# The 27 largest Government Administration companies in the Seine-Maritime department

Tamtam tracks 27 Government Administration companies headquartered in the Seine-Maritime department. This list ranks all of them by number of employees on LinkedIn, led by DEPARTEMENT DE LA SEINE-MARITIME, Ville du Havre and Métropole Rouen Normandie. Their median headcount is 124. The most common headquarters are Rouen (11), Le Havre (4) and Mont-Saint-Aignan (2).

These are government administration entities located in the Seine-Maritime department, primarily large public sector organizations. They encompass a range of administrative functions and public services.

Key organizations include DEPARTEMENT DE LA SEINE-MARITIME, which manages social services and infrastructure, and Ville du Havre, responsible for urban planning and cultural activities. Métropole Rouen Normandie provides essential services across 71 communes, while Carsat Normandie handles retirement and occupational health services. Ville de Rouen is a central urban administration, and Le Havre Seine Métropole focuses on economic and environmental innovation.

🇫🇷 Seine-Maritime · 27 companies · Updated Nov 13, 2026

| # | Company | Industry | Headquarters | Employees | Founded |
|---|---|---|---|---|---|
| 1 | [DEPARTEMENT DE LA SEINE-MARITIME](https://www.tamtam.ai/c/departement-de-la-seine-maritime) (seinemaritime.fr)<br>Provides essential social services, manages departmental roads, supports local communities, and promotes education, culture, economic development, and tourism in the region. | Government Administration | 🇫🇷 Rouen | 1,450 |  |
| 2 | [Ville du Havre](https://www.tamtam.ai/c/ville-du-havre) (linktr.ee)<br>local government managing urban planning, environment, port activities, culture, history, tourism, economy, education, sports, and public events | Government Administration | 🇫🇷 Le Havre | 902 |  |
| 3 | [Métropole Rouen Normandie](https://www.tamtam.ai/c/metropole-rouen-normandie) (metropole-rouen-normandie.fr)<br>Manages 71 communes, providing essential services like water, transport, waste, promoting local development, tourism, and actively addressing climate change. | Government Administration | 🇫🇷 Rouen | 886 | 2015 |
| 4 | [Ville de Rouen](https://www.tamtam.ai/c/ville-de-rouen) (rouen.fr)<br>Leading urban center in Normandy, Rouen offers a vibrant cultural scene and diverse activities Committed to quality of life, innovation and community engagement | Government Administration | 🇫🇷 Rouen | 597 |  |
| 5 | [Carsat Normandie](https://www.tamtam.ai/c/carsat-normandie) (carsat-normandie.fr)<br>Provides retirement, social action, and occupational health services. Manages substantial retirement payments, social support, and workplace prevention across the region. | Government Administration | 🇫🇷 Rouen | 552 |  |
| 6 | [Le Havre Seine Métropole](https://www.tamtam.ai/c/le-havre-seine-metropole) (lehavreseinemetropole.fr)<br>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. | Government Administration | 🇫🇷 Le Havre | 527 | 2019 |
| 7 | [Ville de Sotteville-lès-Rouen](https://www.tamtam.ai/c/ville-de-sotteville-les-rouen) (sotteville-les-rouen.fr)<br>Local government promoting environmental sustainability, community participation, economic development, and quality of life through active urban planning and social initiatives. | Government Administration | 🇫🇷 Sotteville-lès-Rouen | 206 |  |
| 8 | [Préfecture de la région Normandie et de la Seine-Maritime](https://www.tamtam.ai/c/prefecture-de-la-region-normandie-et-de-la-seine-maritime) (seine-maritime.gouv.fr)<br>Official account providing government services and information for the Normandy region and Seine-Maritime department, including social media moderation guidelines. | Government Administration | 🇫🇷 Rouen | 180 |  |
| 9 | [CCI Rouen Métropole](https://www.tamtam.ai/c/cci-rouen-metropole) (rouen-metropole.cci.fr)<br>Supporting businesses at every stage from creation to growth to transfer, representing and animating the economic life of 25,000 companies in various sectors | Government Administration | 🇫🇷 Rouen | 156 |  |
| 10 | [Ville de Grand Quevilly](https://www.tamtam.ai/c/ville-de-grand-quevilly) (grandquevilly.fr)<br>Provides local government administration, public services, community development, and support for residents and businesses in Grand Quevilly. | Government Administration | 🇫🇷 Le Grand-Quevilly | 138 |  |
| 11 | [Assurance Maladie de la Seine-Maritime](https://www.tamtam.ai/c/assurance-maladie-de-la-seine-maritime) (ameli.fr)<br>A leading social protection organization in the Rouen-Elbeuf-Dieppe area, ensuring universal access to healthcare rights, promoting health preservation, and improving healthcare efficiency | Government Administration | 🇫🇷 Rouen | 137 | 1945 |
| 12 | [Ville de Montivilliers](https://www.tamtam.ai/c/ville-de-montivilliers) (ville-montivilliers.fr)<br>This company located in Montivilliers, France, focuses on sustainable development, culture, sports, education, and community engagement in a dynamic and inclusive environment | Government Administration | 🇫🇷 Montivilliers | 133 |  |
| 13 | [CCI Normandie](https://www.tamtam.ai/c/cci-normandie) (cci.fr)<br>Represents business interests to public authorities, promotes enterprise and territorial development for over 140,000 businesses across Normandy. | Government Administration | 🇫🇷 Rouen | 126 |  |
| 14 | [Ville de Petit-Quevilly](https://www.tamtam.ai/c/ville-de-petit-quevilly) (petit-quevilly.fr)<br>Official social media channels for local government communication, community engagement, and public information sharing in Petit-Quevilly. | Government Administration | 🇫🇷 Le Petit-Quevilly | 124 |  |
| 15 | [Cour d'appel de Rouen](https://www.tamtam.ai/c/cour-d-appel-de-rouen) (cours-appel.justice.fr)<br>Company operating the court of appeal in Rouen covering Seine-Maritime and Eure, including numerous judicial, proximity, and commercial courts | Government Administration | 🇫🇷 Rouen | 120 |  |
| 16 | [Ville de Lillebonne](https://www.tamtam.ai/c/ville-de-lillebonne) (lillebonne.fr)<br>A city located between Le Havre and Rouen, Lillebonne is known for its industrial presence and rich archaeological and historical heritage | Government Administration | 🇫🇷 Lillebonne | 77 | 1900 |
| 17 | [CODAH (Communauté de l'agglomération havraise)](https://www.tamtam.ai/c/codah-communaute-de-l-agglomeration-havraise)<br>An intercommunal public entity formed in 2001, uniting 275,000 residents across 3 communities for a cohesive urban development project | Government Administration | 🇫🇷 Le Havre | 73 | 2001 |
| 18 | [Ville de Petit-Caux](https://www.tamtam.ai/c/ville-de-petit-caux) (petitcaux.fr)<br>Government administration company based in Normandie, France, focused on serving the community of Petit-Caux Located at 3 Rue du Val des Comtes | Government Administration | 🇫🇷 Petit-Caux | 65 | 2016 |
| 19 | [CDG 76 (Centre de Gestion de la fonction publique territoriale de Seine-Maritime)](https://www.tamtam.ai/c/cdg-76-centre-de-gestion-de-la-fonction-publique-territoriale-de-seine-maritime) (cdg76.fr)<br>Support local governments and public institutions with human resources management, statutory assistance, health, prevention, and employment services in Normandy. | Government Administration | 🇫🇷 Isneauville | 62 | 1984 |
| 20 | [Urssaf Haute-Normandie](https://www.tamtam.ai/c/urssaf-haute-normandie) (urssaf.fr)<br>The company is a network that collects social security contributions, promotes employment policies, prevents payment difficulties, fights against illegal labor, and simplifies social formalities | Government Administration | 🇫🇷 Rouen | 56 |  |
| 21 | [Direction Régionale du Service Médical de Normandie](https://www.tamtam.ai/c/direction-regionale-du-service-medical-de-normandie) (ameli.fr)<br>The company ensures proper healthcare resource allocation, coordinates patient care, promotes prevention, and combats fraud, serving over 60 million insured individuals | Government Administration | 🇫🇷 Rouen | 53 | 1945 |
| 22 | [Ville de Mont-Saint-Aignan](https://www.tamtam.ai/c/ville-de-mont-saint-aignan) (montsaintaignan.fr)<br>A town of 20,000 residents in Rouen, France, Mont-Saint-Aignan offers quality living, universities, businesses, and public services with diverse employment opportunities | Government Administration | 🇫🇷 Mont-Saint-Aignan | 48 | 1819 |
| 23 | [Agglo Fécamp Caux Littoral](https://www.tamtam.ai/c/agglo-fecamp-caux-littoral) (agglo-fecampcauxlittoral.fr)<br>The company serves a population of 40,000 across 33 municipalities in the Fecamp Caux Littoral region, providing various services and support | Government Administration | 🇫🇷 Fécamp | 44 |  |
| 24 | [Communauté de communes Falaises du Talou](https://www.tamtam.ai/c/communaute-de-communes-falaises-du-talou) (falaisesdutalou.fr)<br>This company is a community of 24 municipalities in Normandy, Seine-Maritime, with a population of around 24,000 inhabitants | Government Administration | 🇫🇷 Envermeu | 33 | 2017 |
| 25 | [Assurance Maladie du Havre](https://www.tamtam.ai/c/assurance-maladie-du-havre) (ameli.fr)<br>Working at this company means being part of a team focused on results, using skills to protect the health of over 60 million insured individuals | Government Administration | 🇫🇷 Le Havre | 21 | 1945 |
| 26 | [COMMUNE DE MONT SAINT AIGNAN](https://www.tamtam.ai/c/commune-de-mont-saint-aignan) (montsaintaignan.fr)<br>Organization and promotion of local cultural, social, and recreational events, urban development projects, and community services for residents. | Government Administration | 🇫🇷 Mont-Saint-Aignan | 19 |  |
| 27 | [Ville du Trait](https://www.tamtam.ai/c/ville-du-trait) (letrait.fr)<br>A small town in Normandy, providing a variety of services and amenities to its residents and neighboring communities, while focusing on cultural, social, digital, and ecological transitions | Government Administration | 🇫🇷 Le Trait | 10 |  |

## 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 13, 2026.

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- [Multinational companies in the Seine-Maritime department](https://www.tamtam.ai/l/multinational-companies-seine-maritime) (89)
- [Manufacturers in the Seine-Maritime department](https://www.tamtam.ai/l/manufacturers-seine-maritime) (72)
- [Companies with in-house R&D in the Seine-Maritime department](https://www.tamtam.ai/l/r-and-d-companies-seine-maritime) (67)
- [Public sector organisations in the Seine-Maritime department](https://www.tamtam.ai/l/public-sector-organisations-seine-maritime) (65)
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- [Critical infrastructure operators in the Seine-Maritime department](https://www.tamtam.ai/l/critical-infrastructure-operators-seine-maritime) (46)
- [Family-owned companies in the Seine-Maritime department](https://www.tamtam.ai/l/family-owned-companies-seine-maritime) (44)
- [IT services companies in the Seine-Maritime department](https://www.tamtam.ai/l/it-services-companies-seine-maritime) (40)
- [Hardware manufacturers in the Seine-Maritime department](https://www.tamtam.ai/l/hardware-companies-seine-maritime) (38)
- [Education providers in the Seine-Maritime department](https://www.tamtam.ai/l/education-companies-seine-maritime) (36)
- [Healthcare providers in the Seine-Maritime department](https://www.tamtam.ai/l/healthcare-providers-seine-maritime) (34)
- [Logistics companies in the Seine-Maritime department](https://www.tamtam.ai/l/logistics-companies-seine-maritime) (34)
- [Financial services firms in the Seine-Maritime department](https://www.tamtam.ai/l/financial-services-firms-seine-maritime) (32)
- [IT Services and IT Consulting companies in the Seine-Maritime department](https://www.tamtam.ai/l/it-services-and-it-consulting-companies-seine-maritime) (30)
- [Real Estate companies in the Seine-Maritime department](https://www.tamtam.ai/l/real-estate-companies-seine-maritime) (30)
- [Higher Education companies in the Seine-Maritime department](https://www.tamtam.ai/l/higher-education-companies-seine-maritime) (28)
- [Software Development companies in the Seine-Maritime department](https://www.tamtam.ai/l/software-development-companies-seine-maritime) (28)
- [Industrial Machinery Manufacturing companies in the Seine-Maritime department](https://www.tamtam.ai/l/industrial-machinery-manufacturing-companies-seine-maritime) (27)
- [Consulting firms in the Seine-Maritime department](https://www.tamtam.ai/l/consulting-firms-seine-maritime) (26)
- [Hospitals and Health Care companies in the Seine-Maritime department](https://www.tamtam.ai/l/hospitals-and-health-care-companies-seine-maritime) (25)

## The same list elsewhere in France

- [Government Administration companies in France](https://www.tamtam.ai/l/government-administration-companies-france) (1,862)
- [Government Administration companies in Île-de-France](https://www.tamtam.ai/l/government-administration-companies-ile-de-france) (496)
- [Government Administration companies in Auvergne-Rhône-Alpes](https://www.tamtam.ai/l/government-administration-companies-auvergne-rhone-alpes) (201)
- [Government Administration companies in Grand Est](https://www.tamtam.ai/l/government-administration-companies-grand-est) (168)
- [Government Administration companies in Provence-Alpes-Côte d'Azur](https://www.tamtam.ai/l/government-administration-companies-provence-alpes-cote-dazur) (150)
- [Government Administration companies in Nouvelle-Aquitaine](https://www.tamtam.ai/l/government-administration-companies-nouvelle-aquitaine) (145)
- [Government Administration companies in Occitanie](https://www.tamtam.ai/l/government-administration-companies-occitanie) (138)
- [Government Administration companies in Hauts-de-France](https://www.tamtam.ai/l/government-administration-companies-hauts-de-france) (126)
- [Government Administration companies in Pays de la Loire](https://www.tamtam.ai/l/government-administration-companies-pays-de-la-loire) (96)
- [Government Administration companies in Normandy](https://www.tamtam.ai/l/government-administration-companies-normandy) (93)
- [Government Administration companies in Brittany](https://www.tamtam.ai/l/government-administration-companies-brittany) (81)
- [Government Administration companies in Bourgogne-Franche-Comté](https://www.tamtam.ai/l/government-administration-companies-bourgogne-franche-comte) (69)
- [Government Administration companies in Centre-Val de Loire](https://www.tamtam.ai/l/government-administration-companies-centre-val-de-loire) (64)
- [Government Administration companies in the Nord department](https://www.tamtam.ai/l/government-administration-companies-nord) (58)
- [Government Administration companies in the Bouches-du-Rhône department](https://www.tamtam.ai/l/government-administration-companies-bouches-du-rhone) (57)
- [Government Administration companies in the Seine-Saint-Denis department](https://www.tamtam.ai/l/government-administration-companies-seine-saint-denis) (53)
- [Government Administration companies in the Rhône department](https://www.tamtam.ai/l/government-administration-companies-rhone) (51)
- [Government Administration companies in the Yvelines department](https://www.tamtam.ai/l/government-administration-companies-yvelines) (51)
- [Government Administration companies in the Gironde department](https://www.tamtam.ai/l/government-administration-companies-gironde) (46)
- [Government Administration companies in the Val-de-Marne department](https://www.tamtam.ai/l/government-administration-companies-val-de-marne) (45)
- [Government Administration companies in the Hauts-de-Seine department](https://www.tamtam.ai/l/government-administration-companies-hauts-de-seine) (43)
- [Government Administration companies in the Haute-Garonne department](https://www.tamtam.ai/l/government-administration-companies-haute-garonne) (42)
- [Government Administration companies in the Seine-et-Marne department](https://www.tamtam.ai/l/government-administration-companies-seine-et-marne) (39)
- [Government Administration companies in Paris](https://www.tamtam.ai/l/government-administration-companies-paris) (176)

## The same list elsewhere

- [Government Administration companies in the world](https://www.tamtam.ai/l/government-administration-companies-in-the-world) (8,776)
- [Government Administration companies in Europe](https://www.tamtam.ai/l/government-administration-companies-in-europe) (4,201)

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Source: https://www.tamtam.ai/l/government-administration-companies-seine-maritime