These companies in Essonne are primarily engaged in IT services, consulting, and software development. They range from mid-sized firms to established companies, with the largest, APIXIT, employing 303 people. Other significant firms include G4, specializing in information management, NBTECH, focused on engineering services, and INTERDATA, providing expertise in IT networks and security.
A notable pattern among these companies is their geographical concentration. Many are headquartered in a few key municipalities within Essonne, such as Les Ulis, Massy, and Bièvres. This suggests a localized cluster of IT and engineering expertise within the department.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 | 303 | ||||
| 2 | 254 | ||||
| 3 | 244 | ||||
| 4 |
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 | |||
| 5 |
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 | |||
| 6 |
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 | |||
| 7 | 181 | ||||
| 8 |
APILOG Automationapilog.com
Specialized in industrial and commercial automation integration, part of a larger group with expertise in civil engineering and construction, serving SMEs |
115 | |||
| 9 |
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 | |||
| 10 |
EBS Group Franceebsgroup.fr
Provides comprehensive IT services and equipment management, offering tailored software and hardware solutions to small and medium businesses. |
88 | |||
| 11 |
MOJOVIDAmojovida.fr
Specializing in point of sale information systems for distribution and restaurant chains, providing expertise in optimizing operations and customer service |
74 | |||
| 12 |
SOLUTYS Groupsolutys.com
Specializes in automatic identification, network and cybersecurity solutions, offering comprehensive products and services to large companies and SMEs. |
65 | |||
| 13 |
IPSILAN NETWORKSipsilan-networks.fr
Integration of network and telecom solutions with strong technical expertise, client partnership, and proactive business development for tailored support. |
58 | |||
| 14 |
IBSibs-cloud.fr
Global IT provider offering a wide range of services, including maintenance, IT management, and cybersecurity Experienced teams ensure personalized support for optimal system security and performance |
52 | |||
| 15 |
PROTECTICprotectic.fr
Engineering company, intervening in large-scale industrial projects (aeronautics, space, defense, energy, transport). Accompanying major industrial players in product development. |
50 | |||
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 |
Elecom SASelecom.fr
French manufacturer of interactive solutions such as touch screens, kiosks, and digital applications Official Samsung partner delivering tailored solutions for events and businesses |
46 | |||
| 17 |
Junior CentraleSupélecjuniorcs.fr
Junior CentraleSupélec is a student-run consulting firm offering services in digital, electronics, strategy, data analytics, and environment sectors with over 4500 future engineering graduates |
42 | |||
| 18 |
Cyriascyrias.com
Consulting and integration company specializes in assisting Purchasing and Finance Departments with implementing Cloud Solutions, offering expertise in digital transformation projects |
42 | |||
| 19 | 41 | ||||
| 20 |
EZYTAILezytail.com
Industrial supply chain management providing back office software, mutualized logistics, transportation solutions, ERP integration, and consulting for new and existing multi-channel retailing businesses. |
41 | |||
| 21 |
NirWananirwana.fr
The company offers complete and highly customizable telephone systems, comprehensive IT solutions, network cabling, and tailored industrial servers and testing benches |
41 | |||
| 22 |
ERT Intégration - Groupe Kardolkardol.fr
A subsidiary of KARDOL Group, specializing in SAP BUSINESS ONE integration for small to medium-sized businesses with expertise in industry, after-sales service, and trade |
40 | |||
| 23 | 39 | ||||
| 24 |
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 | |||
| 25 | 34 | ||||
| 26 |
M2iinformatique-m2i.fr
Provides network installation, cloud services with Office 365, business applications, and security systems for companies and individuals. |
33 | |||
| 27 |
ANANASananas.bio
A company specializing in audiovisual and networking solutions for businesses, government, education, and retail spaces, offering high-quality products and expert advice |
29 | |||
| 28 |
Aryason Consultingaryason.fr
Massy based firm specialized in providing professional advice on computer systems and software solutions with seven years of industry experience. |
26 | |||
| 29 |
GPLExpertgplexpert.com
Specializing in healthcare IT, offering services and solutions to optimize information systems, manage projects, drive digital transformation, and ensure data security and system availability |
25 | |||
| 30 |
CPP-SYSTEM
A consulting and IT service company operating in Madagascar and France, specialized in digital payment, customer loyalty, and management solutions Coming soon! |
24 | |||
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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 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
- Professional services firms in the Essonne department 68
- Public sector organisations in the Essonne department 66
- Aerospace and defence companies in the Essonne department 65
- 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
- IT services companies in France 5,000
- IT services companies in Île-de-France 2,624
- IT services companies in the Hauts-de-Seine department 737
- IT services companies in Auvergne-Rhône-Alpes 519
- IT services companies in the Rhône department 286
- IT services companies in Occitanie 280
- IT services companies in Provence-Alpes-Côte d'Azur 268
- IT services companies in Grand Est 248
- IT services companies in Hauts-de-France 236
- IT services companies in Pays de la Loire 205
- IT services companies in Nouvelle-Aquitaine 194
- IT services companies in the Nord department 170
- IT services companies in the Haute-Garonne department 158
- IT services companies in the Bouches-du-Rhône department 155
- IT services companies in the Loire-Atlantique department 130
- IT services companies in the Yvelines department 121
- IT services companies in Brittany 113
- IT services companies in the Val-de-Marne department 101
- IT services companies in the Gironde department 99
- IT services companies in Paris 1,386
- IT services companies in Lyon 171
- IT services companies in Boulogne-Billancourt 125
- IT services companies in Toulouse 119
- IT services companies in Levallois-Perret 94