# The 30 largest IT services companies in the Ille-et-Vilaine department

Tamtam tracks 65 IT services companies headquartered in the Ille-et-Vilaine department. This list ranks the 30 largest by number of employees on LinkedIn, led by SIB [numérique, santé et secteur public], RBI and OET. Their median headcount is 64. Half of them were founded in 2002 or later. The most common headquarters are Rennes (13), Cesson-Sévigné (5) and Saint-Grégoire (2).

These companies in Ille-et-Vilaine are primarily IT services and consulting firms, ranging from mid-sized companies to smaller, specialized enterprises. Notable examples include SIB, a cooperative in digital health and public sector IT, and RBI, which focuses on information system design and integration. OET specializes in industrial automation and robotics, while Hexatel supports businesses with telecommunications and network solutions. Groupe Creative assists clients with IT and digital transformation projects, and BLUE provides high-speed network and data hosting services.

The data shows a strong concentration of these companies in Rennes, with many others located in nearby towns such as Pacé, Betton, and Saint-Grégoire. The founding dates indicate a mix of established firms, like Hexatel (1946) and OET (1975), and more recently established companies, such as LIKSI (2017) and Ovalt (2017), suggesting ongoing development in the region's IT and industrial sectors.

🇫🇷 Ille-et-Vilaine · 30 companies · Updated Nov 12, 2026

| # | Company | Industry | Headquarters | Employees | Founded |
|---|---|---|---|---|---|
| 1 | [SIB \[numérique, santé et secteur public\]](https://www.tamtam.ai/c/sib-numerique-sante-et-secteur-public) (sib.fr)<br>Innovative cooperative in digital health and public sector, serving 620+ institutions in modernizing their IT systems with a wide range of services and expertise | IT Services and IT Consulting | 🇫🇷 Rennes | 499 | 1993 |
| 2 | [RBI](https://www.tamtam.ai/c/rbi-rennes) (rbi-informatique.fr)<br>Specializing in information systems design, implementation, and integration, RBI-Informatique offers services in infrastructure, collaboration, and management solutions for businesses | IT Services and IT Consulting | 🇫🇷 Rennes | 468 | 1981 |
| 3 | [OET](https://www.tamtam.ai/c/oet-betton) (groupe-ovalt.com)<br>Independent service company specializing in MES, automation, robotics, electrical systems, and weighing with turnkey solutions and maintenance across multiple sites. | Automation Machinery Manufacturing | 🇫🇷 Betton | 266 | 1975 |
| 4 | [Hexatel](https://www.tamtam.ai/c/hexatel) (hexatel.fr)<br>Support for businesses and communities in telecom, networks, and IT with personalized, high-quality, and carefully selected technology solutions. | Telecommunications | 🇫🇷 Noyal-sur-Vilaine | 257 | 1946 |
| 5 | [Groupe Creative](https://www.tamtam.ai/c/groupe-creative) (groupe-creative.fr)<br>Works with clients on IT and digital transformation projects, offering expertise in consulting, creation, development, research, and innovation across various digital domains. | IT Services and IT Consulting | 🇫🇷 Rennes | 232 | 2008 |
| 6 | [BLUE](https://www.tamtam.ai/c/blue) (bt-blue.com)<br>For over 15 years, this company specializes in providing high-speed network, data hosting, and unified communication solutions to professionals in a secure environment | IT System Data Services | 🇫🇷 Châteaubourg | 216 | 2005 |
| 7 | [Sodifrance](https://www.tamtam.ai/c/sodifrance) (sodifrance.fr)<br>Provides technology consulting, digital transformation, data management, application and infrastructure services to enhance organizational competitiveness and collaboration. | IT Services and IT Consulting | 🇫🇷 Saint-Grégoire | 172 | 1986 |
| 8 | [TALENDI](https://www.tamtam.ai/c/talendi) (talendi.com)<br>A social enterprise offering industrial and digital services, employing over 550 people, including 420 with disabilities, with expertise in various fields like assembly and logistics | Motor Vehicle Parts Manufacturing | 🇫🇷 Rennes | 137 | 1975 |
| 9 | [Adventiel](https://www.tamtam.ai/c/adventiel) (adventiel.fr)<br>Adventiel is a specialized consultancy firm assisting agricultural and food industries in transitioning to sustainable models through customized digital solutions | Software Development | 🇫🇷 Pacé | 107 |  |
| 10 | [6TM](https://www.tamtam.ai/c/6tm) (6tm.com)<br>6TM supports clients in achieving effective communication through web, mobile, and software solutions, with services ranging from e-commerce to custom development and e-tourism | IT Services and IT Consulting | 🇫🇷 Rennes | 100 | 1998 |
| 11 | [UNIXO](https://www.tamtam.ai/c/unixo) (unixo.fr)<br>UNIXO specializes in providing innovative and personalized IT solutions for SMEs, ETIs & local authorities, including telecommunications integration, IT management, and broadband internet services | Telecommunications | 🇫🇷 Rennes | 90 |  |
| 12 | [CYIM](https://www.tamtam.ai/c/cyim) (cyim.com)<br>A company specializing in IT and audiovisual services for medical societies, offering digital solutions for medical congresses and associations | IT Services and IT Consulting | 🇫🇷 Rennes | 88 | 2001 |
| 13 | [Ovalt](https://www.tamtam.ai/c/ovalt) (groupe-ovalt.com)<br>Group of expert subsidiaries providing digital transformation services and solutions to modernize factories and support Industry 4.0 initiatives. | Industrial Machinery Manufacturing | 🇫🇷 Betton | 77 | 2017 |
| 14 | [LIKSI](https://www.tamtam.ai/c/liksi) (liksi.fr)<br>LIKSI is a software development company in Rennes and Nantes, offering high-quality services with expertise in open source technologies and agile project teams | IT Services and IT Consulting | 🇫🇷 Rennes | 64 | 2017 |
| 15 | [Groupe A2COM](https://www.tamtam.ai/c/groupe-a2com) (a2com.fr)<br>A2COM Group supports healthcare organizations in digital evolution with innovative solutions to simplify access to technology and improve medical services efficiency | IT Services and IT Consulting | 🇫🇷 Pacé | 64 |  |
| 16 | [AJP - Groupe Factoria](https://www.tamtam.ai/c/ajp-groupe-factoria) (ajp.fr)<br>Specialized in workplace technologies for over 30 years, offering printing equipment, IT solutions, document digitalization, telephony, cloud services, audiovisual, and office space design | IT Services and IT Consulting | 🇫🇷 Cesson-Sévigné | 59 | 1991 |
| 17 | [Digitalis](https://www.tamtam.ai/c/digitalis) (digitalis.fr)<br>Digitalis specializes in providing custom, user-friendly audiovisual solutions to enhance workspaces, focusing on innovation, simplicity, and productivity for businesses and institutions | IT Services and IT Consulting | 🇫🇷 Cesson-Sévigné | 51 | 2016 |
| 18 | [Provectio](https://www.tamtam.ai/c/provectio) (provectio.fr)<br>IT services provider offering IT management, security, cloud computing, telecommunications, and network availability for businesses, providing support, strategy, and technical expertise | Telecommunications | 🇫🇷 Rennes | 48 | 2004 |
| 19 | [Oxxeo](https://www.tamtam.ai/c/oxxeo) (oxxeo.fr)<br>A human-sized IT consulting company in Rennes, specializing in digital transformation with a focus on App Engineering, DevOps, Cloud, and Project Management They prioritize employee well-being and career growth | IT Services and IT Consulting | 🇫🇷 Cesson-Sévigné | 46 | 2017 |
| 20 | [DaNSO](https://www.tamtam.ai/c/danso) (danso.fr)<br>Provides outsourced network and application performance management solutions integrating observability and security for large enterprises and telecom operators. | Information Services | 🇫🇷 Cesson-Sévigné | 46 | 2019 |
| 21 | [Groupe Pandora](https://www.tamtam.ai/c/groupe-pandora) (groupe-pandora.com)<br>Support for telecom and IT projects across northern France, offering technical expertise, personalized services, and strong team collaboration. | Telecommunications | 🇫🇷 Rennes | 42 | 2011 |
| 22 | [SpikeeLabs](https://www.tamtam.ai/c/spikeelabs) (spikeelabs.fr)<br>SpikeeLabs provides information system design, development, integration, and support services with a focus on growth, innovation, and strong human values | IT Services and IT Consulting | 🇫🇷 Rennes | 38 | 2016 |
| 23 | [MAX Digital Services](https://www.tamtam.ai/c/max-digital-services) (maxds.fr)<br>MAX DS is a digital services company focused on a collaborative model, prioritizing human values to provide high-quality consulting, software engineering, testing, and project management services | IT Services and IT Consulting | 🇫🇷 Rennes | 34 | 2016 |
| 24 | [Cognix Systems](https://www.tamtam.ai/c/cognix-systems) (cognix-systems.com)<br>Consulting, designing, and developing websites, advanced web applications, and software with a focus on ergonomic, high-value web portals. | Technology, Information and Internet | 🇫🇷 Rennes | 34 | 2002 |
| 25 | [OGI Groupe](https://www.tamtam.ai/c/ogi-groupe) (ogi-groupe.fr)<br>OGI provides successful IT project implementation and management services to companies of all sizes and sectors, offering expertise in software deployment and infrastructure setup | IT Services and IT Consulting | 🇫🇷 Chartres-de-Bretagne | 33 | 2000 |
| 26 | [Synergiz](https://www.tamtam.ai/c/synergiz) (synergiz.com)<br>Provides intuitive, connected, and interactive solutions, specializing in Mixed Reality. Supports businesses with XR projects from start to finish including hardware, software, and custom development. | IT Services and IT Consulting | 🇫🇷 Saint-Malo | 32 | 2011 |
| 27 | [SEMAPHORS](https://www.tamtam.ai/c/semaphors) (semaphors.com)<br>Established in 1996, specializing in healthcare sector Providing quality IT services, software solutions, telephony, and medical devices for healthcare professionals in the western region | IT Services and IT Consulting | 🇫🇷 Saint-Grégoire | 30 | 1996 |
| 28 | [Abelium Entreprises](https://www.tamtam.ai/c/abelium-entreprises) (informatique-logiciel-bretagne.com)<br>A reliable and proactive IT partner providing quality services tailored to clients' needs, with a focus on innovation, technical expertise, and customer support | IT Services and IT Consulting | 🇫🇷 Saint-Malo | 28 | 1999 |
| 29 | [RETIS Connected Solutions](https://www.tamtam.ai/c/retis-connected-solutions) (apixit.fr)<br>Specialized engineers design, deploy, and maintain network and security solutions with 24/7 hotline support for customer infrastructure supervision. | Computer Networking Products | 🇫🇷 Montauban-de-Bretagne | 27 | 1993 |
| 30 | [Ouest Consulting IP3G](https://www.tamtam.ai/c/ouest-consulting-ip3g) (ouest-consulting.net)<br>OUEST CONSULTING IP3G specializes in infrastructure development and management, integrating cutting-edge IT, networking, and telecom technologies for businesses and local governments in Western France | IT Services and IT Consulting | 🇫🇷 Cesson-Sévigné | 26 |  |

## 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 12, 2026.

## More company lists in the Ille-et-Vilaine department

- [The largest companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/largest-companies-ille-et-vilaine) (1,454)
- [Companies with in-house R&D in the Ille-et-Vilaine department](https://www.tamtam.ai/l/r-and-d-companies-ille-et-vilaine) (152)
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- [Manufacturers in the Ille-et-Vilaine department](https://www.tamtam.ai/l/manufacturers-ille-et-vilaine) (100)
- [Professional services firms in the Ille-et-Vilaine department](https://www.tamtam.ai/l/professional-services-firms-ille-et-vilaine) (94)
- [SaaS companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/saas-companies-ille-et-vilaine) (85)
- [Family-owned companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/family-owned-companies-ille-et-vilaine) (81)
- [Software Development companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/software-development-companies-ille-et-vilaine) (80)
- [Public sector organisations in the Ille-et-Vilaine department](https://www.tamtam.ai/l/public-sector-organisations-ille-et-vilaine) (75)
- [IT Services and IT Consulting companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/it-services-and-it-consulting-companies-ille-et-vilaine) (67)
- [Hardware manufacturers in the Ille-et-Vilaine department](https://www.tamtam.ai/l/hardware-companies-ille-et-vilaine) (61)
- [Education providers in the Ille-et-Vilaine department](https://www.tamtam.ai/l/education-companies-ille-et-vilaine) (60)
- [Distributors and wholesalers in the Ille-et-Vilaine department](https://www.tamtam.ai/l/distributors-and-wholesalers-ille-et-vilaine) (58)
- [Consulting firms in the Ille-et-Vilaine department](https://www.tamtam.ai/l/consulting-firms-ille-et-vilaine) (54)
- [Food and Beverage Manufacturing companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/food-and-beverage-manufacturing-companies-ille-et-vilaine) (46)
- [Retail companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/retail-companies-ille-et-vilaine) (46)
- [Critical infrastructure operators in the Ille-et-Vilaine department](https://www.tamtam.ai/l/critical-infrastructure-operators-ille-et-vilaine) (45)
- [Financial services firms in the Ille-et-Vilaine department](https://www.tamtam.ai/l/financial-services-firms-ille-et-vilaine) (45)
- [Subscription businesses in the Ille-et-Vilaine department](https://www.tamtam.ai/l/subscription-businesses-ille-et-vilaine) (45)
- [Construction companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/construction-companies-ille-et-vilaine) (43)
- [Law Practice companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/law-practice-companies-ille-et-vilaine) (43)
- [Higher Education companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/higher-education-companies-ille-et-vilaine) (41)
- [Legal Services companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/legal-services-companies-ille-et-vilaine) (41)

## The same list elsewhere in France

- [IT services companies in France](https://www.tamtam.ai/l/it-services-companies-france) (5,000)
- [IT services companies in Île-de-France](https://www.tamtam.ai/l/it-services-companies-ile-de-france) (2,624)
- [IT services companies in the Hauts-de-Seine department](https://www.tamtam.ai/l/it-services-companies-hauts-de-seine) (737)
- [IT services companies in Auvergne-Rhône-Alpes](https://www.tamtam.ai/l/it-services-companies-auvergne-rhone-alpes) (519)
- [IT services companies in the Rhône department](https://www.tamtam.ai/l/it-services-companies-rhone) (286)
- [IT services companies in Occitanie](https://www.tamtam.ai/l/it-services-companies-occitanie) (280)
- [IT services companies in Provence-Alpes-Côte d'Azur](https://www.tamtam.ai/l/it-services-companies-provence-alpes-cote-dazur) (268)
- [IT services companies in Grand Est](https://www.tamtam.ai/l/it-services-companies-grand-est) (248)
- [IT services companies in Hauts-de-France](https://www.tamtam.ai/l/it-services-companies-hauts-de-france) (236)
- [IT services companies in Pays de la Loire](https://www.tamtam.ai/l/it-services-companies-pays-de-la-loire) (205)
- [IT services companies in Nouvelle-Aquitaine](https://www.tamtam.ai/l/it-services-companies-nouvelle-aquitaine) (194)
- [IT services companies in the Nord department](https://www.tamtam.ai/l/it-services-companies-nord) (170)
- [IT services companies in the Haute-Garonne department](https://www.tamtam.ai/l/it-services-companies-haute-garonne) (158)
- [IT services companies in the Bouches-du-Rhône department](https://www.tamtam.ai/l/it-services-companies-bouches-du-rhone) (155)
- [IT services companies in the Loire-Atlantique department](https://www.tamtam.ai/l/it-services-companies-loire-atlantique) (130)
- [IT services companies in the Yvelines department](https://www.tamtam.ai/l/it-services-companies-yvelines) (121)
- [IT services companies in Brittany](https://www.tamtam.ai/l/it-services-companies-brittany) (113)
- [IT services companies in the Val-de-Marne department](https://www.tamtam.ai/l/it-services-companies-val-de-marne) (101)
- [IT services companies in the Gironde department](https://www.tamtam.ai/l/it-services-companies-gironde) (99)
- [IT services companies in Paris](https://www.tamtam.ai/l/it-services-companies-paris) (1,386)
- [IT services companies in Lyon](https://www.tamtam.ai/l/it-services-companies-lyon) (171)
- [IT services companies in Boulogne-Billancourt](https://www.tamtam.ai/l/it-services-companies-boulogne-billancourt) (125)
- [IT services companies in Toulouse](https://www.tamtam.ai/l/it-services-companies-toulouse) (119)
- [IT services companies in Levallois-Perret](https://www.tamtam.ai/l/it-services-companies-levallois-perret) (94)

## The same list elsewhere

- [IT services companies in the world](https://www.tamtam.ai/l/it-services-companies-in-the-world) (20,934)
- [IT services companies in Europe](https://www.tamtam.ai/l/it-services-companies-in-europe) (11,376)

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Source: https://www.tamtam.ai/l/it-services-companies-ille-et-vilaine