These Yvelines-based companies specialize in environmental services, civil engineering, and public administration. They range from established firms like SEPUR, focusing on waste management since 1965, and CULLIGAN FRANCE, a water treatment specialist, to newer entities such as Demcy, founded in 2021 for asbestos removal and demolition, and Grand Paris Seine & Oise, managing urban and rural development.
A notable pattern is the strong presence of environmental services, with companies like IGIENAIR, active in indoor air quality, and STEREAU, providing water treatment engineering. Guyancourt appears as a common headquarters location, hosting Egis en France and Ecologic France.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 | 937 | ||||
| 2 |
CULLIGAN FRANCEculligan.fr
Specialist in water treatment providing softeners, purifiers, and water fountains for homes, businesses, and communities ensuring quality water. |
862 | |||
| 3 |
Grand Paris Seine & Oisegpseo.fr
management of a large urban and rural territory focusing on economic sectors, innovation, infrastructure, environment, and public services organization |
429 | |||
| 4 |
Egis en Franceegis-group.com
International consulting, construction engineering, and mobility services company. Designs and operates smart infrastructure and buildings addressing climate challenges for balanced and sustainable territorial development. |
349 | |||
| 5 |
Riva Acierrivaacier.com
Over 45 years experience, seven industrial sites in France, leading steel long products manufacturer and largest scrap metal recycler in France. |
312 | |||
| 6 |
IGIENAIRigienair.com
Specializing in Indoor Air Quality, IGIENAIR offers services for air purification and control, along with monitoring tools for commercial spaces worldwide |
272 | |||
| 7 |
Bouygues Construction Expertises Nucléaires
Offers integrated, innovative, high-value solutions globally, covering all technical fields and the complete life cycle of nuclear infrastructure, including engineering, maintenance, and dismantling. |
254 | |||
| 8 |
CTP environnement groupctp-environnement.com
Innovative company specializing in technical industrial cleaning, heat exchanger treatment, sludge, and liquid effluent treatment with multiple branches worldwide |
195 | |||
| 9 |
Demcyeiffage-demcy.com
A company specializing in asbestos removal and demolition of buildings and infrastructure, offering selective equipment removal, material recycling, and nationwide presence |
159 | |||
| 10 |
STEREAU
The company specializes in engineering solutions for water treatment, focusing on efficiency, performance, innovation, and sustainability to preserve water resources for future generations |
154 | |||
| 11 |
Ecologic Franceecologic-france.com
Manages prevention, collection, and recycling of end-of-life electrical/electronic equipment, sports/leisure items, and DIY/gardening tools, fostering a circular economy. |
147 | |||
| 12 | 140 | ||||
| 13 |
SOINS MODERNES DES ARBRES SMDAsmda-sas.com
Specialized in ecological maintenance and management of parks and gardens, serving private clients and public authorities nationwide with environmental respect. |
131 | |||
| 14 |
Printerre Groupeprinterre.fr
Specialized in IT asset disposal, data erasure, equipment reconditioning, consumable remanufacturing, and distribution, promoting digital decarbonation and employment inclusion. |
86 | |||
| 15 |
CASGBS - Communauté d'agglomération Saint Germain Boucles de Seinesaintgermainbouclesdeseine.fr
Join a dynamic intercommunal organization near Paris, dedicated to innovation in active mobility, environment, economic development, and more for the benefit of its diverse population |
78 | |||
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 |
Communauté d'agglomération Rambouillet Territoiresrt78.fr
Management of community space, economic growth, infrastructure, environment, culture, sports, generational actions, sanitation, and sustainable development across 36 communes. |
76 | |||
| 17 |
Sitrevasitreva.fr
A syndicate managing waste treatment and disposal for its members in France, operating waste collection services and recycling centers |
51 | |||
| 18 |
Options Solutionsoptions-solutions.fr
Provides reusable container supply, collection, and washing services to eliminate packaging and consumption waste in food service and retail sectors. |
43 | |||
| 19 | 32 | ||||
| 20 |
VIDEAL 78 ◽ Entreprise Adaptée - Collecte, Recyclage, Réemploi des déchets en entreprisevideal78-apr2.fr
A company specializing in sustainable recycling of electronic waste, employing disabled individuals, and developing innovative technology for plastic recycling and eco-friendly practices |
32 | |||
| 21 |
Urbasenseurbasense.fr
Urbasense provides agronomic plant monitoring services using connected sensors to ensure reliable plantations, quality control, and minimal water consumption for plant development |
26 | |||
| 22 | 26 | ||||
| 23 |
COHIN ENVIRONNEMENTcohin-environnement.com
Designs and builds wastewater treatment plants and systems for industrial and municipal needs, including renovation and compliance, offering turnkey installations and a patented biological treatment process. |
25 | |||
| 24 |
PROTERRA ENVIRONNEMENTproterra-environnement.com
The company specializes in applying geomembrane sealing devices for various types of ponds, non-hazardous waste storage cells, and implementing floating covers. |
22 | |||
| 25 |
PHILAQUAphilaqua.com
Growing company with professional team specializing in water network treatment for commercial, industrial, healthcare, residential, and municipal sectors |
21 | |||
| 26 |
CATS ECOFLUIDEecofluide.com
Design and implementation of custom oil filtration systems considering application type, oil characteristics, flow rate, maintenance cost, ROI, lifespan, and environmental protection. |
21 | |||
| 27 |
APH Environnement Servicesaphservices.fr
Specializing in sanitation services since 2005, offering maintenance, emergency response, TV inspection, compliance work, and civil engineering in the Paris region |
16 | |||
| 28 |
MANEXI DIAGNOSTICSmanexi.com
Technical consulting firm specializing in construction pollutant management, offering diagnostics, advice, and performance measurement for various building types and project stages. |
14 | |||
| 29 |
ATI-Environnementati-environnement.fr
Specializing in studying and cleaning polluted sites and soil, this company in the Paris region focuses on environmental and anticorrosion projects nationwide with a small team |
9 | |||
| 30 |
Afleyaafleya.com
Afleya specializes in managing and enhancing construction materials to promote environmental sustainability in the building sector through training, consulting, and a diagnostic app |
9 | |||
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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.
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The same list elsewhere in France
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- Environmental services companies in the Rhône department 64
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- Environmental services companies in Bourgogne-Franche-Comté 38
- Environmental services companies in the Seine-Saint-Denis department 34
- Environmental services companies in the Gironde department 32
- Environmental services companies in the Essonne department 27
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