Mécénat Musical Société Générale is the main sponsor of Les Siècles.
The orchestra is also financed by the French Ministère de la Culture et de la Communication and DRAC Hauts-de-France. Since 2011, the orchestra is supported by the Conseil Départemental de l’Aisne to reinforce its artistic and educational presence on this territory. The orchestra is in residency in the Cité de la Musique et de la Danse of Soissons with the support of the Conseil Départemental de l’Aisne and région Hauts-de-France. The orchestra regularly performs in Hauts-de-Seine with the support of the city of Nanterre. Les Siècles is resident orchestra in Théâtre-Sénart of Lieusaint, and associated artist in Théâtre de Nîmes, in Les Musicales festival in Normandy and Berlioz Festival of La Côte-Saint-André. Les Siècles have a strong partnership with the Philharmonie of Paris and Opéra-Comique theater.
The orchestra is sponsored by the Palazzetto Bru Zane-Centre de musique romantique française, the Echanges and Bibliothèques association and occasionally by the SPEDIDAM, ADAMI, Bureau Export, Institut Français, SPPF and FCM.
Les Siècles is administrator member of the FEVIS and the Association Française des Orchestres, then associated member of SPPF.