The companies listed operate critical infrastructure in Seine-Maritime, with a notable concentration in the public and semi-public sectors. These are mostly large organizations, with many employing over 500 people. Matmut, an insurance provider, employs 4244 people, while CHU de Rouen, a hospital network, has 3823 employees. Banking services are represented by Crédit Agricole Normandie-Seine and Caisse d'Epargne Normandie, with 1566 and 1402 employees respectively. HAROPA PORT manages a major French river-maritime port network.
A significant pattern is the prevalence of public services and regulated industries. Hospitals and healthcare facilities are prominent, including Groupe Hospitalier du Havre - GHH, a leading healthcare provider, and Clinique Saint Hilaire, a medical surgical facility. Government administration entities like Métropole Rouen Normandie and Le Havre Seine Métropole are also key, managing communes and promoting local development.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 | 4,244 | ||||
| 2 |
CHU de Rouenchu-rouen.fr
Large hospital network providing patient care, medical education, and research, supporting regional healthcare and training future health professionals. |
3,823 | |||
| 3 |
Crédit Agricole Normandie-Seineca-normandie-seine.fr
Regional bank with 130 branches and online services for individuals, professionals, farmers, businesses, and public communities in Eure and Seine-Maritime. |
1,566 | |||
| 4 |
Caisse d'Epargne Normandiecaisse-epargne.fr
Regional bank serving individuals, professionals, businesses, and local authorities with tailored financial advice and community project support in Normandy. |
1,402 | |||
| 5 |
Groupe Hospitalier du Havre - GHHch-havre.fr
Leading healthcare provider, comprehensive care, advanced medical technology, collaboration with other hospitals, diverse medical professions, round-the-clock technical platform. |
893 | |||
| 6 |
HAROPA PORTharopaport.com
Manages a major French river-maritime port network, connecting international shipping with a vast hinterland, handling significant maritime and river traffic. |
892 | |||
| 7 |
Métropole Rouen Normandiemetropole-rouen-normandie.fr
Manages 71 communes, providing essential services like water, transport, waste, promoting local development, tourism, and actively addressing climate change. |
886 | |||
| 8 |
SDIS 76 - Sapeurs-pompiers de la Seine-Maritimesdis76.fr
Departmental organization managing emergency services, including fire fighting, victim rescue, risk prevention, and specialized interventions in hazardous environments. |
657 | |||
| 9 |
Carsat Normandiecarsat-normandie.fr
Provides retirement, social action, and occupational health services. Manages substantial retirement payments, social support, and workplace prevention across the region. |
552 | |||
| 10 |
Le Havre Seine Métropolelehavreseinemetropole.fr
This Metropolis aims for excellence through innovation in economy, society, and environment. It focuses on green and blue economy, higher education, and tourism, serving its 275,000 inhabitants. |
527 | |||
| 11 |
Groupe SOGESTRANsogestran.com
Inland waterway and maritime shipowner offering environmentally friendly transport for oil, chemicals, dry bulk, general goods, with focus on quality and safety |
303 | |||
| 12 |
Centre hospitalier intercommunal Elbeuf Louviers Val de Reuilchi-elbeuf-louviers.fr
Public healthcare facility in Normandy with 1083 beds, 2143 staff including 267 medical personnel, two hospital sites, maternity, and five nursing homes. |
291 | |||
| 13 |
LVO Grouplv-overseas.fr
Global logistics provider with presence in France, French overseas territories, Asia, Africa, Middle East, and US, offering flexible transport solutions worldwide |
281 | |||
| 14 |
Transdev Rouen (TCAR)transdev.com
Providing safe, efficient, and innovative mobility solutions for residents of the Rouen Normandy Metropolis to navigate the area |
274 | |||
| 15 |
Clinique Saint Hilaireclinique-sainthilaire.fr
Medical surgical facility with 223 beds, 380 staff, 75 practitioners, offering innovative care across surgical, cardiovascular, and oncology specialties. |
265 | |||
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 |
Transdev Normandietransdev.com
Providing sustainable, innovative, and secure mobility solutions for communities, Transdev Normandie collaborates with local authorities and businesses to optimize transportation services |
243 | |||
| 17 |
UGECAM NORMANDIEgroupe-ugecam.fr
A non-profit group in France providing healthcare and support services for people with physical and intellectual disabilities, with a focus on equality and quality care |
224 | |||
| 18 |
VYV 3 Normandienormandie.vyv3.fr
Provides extensive medical and paramedical care, social support services, and community health programs across Normandy for diverse populations. |
222 | |||
| 19 |
Caux Seine agglocauxseine.fr
Caux Seine agglo is an intermunicipal cooperation organization uniting 50 municipalities and 77,777 residents, promoting economic and social development in the region |
212 | |||
| 20 |
HOPITAL PRIVE DE L'ESTUAIREhopital-prive-de-l-estuaire-le-havre.ramsaysante.fr
A healthcare facility in Le Havre, part of Ramsay Santé group, providing comprehensive inpatient and outpatient services with a focus on high-quality patient care |
212 | |||
| 21 |
CLINIQUE DU CEDREclinique-du-cedre.fr
A hospital and health care company located in Bois Guillaume, France, specializing in providing medical services to patients |
184 | |||
| 22 |
Assurance Maladie de la Seine-Maritimeameli.fr
A leading social protection organization in the Rouen-Elbeuf-Dieppe area, ensuring universal access to healthcare rights, promoting health preservation, and improving healthcare efficiency |
137 | |||
| 23 |
CLINIQUE DES ORMEAUXormeaux.com
Hospital & health care company located in Le Havre, France, providing medical services to patients in need of healthcare |
127 | |||
| 24 |
Générale de Manutention Portuairegmportuaire.fr
Leading French port handling company managing container terminals, exceptional cargo, refrigerated container repair, and inland transport with eco-friendly, digitalized operations. |
127 | |||
| 25 |
Les Escales - EHPAD publics du Havreehpad-lesescales.fr
Les Escales provides specialized care for elderly residents in Le Havre through 6 public nursing homes, alongside home care services |
115 | |||
| 26 |
CLINIQUE OCEANEclinique-oceane.ramsaysante.fr
Located in Le Havre, Clinique Océane, part of Ramsay Santé group, provides exceptional healthcare services in a welcoming environment since 2012 |
105 | |||
| 27 |
Compagnie Fluviale de Transportsogestran.com
A company that specializes in French barging services and operates as a shipping operator as well |
96 | |||
| 28 |
Vidi - nora imagerienora-imagerie.fr
A group of medical imaging centers in Calvados, Eure, and Seine-Maritime, offering various medical imaging and interventional procedures, focusing on patient care |
75 | |||
| 29 | 71 | ||||
| 30 |
Centre Hospitalier Durécu-Lavoisier (CHDL)chdl.fr
The company provides medical care and rehabilitation services through nursing homes within the Durécu-Lavoisier Hospital Center and L'Eau Vive |
69 | |||
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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
- Critical infrastructure operators in France 2,721
- Critical infrastructure operators in Île-de-France 780
- Critical infrastructure operators in Auvergne-Rhône-Alpes 299
- Critical infrastructure operators in Grand Est 257
- Critical infrastructure operators in Occitanie 216
- Critical infrastructure operators in Nouvelle-Aquitaine 209
- Critical infrastructure operators in Provence-Alpes-Côte d'Azur 200
- Critical infrastructure operators in Hauts-de-France 174
- Critical infrastructure operators in the Hauts-de-Seine department 169
- Critical infrastructure operators in Pays de la Loire 127
- Critical infrastructure operators in Brittany 120
- Critical infrastructure operators in Normandy 103
- Critical infrastructure operators in the Bouches-du-Rhône department 98
- Critical infrastructure operators in the Rhône department 94
- Critical infrastructure operators in Centre-Val de Loire 87
- Critical infrastructure operators in the Nord department 87
- Critical infrastructure operators in Bourgogne-Franche-Comté 76
- Critical infrastructure operators in the Haute-Garonne department 64
- Critical infrastructure operators in the Gironde department 63
- Critical infrastructure operators in the Loire-Atlantique department 59
- Critical infrastructure operators in the Hérault department 57
- Critical infrastructure operators in the Seine-Saint-Denis department 53
- Critical infrastructure operators in the Ille-et-Vilaine department 45
- Critical infrastructure operators in Paris 331