> Enrich.chat gives AI agents verified work emails and mobiles. To use it from an agent, read https://enrich.chat/agents.md . This is the Markdown version of https://enrich.chat/naics/621111/illinois/ # NAICS 621111 companies in Illinois Companies with NAICS code 621111 (Offices of Physicians (Except Mental Health Specialists)) headquartered in Illinois, with their cities, sizes and SIC codes. By Enrich.chat Editorial. Updated October 22, 2026. **Short answer:** The biggest NAICS 621111 companies in Illinois by headcount range include Springfield Clinic, Christie Clinic and Midwest Orthopaedics At Rush. NAICS 621111 is the code for Offices of Physicians (Except Mental Health Specialists). Among those counted, they are mostly very small: 65% have 50 or fewer employees. ## Which NAICS 621111 companies are in Illinois? The biggest by headcount range include Springfield Clinic, Christie Clinic, Midwest Orthopaedics At Rush, Physicians Immediate Care and Skincure Oncology. NAICS 621111 is the code for Offices of Physicians (Except Mental Health Specialists). Names link to a company profile where we have one. | Company | City | Employees | | --- | --- | --- | | Springfield Clinic | Springfield | 1,001 to 5,000 | | Christie Clinic | Champaign | 1,001 to 5,000 | | Midwest Orthopaedics At Rush | Chicago | 501 to 1,000 | | Physicians Immediate Care | Rosemont | 501 to 1,000 | | Skincure Oncology | Burr Ridge | 501 to 1,000 | | Aunt Martha's Health & Wellness | Olympia Fields | 501 to 1,000 | | Midwest Vision Partners | Chicago | 501 to 1,000 | | Pcc Community Wellness Center | Oak Park | 501 to 1,000 | | Uropartners | Des Plaines | 201 to 500 | | Esperanza Health Centers | Chicago | 201 to 500 | | Chicago Family Health Center | Chicago | 201 to 500 | | Derick Dermatology | Elgin | 201 to 500 | | Barrington Orthopedic Specialists | Schaumburg | 201 to 500 | | Vitalskin Dermatology | Urbana | 51 to 200 | | Kovach Eye Institute | Elmhurst | 51 to 200 | | Advanced Dermatology | Lincolnshire | 51 to 200 | | Illinois Retina Associates | Harvey | 51 to 200 | | Pediatrics On Demand | Oak Lawn | 51 to 200 | | Illinois Dermatology Institute | Oak Brook | 51 to 200 | | Northwest Neurology | Lake Barrington | 51 to 200 | | Parkview Orthopaedic Group | Palos Heights | 51 to 200 | | Bright Light Medical Imaging | Elk Grove Village | 51 to 200 | | Lake Forest Pediatric Associates | Lake Bluff | 51 to 200 | | Rockford Gastroenterology Associates | Rockford | 51 to 200 | | The Wright Center For Women's Health | Naperville | 51 to 200 | The table shows the 25 biggest by headcount range, with ties broken by audience size. The charts and percentages below cover every company counted for this page, not just these 25, and companies with fewer than 11 employees are not counted. Headquarters is the location on each company's public profile. ## Which cities in Illinois? Within Illinois, Chicago (17%), Naperville (4%) and Oak Brook (4%) are the most common headquarters. **Figure: Cities of NAICS 621111 companies in Illinois.** Bars for the share of counted NAICS 621111 companies in Illinois headquartered in each city: Chicago 17%, Naperville 4%, Oak Brook 4%, Oak Lawn 4%, Rockford 4%, Schaumburg 4%. *Share of counted NAICS 621111 companies in Illinois by headquarters city.* ## How big are they? 65% of the NAICS 621111 companies counted in Illinois have 50 or fewer employees, and the middle one is in the 11 to 50 range. Companies with fewer than 11 employees are not counted. **Figure: Size of NAICS 621111 companies in Illinois.** Seven columns for the share of counted NAICS 621111 companies in Illinois in each employee range: 11 to 50 65%, 51 to 200 20%, 201 to 500 6%, 501 to 1,000 7%, 1,001 to 5,000 2%, 5,001 to 10,000 0%, 10,001+ 0%. *Share of counted NAICS 621111 companies in Illinois in each employee range.* ## How do you reach the people at these Illinois companies? The people to talk to are usually operations, IT and finance leaders. Build the list in three prompts to your AI agent. ### 1. Count them (free) Counting who matches never uses credits. ```text Use www.enrich.chat to count the companies with NAICS code 621111 in Illinois ``` ### 2. Find the people (5 credits per person) Name the roles you sell to. Each person returned is 5 credits, and name, title and company are included. ```text Use www.enrich.chat to find the operations, IT and finance leaders at companies with NAICS code 621111 in Illinois, with their titles ``` ### 3. Get their work emails (10 credits each) An email is 10 credits only when one is found. Every email comes with a status: verified, catch-all or unknown. ```text Use www.enrich.chat to find the work emails for these people and tell me which ones are verified ``` ## More to explore About the code: [NAICS 621111: Offices of Physicians (Except Mental Health Specialists)](https://enrich.chat/naics/621111/). About the place: [companies in Illinois](https://enrich.chat/companies-in/illinois/). NAICS 621111 in other states: [Texas](https://enrich.chat/naics/621111/texas/)[California](https://enrich.chat/naics/621111/california/)[Florida](https://enrich.chat/naics/621111/florida/)[New York](https://enrich.chat/naics/621111/new-york/)[Georgia](https://enrich.chat/naics/621111/georgia/)[Tennessee](https://enrich.chat/naics/621111/tennessee/)[New Jersey](https://enrich.chat/naics/621111/new-jersey/)[Ohio](https://enrich.chat/naics/621111/ohio/)[Arizona](https://enrich.chat/naics/621111/arizona/)[Massachusetts](https://enrich.chat/naics/621111/massachusetts/) Other NAICS codes in Illinois: [NAICS 541511: Custom Computer Programming Services](https://enrich.chat/naics/541511/illinois/)[NAICS 541512: Computer Systems Design Services](https://enrich.chat/naics/541512/illinois/)[NAICS 722511: Full-Service Restaurants](https://enrich.chat/naics/722511/illinois/)[NAICS 531210: Offices of Real Estate Agents](https://enrich.chat/naics/531210/illinois/)[NAICS 524210: Insurance Agencies and Brokerages](https://enrich.chat/naics/524210/illinois/)[NAICS 541613: Marketing Consulting Services](https://enrich.chat/naics/541613/illinois/)[NAICS 488510: Freight Transportation Arrangement](https://enrich.chat/naics/488510/illinois/)[NAICS 238220: Plumbing, Heating, and Air-Conditioning](https://enrich.chat/naics/238220/illinois/)[NAICS 236220: Commercial and Institutional Building](https://enrich.chat/naics/236220/illinois/)[NAICS 621999: All Other Miscellaneous Ambulatory](https://enrich.chat/naics/621999/illinois/) ## Frequently asked questions ### Which NAICS 621111 companies are in Illinois? The biggest by headcount range include Springfield Clinic, Christie Clinic, Midwest Orthopaedics At Rush, Physicians Immediate Care and Skincure Oncology. The page lists 25 with links to their profiles where we have them. ### What is NAICS 621111? NAICS 621111 is the code for Offices of Physicians (Except Mental Health Specialists), in sector 62: Health Care and Social Assistance. ### Which cities in Illinois have the most? Chicago (17%), Naperville (4%) and Oak Brook (4%) lead among the companies counted. ## Try this prompt Find the people at NAICS 621111 companies in Illinois ```text Use www.enrich.chat to find the operations, IT and finance leaders at companies with NAICS code 621111 in Illinois, with titles and verified work emails ``` ## Related - [Companies using a technology](https://enrich.chat/companies-using/) - [NAICS 621111 in Texas](https://enrich.chat/naics/621111/texas/) - [NAICS 621111 in California](https://enrich.chat/naics/621111/california/) - [NAICS 621111 in Florida](https://enrich.chat/naics/621111/florida/) - [NAICS 621111 in New York](https://enrich.chat/naics/621111/new-york/) - [NAICS 541511 in Illinois](https://enrich.chat/naics/541511/illinois/) - [NAICS 541512 in Illinois](https://enrich.chat/naics/541512/illinois/) - [NAICS 722511 in Illinois](https://enrich.chat/naics/722511/illinois/) - [NAICS 531210 in Illinois](https://enrich.chat/naics/531210/illinois/) - [Tech stack lookup](https://enrich.chat/tools/tech-stack-lookup/)