> 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/541511/illinois/ # NAICS 541511 companies in Illinois Companies with NAICS code 541511 (Custom Computer Programming Services) headquartered in Illinois, with their cities, sizes and SIC codes. By Enrich.chat Editorial. Updated October 22, 2026. **Short answer:** The biggest NAICS 541511 companies in Illinois by headcount range include Thoughtworks Holding, Syndigo and Numeric Technologies. NAICS 541511 is the code for Custom Computer Programming Services. Among those counted, they are mostly small: 78% have 200 or fewer employees. ## Which NAICS 541511 companies are in Illinois? The biggest by headcount range include Thoughtworks Holding, Syndigo, Numeric Technologies, Royal Cyber and Q1 Technologies. NAICS 541511 is the code for Custom Computer Programming Services. Names link to a company profile where we have one. | Company | City | Employees | | --- | --- | --- | | [Thoughtworks Holding](https://enrich.chat/company/thoughtworks-holding/) | Chicago | 10,001+ | | Syndigo | Chicago | 1,001 to 5,000 | | Numeric Technologies | Warrenville | 1,001 to 5,000 | | Royal Cyber | Naperville | 1,001 to 5,000 | | Q1 Technologies | Chicago | 1,001 to 5,000 | | Vistex | Hoffman Estates | 1,001 to 5,000 | | Bitwise | Schaumburg | 1,001 to 5,000 | | Quinnox | Chicago | 1,001 to 5,000 | | Halo Branded Solutions | Sterling | 1,001 to 5,000 | | Keeper Security | Chicago | 501 to 1,000 | | Copado | Chicago | 501 to 1,000 | | Viva Usa | Rolling Meadows | 501 to 1,000 | | Litera | Chicago | 501 to 1,000 | | Ameex Technologies | Schaumburg | 501 to 1,000 | | Springml | Chicago | 501 to 1,000 | | Cybertech Systems And Software | Oak Brook | 501 to 1,000 | | Teletrac Navman | Northbrook | 501 to 1,000 | | Coreflex Solutions | Naperville | 501 to 1,000 | | Katalyst Software Services | Evanston | 501 to 1,000 | | Dynamic Enterprise Solutions | Rolling Meadows | 501 to 1,000 | | Metmox | Schaumburg | 501 to 1,000 | | York Solutions | Westchester | 201 to 500 | | Codal | Chicago | 201 to 500 | | Dscout | Chicago | 201 to 500 | | Uptake | Chicago | 201 to 500 | 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 (44%), Naperville (6%) and Schaumburg (6%) are the most common headquarters. **Figure: Cities of NAICS 541511 companies in Illinois.** Bars for the share of counted NAICS 541511 companies in Illinois headquartered in each city: Chicago 44%, Naperville 6%, Schaumburg 6%, Northbrook 2%, Warrenville 2%. *Share of counted NAICS 541511 companies in Illinois by headquarters city.* ## How big are they? 47% of the NAICS 541511 companies counted in Illinois have 50 or fewer employees, and the middle one is in the 51 to 200 range. Companies with fewer than 11 employees are not counted. **Figure: Size of NAICS 541511 companies in Illinois.** Seven columns for the share of counted NAICS 541511 companies in Illinois in each employee range: 11 to 50 47%, 51 to 200 31%, 201 to 500 12%, 501 to 1,000 6%, 1,001 to 5,000 4%, 5,001 to 10,000 0%, 10,001+ 0%. *Share of counted NAICS 541511 companies in Illinois in each employee range.* ## How old are they? Most were founded in the 2010s (49%), then the 2000s (27%). **Figure: When NAICS 541511 companies in Illinois were founded.** Eight columns for the share of counted NAICS 541511 companies in Illinois founded in each era: Before 1960 1%, 1960s 1%, 1970s 1%, 1980s 4%, 1990s 16%, 2000s 27%, 2010s 49%, 2020s 2%. *Share of counted NAICS 541511 companies in Illinois by the era they were founded in, for the ones that list a founding year.* ## How do you reach the people at these Illinois companies? The people to talk to are usually engineering, delivery and revenue 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 541511 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 engineering, delivery and revenue leaders at companies with NAICS code 541511 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 541511: Custom Computer Programming Services](https://enrich.chat/naics/541511/). About the place: [companies in Illinois](https://enrich.chat/companies-in/illinois/). NAICS 541511 in other states: [California](https://enrich.chat/naics/541511/california/)[Texas](https://enrich.chat/naics/541511/texas/)[New York](https://enrich.chat/naics/541511/new-york/)[Florida](https://enrich.chat/naics/541511/florida/)[Virginia](https://enrich.chat/naics/541511/virginia/)[New Jersey](https://enrich.chat/naics/541511/new-jersey/)[Massachusetts](https://enrich.chat/naics/541511/massachusetts/)[Georgia](https://enrich.chat/naics/541511/georgia/)[Washington](https://enrich.chat/naics/541511/washington/)[Pennsylvania](https://enrich.chat/naics/541511/pennsylvania/) Other NAICS codes in 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 621111: Offices of Physicians](https://enrich.chat/naics/621111/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 541511 companies are in Illinois? The biggest by headcount range include Thoughtworks Holding, Syndigo, Numeric Technologies, Royal Cyber and Q1 Technologies. The page lists 25 with links to their profiles where we have them. ### What is NAICS 541511? NAICS 541511 is the code for Custom Computer Programming Services, in sector 54: Professional, Scientific, and Technical Services. ### Which cities in Illinois have the most? Chicago (44%), Naperville (6%) and Schaumburg (6%) lead among the companies counted. ## Try this prompt Find the people at NAICS 541511 companies in Illinois ```text Use www.enrich.chat to find the engineering, delivery and revenue leaders at companies with NAICS code 541511 in Illinois, with titles and verified work emails ``` ## Related - [Companies using a technology](https://enrich.chat/companies-using/) - [NAICS 541511 in California](https://enrich.chat/naics/541511/california/) - [NAICS 541511 in Texas](https://enrich.chat/naics/541511/texas/) - [NAICS 541511 in New York](https://enrich.chat/naics/541511/new-york/) - [NAICS 541511 in Florida](https://enrich.chat/naics/541511/florida/) - [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/) - [NAICS 524210 in Illinois](https://enrich.chat/naics/524210/illinois/) - [Tech stack lookup](https://enrich.chat/tools/tech-stack-lookup/)