Agglomeration communities in France

An agglomeration community (French: communauté d'agglomération, pronounced [kɔmynote daɡlɔmeʁasjɔ̃]) is a consortium of communes (municipalities) in France, created as a government structure by the Chevènement Law of 1999. It is one of four forms of intercommunality, less integrated than a métropole or a communauté urbaine but more integrated than a communauté de communes. Agglomeration communities consist of a commune of at least 15,000 inhabitants (or a prefecture with less than 15,000 inhabitants) and its independent suburbs.

As of January 2025, there are 230 agglomeration communities in France (214 in metropolitan France and 16 in the overseas departments).^[1] The population (as of 2022) of the agglomeration communities ranges from 364,744 inhabitants (CA Roissy Pays de France) to 28,318 inhabitants (CA Grand Verdun).

Several former communautés d'agglomération have been converted into communautés urbaines or métropoles, for instance those of Strasbourg, Rouen, Saint-Étienne and Caen.

List of communautés d'agglomération

The table below lists the communautés d'agglomération with more than 200,000 inhabitants (as of 2022).

Name	Seat	Number of communes	Population (2022)^[2]
CA Grand Annecy	Annecy	34	216,729
CA Grand Avignon	Avignon	16	201,600
CA Pays Basque	Bayonne	158	334,316
CA Béthune-Bruay, Artois-Lys Romane	Béthune	100	278,892
CA Cergy-Pontoise	Cergy	13	219,620
CA Cœur d'Essonne	Sainte-Geneviève-des-Bois	21	209,923
CA Lens – Liévin	Lens	36	244,474
CA Lorient Agglomération	Lorient	25	213,310
CA Mulhouse Alsace Agglomération	Mulhouse	39	276,825
CA Nîmes Métropole	Nîmes	39	265,741
CA Nord de La Réunion	Saint-Denis	3	218,801
CA Paris-Saclay	Orsay	27	323,618
CA Grand Paris Sud Seine-Essonne-Sénart	Courcouronnes	23	363,513
CA Paris - Vallée de la Marne	Torcy	12	233,856
CA Roissy Pays de France	Roissy-en-France	42	364,744
CA Saint Germain Boucles de Seine	Le Pecq	19	347,443
CA Saint-Quentin-en-Yvelines	Trappes	12	236,416
CA Territoire de la Côte Ouest	Le Port	5	221,532
CA Valence Romans Agglo	Alixan	54	229,539
CA Val Parisis	Beauchamp	15	291,093
CA Versailles Grand Parc	Versailles	18	273,663