These are professional services firms in Essonne, predominantly mid-sized companies with a strong presence in IT services and engineering. UTAC, with 1249 employees, specializes in advancing the mobility industry towards a safer and cleaner future. NOVELTY provides technical support for events, while KS SERVICES offers tailored logistics and general services. APIXIT focuses on cybersecurity, infrastructure, and cloud solutions.
The companies are concentrated in towns like Les Ulis, Orsay, and Massy. Several firms, such as NBTECH and ADVANCE Engineering, specialize in engineering services for sectors like automotive, aerospace, and nuclear. There is also a notable cluster of IT services and consulting companies, including DSI GROUP, IJNEXT, and INTERDATA.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 | 1,249 | ||||
| 2 |
NOVELTYnovelty.fr
Specialist in technical support for event industries, offering services like audiovisual equipment rental, engineering, sales, installation, and maintenance of audiovisual systems |
835 | |||
| 3 |
KS SERVICESks-services.com
Provides tailored logistics, general services, security, and administrative support through on-site teams committed to operational excellence and continuous process improvement results. |
501 | |||
| 4 | 303 | ||||
| 5 | 244 | ||||
| 6 |
DSI GROUPgroup-dsi.com
An engineering services company within the DSI GROUP, prioritizing staff development and customer relationships with a focus on flexibility and customer loyalty |
225 | |||
| 7 |
COMEARTHcomearth-france.com
An agile and custom B2B and B2C customer relationship outsourcing center in France, dedicated to delivering quality services for a memorable customer experience |
214 | |||
| 8 |
ADVANCE Engineeringadvance-eng.fr
ADVANCE Engineering, a subsidiary of CERAP Pr茅vention, specializes in providing technical engineering services for complex projects in the nuclear sector |
205 | |||
| 9 |
IJNEXTijnext.com
A major player in IT infrastructure services and innovative technologies, offering comprehensive solutions in security, performance, and automation through three interconnected companies |
202 | |||
| 10 |
INTERDATAinterdata.fr
French company providing certified expertise in IT networks, SI security, and observability for over 40 years Offering tailored services for reliable, scalable, and secure network management |
188 | |||
| 11 |
ORANO DS- DEMANTELEMENT ET SERVICES
A utilities company in France specializing in dismantling and services related to nuclear energy and waste management |
177 | |||
| 12 |
AVL in Franceavl.com
Develops, simulates, and tests engines, transmissions, powertrains, and batteries. Provides turnkey test and simulation solutions, software, instrumentation, and services for the mobility industry. |
162 | |||
| 13 |
Stem Groupestemgroupe.fr
Specializing in providing cleaning and facility management services to businesses and public institutions, including maintenance, security, landscaping, and pest control |
144 | |||
| 14 |
Exatechglobal.exatech-group.com
Collaboration with universities and agencies to optimize and secure paper-based and digital examinations and assessments through innovative technology solutions. |
114 | |||
| 15 |
KYOCERA Document Solutions Francekyoceradocumentsolutions.fr
Provide comprehensive document management solutions including software, hardware, and professional services to support digital transformation and reduce environmental impact. |
113 | |||
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 |
EBS Group Franceebsgroup.fr
Provides comprehensive IT services and equipment management, offering tailored software and hardware solutions to small and medium businesses. |
88 | |||
| 17 |
SOLUTYS Groupsolutys.com
Specializes in automatic identification, network and cybersecurity solutions, offering comprehensive products and services to large companies and SMEs. |
65 | |||
| 18 |
NUCLETUDESnucletudes.ariane.group
Specialized in engineering and testing for protection against severe radiative and electromagnetic aggressions, as a subsidiary of a global aerospace company |
61 | |||
| 19 |
IPSILAN NETWORKSipsilan-networks.fr
Integration of network and telecom solutions with strong technical expertise, client partnership, and proactive business development for tailored support. |
58 | |||
| 20 |
PROTECTICprotectic.fr
Engineering company, intervening in large-scale industrial projects (aeronautics, space, defense, energy, transport). Accompanying major industrial players in product development. |
50 | |||
| 21 |
SOL CONSEILvertical-sea.com
Geotechnical consulting firm with over 35 years of experience offering services such as soil investigation, foundation design, and project management |
43 | |||
| 22 |
Cyriascyrias.com
Consulting and integration company specializes in assisting Purchasing and Finance Departments with implementing Cloud Solutions, offering expertise in digital transformation projects |
42 | |||
| 23 | 41 | ||||
| 24 | 39 | ||||
| 25 |
CREATYM Francecreatym-france.com
Specialized in engineering services, technical consulting, and studies for industrial actors, prioritizing human-centric approach, teamwork, and passion for technology to enhance client services |
36 | |||
| 26 | 34 | ||||
| 27 |
CONSTRUIREconstruire-sa.fr
The company provides engineering services for various industries, offering expertise in developing innovative solutions and technical support |
31 | |||
| 28 |
IDETEC Environnementsites.google.com
IDETEC Environment is a leading player in monitoring engineering, providing services from network diagnostics to site supervision, with a focus on quality and accreditation |
30 | |||
| 29 |
Ad Consultingad-consulting.paris
An independent consulting firm specializing in finance, professional and real estate loans, and wealth management for professionals and self-employed professionals |
27 | |||
| 30 |
Aryason Consultingaryason.fr
Massy based firm specialized in providing professional advice on computer systems and software solutions with seven years of industry experience. |
26 | |||
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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 the Essonne department
- The largest companies in the Essonne department 1,149
- Companies with in-house R&D in the Essonne department 198
- Multinational companies in the Essonne department 156
- Manufacturers in the Essonne department 127
- Hardware manufacturers in the Essonne department 114
- Distributors and wholesalers in the Essonne department 76
- IT Services and IT Consulting companies in the Essonne department 70
- Public sector organisations in the Essonne department 66
- Aerospace and defence companies in the Essonne department 65
- IT services companies in the Essonne department 60
- Retail chains in the Essonne department 59
- Construction companies in the Essonne department 56
- Software Development companies in the Essonne department 51
- Pharmaceutical companies in the Essonne department 45
- Electronics and semiconductor companies in the Essonne department 44
- Research institutes in the Essonne department 42
- Events Services companies in the Essonne department 41
- SaaS companies in the Essonne department 41
- Consulting firms in the Essonne department 40
- Family-owned companies in the Essonne department 38
- Contract manufacturers in the Essonne department 35
- Research Services companies in the Essonne department 35
- Critical infrastructure operators in the Essonne department 32
- Education providers in the Essonne department 30
The same list elsewhere in France
- Professional services firms in France 6,611
- Professional services firms in 脦le-de-France 3,377
- Professional services firms in Auvergne-Rh么ne-Alpes 711
- Professional services firms in the Hauts-de-Seine department 629
- Professional services firms in Provence-Alpes-C么te d'Azur 433
- Professional services firms in the Rh么ne department 400
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- Professional services firms in the Bouches-du-Rh么ne department 249
- Professional services firms in the Haute-Garonne department 208
- Professional services firms in the Nord department 178
- Professional services firms in Brittany 167
- Professional services firms in the Loire-Atlantique department 158
- Professional services firms in the Gironde department 151
- Professional services firms in Normandy 114
- Professional services firms in the Yvelines department 108
- Professional services firms in Paris 2,241
- Professional services firms in Lyon 265
- Professional services firms in Toulouse 139
- Professional services firms in Marseille 123
- Professional services firms in Boulogne-Billancourt 102