Following the 1999 Ivorian coup d'état, he resumed a private sector career and rejoined McKinsey in Paris from 2000 to 2002, then worked as a senior executive for Aviva before being recruited by Prudential.

In 2020, Thiam was appointed by the shareholders of the Kering Foundation to become part of the board of directors, as well as to take the position as Chair of the Audit Committee.

Thiam's mother, Marietou, was the niece of Chief Félix Houphouët-Boigny, the founder and first President of Côte d'Ivoire.

[11] Tidjane's uncle, Habib Thiam, was Prime Minister of Senegal for more than 10 years and also served as President of the National Assembly.

In April 1994, at the request of the new president, Thiam left France and McKinsey to go back to Abidjan and become the CEO of the National Bureau for Technical Studies and Development (BNETD),[15] an infrastructure development and economic advisory body with more than 4,000 staff, reporting directly to the President and the Prime Minister.

In August 1998, in addition to his role at the BNETD, where he became chairman, Thiam formally joined the cabinet and was appointed Minister of Planning and Development.

He implemented flagship projects including the Azito power plant (nominated by the Financial Times as one of the boldest successful investment decisions in the world[16]), the renovation of Abidjan airport and the construction of the Riviera Marcory toll bridge, whose financing was closed a few days before the 1999 coup.

General Guéï, the new head of state, offered him the position of chief of staff, but he declined and left the country in early 2000.

[10] On returning to Europe, Thiam was offered a partnership by McKinsey in Paris, becoming one of the leaders of the company's financial institutions practice.

In January 2007, after Richard Harvey announced he would step down[18] as chief executive of Aviva, Thiam was tipped as a possible future head of the group.

In March 2009, Thiam was named chief executive, effective from October, after Mark Tucker chose to step down.

[22] AIA was later floated on the Hong Kong Stock Exchange, and the value of the company quickly rose above Prudential's original bid price.

[31] Thiam was appointed the chief executive officer (CEO) of Swiss investment bank and financial services company Credit Suisse Group AG on 10 March 2015.

[48] Established by the Seoul G20 summit in 2010, the panel was a grouping of figures from leading financial institutions and development agencies given the task of producing concrete proposals to encourage private sector investment in infrastructure projects in emerging economies.

The report set out proposals for building a new economic partnership based on a business relationship between France and the African continent, particularly the countries of Sub-Saharan Africa.

[52] In early 2021, he was appointed by the G20 to the High Level Independent Panel (HLIP) on financing the global commons for pandemic preparedness and response, co-chaired by Ngozi Okonjo-Iweala, Tharman Shanmugaratnam and Lawrence Summers.

[58] In July 2011, Thiam was awarded the rank of Chevalier of the Légion d'honneur by the French government in recognition of his significant contribution to civil life for more than 20 years.

[59] In 2013, he was awarded the Grand Prix de l’Économie, organised by Les Échos and Radio Classique, in partnership with law firm Freshfields Bruckhaus Deringer.

[60] In July 2018, business and finance magazine Euromoney named Thiam "Banker of the Year 2018", citing his "radical three-year plan" that had "reinvented" Credit Suisse.

[1] On February 7, 2025, Tidjane Thiam announced that he had renounced his French nationality in order to be eligible for the presidential election on October 25, 2025.