with speed and confidence throughout operations. |
6,217 | |||
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. | |||||
| 16 |
Sidley Austin LLPsidley.com
Providing comprehensive legal services worldwide, specializing in complex transactions, restructuring, investigations, regulatory, and litigation matters across multiple industries. |
5,113 | |||
| 17 |
Mayer Brownmayerbrown.com
Representation of major corporations, funds, and financial institutions in complex transactions and disputes across international markets. |
4,544 | |||
| 18 |
Sargent & Lundysargentlundy.com
A global leader in architect engineering specializing in power, energy, and decarbonization, offering comprehensive project services to public and private clients |
4,511 | |||
| 19 | 4,223 | ||||
| 20 |
Spencer Stuartspencerstuart.com
Specializes in senior executive search, board recruitment, leadership advisory, succession planning, and organizational effectiveness for diverse global clients. |
3,609 | |||
| 21 |
Chartischartis.com
Consulting firm specializing in healthcare strategy, transformation, and operational models to improve affordability, accessibility, safety, and patient experience. |
3,598 | |||
| 22 |
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 | |||
| 23 |
Perkins&Willperkinswill.com
Design and architecture firm creating healthy, beautiful spaces worldwide with expertise in architecture, interior design, urban and landscape planning. |
3,060 | |||
| 24 |
Staff Management | SMXstaffmanagement.com
A leader in workforce solutions for fulfillment, distribution, and manufacturing industries, specializing in Onsite Workforce Management and Recruitment and Placement Solutions |
3,025 | |||
| 25 |
Intelliasintellias.com
Trusted technology partner accelerating sustainable digitalization for top-tier organizations, delivering mission-critical projects and measurable outcomes for clients globally |
2,955 | |||
| 26 |
Credicocredico.com
A leading customer acquisition agency connecting brands with local sales teams to acquire new customers through face-to-face methods |
2,779 | |||
| 27 |
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 | |||
| 28 |
Heidrick & Strugglesheidrick.com
Providing executive search, leadership consulting, and corporate culture services to global Fortune 1000 companies for improved performance. |
2,477 | |||
| 29 |
West Monroewestmonroe.com
Global consulting firm specializing in business and technology solutions, focusing on rapid impact through industry, strategy, and people integration. |
2,416 | |||
| 30 |
Sikichsikich.com
A global professional services company specializing in technology solutions, delivering transformative digital strategies and financial services to various clients worldwide |
2,335 | |||
Turn this list into pipeline
Tamtam finds the decision-makers at every company on a list like this one, with verified emails, phone numbers and the buying signals that tell you when to reach out.
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 Chicago
- The largest companies in Chicago 1,860
- Multinational companies in Chicago 366
- Financial services firms in Chicago 212
- Financial Services companies in Chicago 185
- Education providers in Chicago 138
- SaaS companies in Chicago 132
- Consulting firms in Chicago 127
- IT Services and IT Consulting companies in Chicago 115
- IT services companies in Chicago 114
- Venture capital and private equity firms in Chicago 106
- AI companies in Chicago 100
- Hospitals and Health Care companies in Chicago 99
- Software Development companies in Chicago 97
- Manufacturers in Chicago 97
- Companies with in-house R&D in Chicago 93
- Subscription businesses in Chicago 92
- Healthcare providers in Chicago 86
- Retail chains in Chicago 84
- Companies with a mobile app in Chicago 75
- Critical infrastructure operators in Chicago 74
- Publicly traded companies in Chicago 71
- Real Estate companies in Chicago 67
- Non-profit Organizations companies in Chicago 66
- Corporate groups and holding companies in Chicago 64
The same list elsewhere in United States
- Professional services firms in the United States 7,078
- Professional services firms in New York State 955
- Professional services firms in California 880
- Professional services firms in Texas 629
- Professional services firms in Florida 375
- Professional services firms in Virginia 344
- Professional services firms in Illinois 339
- Professional services firms in Massachusetts 249
- Professional services firms in New Jersey 249
- Professional services firms in Georgia 246
- Professional services firms in Pennsylvania 245
- Professional services firms in Ohio 195
- Professional services firms in Maryland 176
- Professional services firms in Michigan 172
- Professional services firms in Washington State 163
- Professional services firms in North Carolina 142
- Professional services firms in Alabama 135
- Professional services firms in Minnesota 125
- Professional services firms in New York 735
- Professional services firms in Houston 156
- Professional services firms in Atlanta 143
- Professional services firms in San Francisco 130
- Professional services firms in Washington 109
- Professional services firms in Los Angeles 108