William Bouygues began his career in 2011 with Bouygues Construction in the Bouygues Bâtiment Île-de-France - Rénovation Privée teams, where he held the post of works supervisor before joining the sales teams. 

Drawing on his experience, in 2016 he joined Bouygues Bâtiment International in the structure and development teams.

After an assignment in Bouygues Energy & Services, in January 2019 he became property development manager at Linkcity (Bouygues Construction's property development subsidiary) before taking over as Executive Vice President, Strategic Projects in Bouygues Immobilier's (Real Estate) commercial property division in 2021. 

Since 2024, he has been Deputy Chief Executive Officer for Property Development Subsidiaries in France and internationally at Bouygues Immobillier.

In June 2025, William Bouygues has been appointed Group Vice President - Industries for the Colas Group. Reporting to the CEO, Pierre Vanstoflegatte, he will be a member of the Colas Strategic Committee.