Nicolas Théry graduated from the ENA in 1989. He spent the first part of his working life in the civil service in the Inspectorate of Finances and the Treasury. Subsequently, he was an advisor to Dominique Strauss-Kahn, the Minister of the Economy and Finance, and then chief of staff to the Budget Secretary, Florence Parly.

As a fervent proponent of good industrial relations, he then took up a role with the CFDT (Confédération française démocratique du travail), France’s largest national labor organization, working under its leader Nicole Notat as Confederation Secretary for Economic Affairs.

He joined the European Commission in 2002 as Chief of Staff to Pascal Lamy, Commissioner for International Trade. He then worked in the Directorate-General for Enterprise before serving at the EU Directorate-General for the Environment as Director of negotiations with the Member States and the European Parliament.

Nicolas Théry joined Crédit Mutuel group's insurance arm, Assurances du Crédit Mutuel, in 2009. He performed numerous roles within the mutual banking group before serving as Chairman and Chief Executive Officer of CIC Est from 2012 to 2016.

In 2014, Nicolas Théry was elected Chairman of Crédit Mutuel Alliance Fédérale and CIC. In 2016, he was also appointed Chairman of the Centre Est Europe federation and Confédération Nationale du Crédit Mutuel. A member of the Executive Committee of the French Banking Federation (FBF) since 2016, he served as its Chairman from September 2021 to August 2022, a first for the Crédit Mutuel group.

Nicolas Théry has been an advisor to the Chairman of Crédit Mutuel since April 2024. He also chairs the Crédit Mutuel Alliance Fédérale and Crédit Mutuel foundations for the promotion of reading.