# 50 leading professional services firms in Brittany

Tamtam tracks 167 professional services firms headquartered in Brittany. This list ranks the 50 largest by number of employees on LinkedIn, led by Groupe SAMSIC, Keyrus and Interaction Interim. Their median headcount is 192. Half of them were founded in 1986 or later. The most common headquarters are Rennes (13), Cesson-Sévigné (3) and Brest (2).

The professional services firms in Brittany include a mix of business consulting, IT services, and accounting firms. Groupe SAMSIC offers tailored solutions in facility management and HR services. Keyrus focuses on reliable intelligence foundations and performance steering. Interaction Interim provides temporary work and recruitment services. Groupe Cogedis offers accounting, management, legal, and HR consultancy.

Several companies in the list, such as Groupe SAMSIC, Interaction Interim, and RBI, are based in Rennes or nearby Cesson-Sévigné, indicating a cluster of professional services activity in this area. ABER Propreté and NET PLUS specialize in cleaning and facilities services.

🇫🇷 Brittany · 50 companies · Updated Nov 11, 2026

| # | Company | Industry | Headquarters | Employees | Founded |
|---|---|---|---|---|---|
| 1 | [Groupe SAMSIC](https://www.tamtam.ai/c/groupe-samsic) (samsic.com)<br>With over 30 years of experience, we prioritize human and professional values while offering tailored solutions in facility management and HR services | Business Consulting and Services | 🇫🇷 Cesson-Sévigné | 6,680 | 1986 |
| 2 | [Keyrus](https://www.tamtam.ai/c/keyrus) (keyrus.com)<br>Architects reliable intelligence foundations, human-in-command governance, and performance steering to operationalize intelligence for adaptive, resilient, continuously improving organizations. | IT Services and IT Consulting | 🇫🇷 Levallois-Perret | 2,020 | 1996 |
| 3 | [Interaction Interim](https://www.tamtam.ai/c/interaction-interim) (interaction-interim.com)<br>National network providing temporary work, recruitment for fixed-term and permanent contracts, training, support, and consulting services across all business sectors. | Staffing and Recruiting | 🇫🇷 Rennes | 1,055 | 1991 |
| 4 | [Groupe Cogedis - Comptabilité et conseil aux entreprises](https://www.tamtam.ai/c/groupe-cogedis-comptabilite-et-conseil-aux-entreprises) (cogedis.com)<br>Providing accounting, management, legal, and human resources consultancy services alongside strategic wealth management and environmental advice for professionals and agricultural business owners. | Accounting | 🇫🇷 Saint-Thonan | 783 | 1970 |
| 5 | [ABER Propreté](https://www.tamtam.ai/c/aber-proprete) (aberproprete.fr)<br>Providing high-quality industrial cleaning and hygiene services with continuous employee training and precise service monitoring since 1975. | Environmental Services | 🇫🇷 Saint-Jacques-de-la-Lande | 682 | 1975 |
| 6 | [NET PLUS](https://www.tamtam.ai/c/net-plus) (net-plus.fr)<br>A company specializing in cleaning services, prioritizing customer satisfaction, quality interventions, and social responsibility with a focus on employee well-being and respect | Facilities Services | 🇫🇷 Cesson-Sévigné | 521 | 1990 |
| 7 | [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 |
| 8 | [Ouest Conseils](https://www.tamtam.ai/c/ouest-conseils) (ouestconseils.bzh)<br>Providing accounting, audit, and strategic management consulting for Breton businesses, managing payroll and digital transition to ensure client success and local growth. | Accounting | 🇫🇷 Quimper | 450 | 1988 |
| 9 | [Office Notarial Anastasia Moreau](https://www.tamtam.ai/c/office-notarial-anastasia-moreau) (moreau-fougeres.notaires.fr)<br>Located in the heart of Fougères, this company offers legal services in real estate, family, and corporate law, focusing on accessibility, listening, and modernity | Legal Services | 🇫🇷 Fougères | 447 |  |
| 10 | [LMCO](https://www.tamtam.ai/c/lmco) (lmco.fr)<br>provides up-to-date information and resources on business law, fiscal policies, social regulations, and commercial real estate for companies | Construction | 🇫🇷 Langueux | 402 |  |
| 11 | [Cerfrance Côtes d'Armor](https://www.tamtam.ai/c/cerfrance-cotes-d-armor) (cerfrance22.fr)<br>Leading accounting and consulting firm providing strategic support, financial expertise, and social management services for small businesses, farmers, artisans, and independent professionals. | Accounting | 🇫🇷 Plérin | 313 | 1955 |
| 12 | [Geirec](https://www.tamtam.ai/c/geirec) (geirec.com)<br>An independent regional cabinet with a national focus, GEIREC supports businesses with expertise and values, offering daily partnership, confidentiality, competence, and responsiveness | Accounting | 🇫🇷 Rennes | 308 | 1979 |
| 13 | [SPC](https://www.tamtam.ai/c/spc-parthenay-de-bretagne) (servicepro-bretagne.com)<br>This company specializes in industrial automation and robotics, supporting integrators and manufacturers in their projects with expert guidance. | Automation Machinery Manufacturing | 🇫🇷 Parthenay-de-Bretagne | 277 | 2016 |
| 14 | [CAPEOS](https://www.tamtam.ai/c/capeos-rennes) (capeos.fr)<br>Provides comprehensive accounting, legal, and tax services alongside audit, wealth management, and IT solutions for companies across diverse sectors through local offices. | Accounting | 🇫🇷 Rennes | 266 | 1979 |
| 15 | [Igam Expertise Comptable](https://www.tamtam.ai/c/igam-expertise-comptable) (igam.fr)<br>Accounting and advisory network serving 6000 clients across various sectors with 35 offices and 300 professionals in western France. | Accounting | 🇫🇷 Lamballe | 266 | 1986 |
| 16 | [VIRAGE CONSEIL](https://www.tamtam.ai/c/virage-conseil) (virageconseil.com)<br>Specializes in business development, sales growth, professional training, and commercial animation with a strong presence in telemarketing and merchandising. | International Trade and Development | 🇫🇷 | 262 | 1993 |
| 17 | [QUARTA](https://www.tamtam.ai/c/quarta) (quarta.fr)<br>Precision measurement and 3D modeling for urban and rural spaces Creating high value projects through expertise in surveying, urban engineering, and VRD design | Civil Engineering | 🇫🇷 Saint Jacques de la Lande | 259 | 1982 |
| 18 | [SCC Raising Places' Values](https://www.tamtam.ai/c/scc-raising-places-values) (scc.fr)<br>Manages, transforms, and invents unique living spaces, focusing on strategic and operational services to increase the value of properties for clients and partners. | Leasing Non-residential Real Estate | 🇫🇷 Paris | 233 | 1962 |
| 19 | [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 |
| 20 | [Intérim Emploi Service](https://www.tamtam.ai/c/interim-emploi-service) (interim-emploi-service.fr)<br>A company in Rennes offering temporary work, job placements, and professional development while prioritizing employee skills, safety, diversity, and discrimination prevention | Staffing and Recruiting | 🇫🇷 Saint-Grégoire | 228 | 2005 |
| 21 | [Axys Consultants](https://www.tamtam.ai/c/axys-consultants) (axys-consultants.com)<br>Management consultancy providing digital transformation, data analytics, and operational excellence services across procurement, finance, marketing, and sales departments for large international corporate clients. | Business Consulting and Services | 🇫🇷 Levallois Perret | 227 | 1987 |
| 22 | [Cerfrance Finistère](https://www.tamtam.ai/c/cerfrance-finistere) (finistere.cerfrance.fr)<br>Accounting and consulting firm providing services to businesses and their leaders in Finistère, specializing in advice and expertise in accounting | Accounting | 🇫🇷 Quimper | 216 |  |
| 23 | [Aqualeha](https://www.tamtam.ai/c/aqualeha) (aqualeha.com)<br>The company offers a range of services to prevent food, safety, and environmental risks for the protection of assets and individuals | Biotechnology Research | 🇫🇷 Vitré | 216 | 1984 |
| 24 | [Icoopa](https://www.tamtam.ai/c/icoopa) (icoopa.bzh)<br>ICOOPA is a management and accounting association founded in 1977, serving over 5,000 members in agriculture, crafts, and trade sectors in Brittany, France | Accounting | 🇫🇷 Morlaix | 195 | 1977 |
| 25 | [Groupe SECOB](https://www.tamtam.ai/c/groupe-secob) (secob.fr)<br>Provides accounting, payroll, and audit services supporting over 3500 companies in creation, development, and business transfer phases. | Business Consulting and Services | 🇫🇷 Cesson-Sévigné | 192 | 1963 |
| 26 | [Groupe Interaction](https://www.tamtam.ai/c/groupe-interaction) (interaction-groupe.com)<br>This company facilitates employment access, offering temp agencies, recruitment firms, specialized services, digital solutions, and a training center for diverse job seekers. | Staffing and Recruiting | 🇫🇷 Rennes | 178 | 1991 |
| 27 | [Arkéa Investment Services](https://www.tamtam.ai/c/arkea-investment-services) (arkea-is.com)<br>Asset management company combining financial and extra-financial performance, offering diverse investment solutions for individual and institutional clients. | Financial Services | 🇫🇷 | 171 | 1980 |
| 28 | [Lavance](https://www.tamtam.ai/c/lavance) (lavance.com)<br>Provider of vehicle washing equipment and services including high-pressure centers, tunnels, water recycling, financing, maintenance, and station operation support. | Automation Machinery Manufacturing | 🇫🇷 Le Rheu | 168 | 1979 |
| 29 | [METI](https://www.tamtam.ai/c/meti) (cgi.com)<br>Specializing in business process management solutions for retail, this software development company provides services and support to major clients worldwide | IT Services and IT Consulting | 🇫🇷 Larmor-Plage | 166 | 1982 |
| 30 | [isatech](https://www.tamtam.ai/c/isatech) (isatech.fr)<br>International IT solutions provider specializing in ERP & CRM solutions, Microsoft Dynamics 365 expertise, BI, Azure, and professional services for various industry sectors worldwide | IT Services and IT Consulting | 🇫🇷 Vannes | 158 | 1983 |
| 31 | [Groupe Asten](https://www.tamtam.ai/c/groupe-asten) (groupe-asten.fr)<br>A company specializing in digital transformation, offering hosting, cybersecurity, custom software development, retail solutions, and consulting with a focus on Brittany's growth | IT Services and IT Consulting | 🇫🇷 Gouesnou | 150 | 1995 |
| 32 | [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 |
| 33 | [OJC Conseil](https://www.tamtam.ai/c/ojc-conseil) (ojc-consulting.com)<br>This consulting firm offers IT services for purchase, sales, and treasury management Specializing in IT transformation projects with expertise in IVALUA solutions | Software Development | 🇫🇷 Vannes | 135 | 2007 |
| 34 | [E&C Expertise Comptable](https://www.tamtam.ai/c/e-and-c-expertise-comptable) (by-ec.fr)<br>Independent accounting and collaborative services firm providing expertise in various areas such as accounting, business advisory, legal counseling, payroll, and administration support | Accounting | 🇫🇷 Brest | 127 | 1979 |
| 35 | [In Extenso Bretagne](https://www.tamtam.ai/c/in-extenso-bretagne) (inextenso.fr)<br>A major player in accounting and consulting for small and medium-sized businesses, offering support in all areas of business management | Accounting | 🇫🇷 Brest | 125 | 1991 |
| 36 | [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 |  |
| 37 | [Pros-Consulte](https://www.tamtam.ai/c/pros-consulte) (pros-consulte.com)<br>Supports organizations in preventing psychosocial risks, enhancing mental health, and fostering well-being at work, improving collective performance and employee engagement. | Human Resources Services | 🇫🇷 Lorient | 101 | 2009 |
| 38 | [Tourny Meyer](https://www.tamtam.ai/c/tourny-meyer) (tournymeyer.fr)<br>Offers business real estate consulting, sales, and leasing services for offices, warehouses, retail, hotels, and urban developments across multiple French cities. | Real Estate | 🇫🇷 Rennes | 101 | 1990 |
| 39 | [TALENZ TOADENN](https://www.tamtam.ai/c/talenz-toadenn) (talenz.fr)<br>Multidisciplinary consulting firm supporting entrepreneurs and business leaders with strategy, finance, compliance, audit, legal, HR, and technology solutions. | Business Consulting and Services | 🇫🇷 Rennes | 92 |  |
| 40 | [ADENT](https://www.tamtam.ai/c/adent) (adentingenierie.com)<br>Designing sustainable and adaptable agri-food factories that are both thoughtful and harmonious in their construction and operation | Construction | 🇫🇷 Rennes | 92 | 2006 |
| 41 | [APAVE REGION BRETAGNE-MAINE](https://www.tamtam.ai/c/apave-region-bretagne-maine) (apave.com)<br>Apave provides comprehensive risk management services to companies and communities worldwide, aiming to increase safety, protect the environment, and optimize organizational performance | Environmental Services | 🇫🇷 Le Rheu | 89 | 1867 |
| 42 | [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 |
| 43 | [Happy to meet you](https://www.tamtam.ai/c/happy-to-meet-you) (happytomeetyou.fr)<br>Provides human resources and communication expertise to companies, focusing on executive recruitment and HR consulting, including organizational transformation, development, and skill assessments. | Human Resources Services | 🇫🇷 Rennes | 71 | 2016 |
| 44 | [Excelis Conseil](https://www.tamtam.ai/c/excelis-conseil) (excelis-conseil.fr)<br>Accounting and audit firm with 75 professionals and 6 partners in Rennes and Vannes Serving 1,500+ clients in the Grand Ouest region | Accounting | 🇫🇷 Pacé | 70 | 2003 |
| 45 | [IFOPSE](https://www.tamtam.ai/c/ifopse) (ifopse.com)<br>Specializing in safety training and consulting for nearly 40 years, the company helps manage personnel safety in areas such as fire, chemical, and crisis management | Professional Training and Coaching | 🇫🇷 Nivillac | 70 | 1983 |
| 46 | [L'Optimiste le Groupe](https://www.tamtam.ai/c/l-optimiste-le-groupe) (loptimiste.fr)<br>Collective of experts providing strategy, accounting, HR, legal, financing, and CSR support to over 1,500 SMEs in France. | Accounting | 🇫🇷 Rennes | 68 | 2016 |
| 47 | [COMPTAGESMA](https://www.tamtam.ai/c/comptagesma) (comptagesma.com)<br>Comptagesma guides entrepreneurs from company creation to accounting, tax optimization, and strategic advice, with a focus on proximity, technology, and social responsibility | Accounting | 🇫🇷 Saint-Malo | 67 | 1979 |
| 48 | [SAPIENCE AUDIT Cabinet de commissariat aux comptes](https://www.tamtam.ai/c/sapience-audit-cabinet-de-commissariat-aux-comptes) (aac-ec.com)<br>An independent accounting and consulting firm providing tailored support and strategic advice to business owners in Pays de Lorient | Accounting | 🇫🇷 Ploemeur | 63 | 1989 |
| 49 | [Télémaque](https://www.tamtam.ai/c/telemaque) (telemaque-penelope.nous-recrutons.fr)<br>A leading call center company in France offering services such as lead generation, telemarketing, appointment setting, sales, and customer support with extensive training and growth opportunities | Telephone Call Centers | 🇫🇷 Caudan | 60 |  |
| 50 | [Cabinet BOURGOIS - Groupe MERLIN](https://www.tamtam.ai/c/cabinet-bourgois-groupe-merlin) (cabinet-merlin.fr)<br>A recognized player in environmental consulting and engineering for over 80 years, based in Betton, France, as a subsidiary of Groupe MERLIN | Environmental Services | 🇫🇷 Betton | 53 | 1938 |

## 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 Brittany

- [The largest companies in Brittany](https://www.tamtam.ai/l/largest-companies-brittany) (3,058)
- [Companies with in-house R&D in Brittany](https://www.tamtam.ai/l/r-and-d-companies-brittany) (366)
- [Retail chains in Brittany](https://www.tamtam.ai/l/retail-chains-brittany) (344)
- [Manufacturers in Brittany](https://www.tamtam.ai/l/manufacturers-brittany) (307)
- [Multinational companies in Brittany](https://www.tamtam.ai/l/multinational-companies-brittany) (264)
- [Family-owned companies in Brittany](https://www.tamtam.ai/l/family-owned-companies-brittany) (201)
- [Food and Beverage Manufacturing companies in Brittany](https://www.tamtam.ai/l/food-and-beverage-manufacturing-companies-brittany) (182)
- [Public sector organisations in Brittany](https://www.tamtam.ai/l/public-sector-organisations-brittany) (165)
- [Hardware manufacturers in Brittany](https://www.tamtam.ai/l/hardware-companies-brittany) (148)
- [Distributors and wholesalers in Brittany](https://www.tamtam.ai/l/distributors-and-wholesalers-brittany) (145)
- [Software Development companies in Brittany](https://www.tamtam.ai/l/software-development-companies-brittany) (132)
- [Food and beverage companies in Brittany](https://www.tamtam.ai/l/food-and-beverage-companies-brittany) (130)
- [SaaS companies in Brittany](https://www.tamtam.ai/l/saas-companies-brittany) (128)
- [Critical infrastructure operators in Brittany](https://www.tamtam.ai/l/critical-infrastructure-operators-brittany) (120)
- [Consumer goods companies in Brittany](https://www.tamtam.ai/l/consumer-goods-companies-brittany) (115)
- [IT services companies in Brittany](https://www.tamtam.ai/l/it-services-companies-brittany) (113)
- [Education providers in Brittany](https://www.tamtam.ai/l/education-companies-brittany) (112)
- [Agriculture companies in Brittany](https://www.tamtam.ai/l/agriculture-companies-brittany) (108)
- [Retail companies in Brittany](https://www.tamtam.ai/l/retail-companies-brittany) (107)
- [IT Services and IT Consulting companies in Brittany](https://www.tamtam.ai/l/it-services-and-it-consulting-companies-brittany) (101)
- [Consulting firms in Brittany](https://www.tamtam.ai/l/consulting-firms-brittany) (99)
- [Healthcare providers in Brittany](https://www.tamtam.ai/l/healthcare-providers-brittany) (97)
- [Contract manufacturers in Brittany](https://www.tamtam.ai/l/contract-manufacturers-brittany) (93)
- [Construction companies in Brittany](https://www.tamtam.ai/l/construction-companies-brittany) (92)

## The same list elsewhere in France

- [Professional services firms in France](https://www.tamtam.ai/l/professional-services-firms-france) (6,611)
- [Professional services firms in Île-de-France](https://www.tamtam.ai/l/professional-services-firms-ile-de-france) (3,377)
- [Professional services firms in Auvergne-Rhône-Alpes](https://www.tamtam.ai/l/professional-services-firms-auvergne-rhone-alpes) (711)
- [Professional services firms in the Hauts-de-Seine department](https://www.tamtam.ai/l/professional-services-firms-hauts-de-seine) (629)
- [Professional services firms in Provence-Alpes-Côte d'Azur](https://www.tamtam.ai/l/professional-services-firms-provence-alpes-cote-dazur) (433)
- [Professional services firms in the Rhône department](https://www.tamtam.ai/l/professional-services-firms-rhone) (400)
- [Professional services firms in Occitanie](https://www.tamtam.ai/l/professional-services-firms-occitanie) (399)
- [Professional services firms in Grand Est](https://www.tamtam.ai/l/professional-services-firms-grand-est) (316)
- [Professional services firms in Nouvelle-Aquitaine](https://www.tamtam.ai/l/professional-services-firms-nouvelle-aquitaine) (308)
- [Professional services firms in Hauts-de-France](https://www.tamtam.ai/l/professional-services-firms-hauts-de-france) (260)
- [Professional services firms in Pays de la Loire](https://www.tamtam.ai/l/professional-services-firms-pays-de-la-loire) (254)
- [Professional services firms in the Bouches-du-Rhône department](https://www.tamtam.ai/l/professional-services-firms-bouches-du-rhone) (249)
- [Professional services firms in the Haute-Garonne department](https://www.tamtam.ai/l/professional-services-firms-haute-garonne) (208)
- [Professional services firms in the Nord department](https://www.tamtam.ai/l/professional-services-firms-nord) (178)
- [Professional services firms in the Loire-Atlantique department](https://www.tamtam.ai/l/professional-services-firms-loire-atlantique) (158)
- [Professional services firms in the Gironde department](https://www.tamtam.ai/l/professional-services-firms-gironde) (151)
- [Professional services firms in Normandy](https://www.tamtam.ai/l/professional-services-firms-normandy) (114)
- [Professional services firms in the Yvelines department](https://www.tamtam.ai/l/professional-services-firms-yvelines) (108)
- [Professional services firms in the Ille-et-Vilaine department](https://www.tamtam.ai/l/professional-services-firms-ille-et-vilaine) (94)
- [Professional services firms in Paris](https://www.tamtam.ai/l/professional-services-firms-paris) (2,241)
- [Professional services firms in Lyon](https://www.tamtam.ai/l/professional-services-firms-lyon) (265)
- [Professional services firms in Toulouse](https://www.tamtam.ai/l/professional-services-firms-toulouse) (139)
- [Professional services firms in Marseille](https://www.tamtam.ai/l/professional-services-firms-marseille) (123)
- [Professional services firms in Boulogne-Billancourt](https://www.tamtam.ai/l/professional-services-firms-boulogne-billancourt) (102)

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Source: https://www.tamtam.ai/l/professional-services-firms-brittany