Margotton studied journalism at Bietry school, which was named after French journalist Charles Bietry [fr].[1] In 1992, he started working for Canal+ as an intern.[1] Margotten and Darren Tulett were the French language commentators on the Pro Evolution Soccer 2013 game.[2] In 2014, Margotten started presenting La Data Room de Canal + (The Canal+ data room), a weekly short programme that looks into the statistics of football matches.[3] In the same year, Margotten suggested that matches between Paris Saint-Germain and Marseille should become a derby match.[4]
In 2016, Margotton moved from Canal+ to TF1, as he wanted to spend his weekends with his family rather than at football matches.[1][lower-alpha 1] His first match for TF1 was the Téléfoot coverage of an international friendly between France and Cameroon.[1] He was chosen ahead of Christian Jeanpierre to present Téléfoot's coverage of France matches at UEFA Euro 2016, and commentated alongside Bixente Lizarazu.[7][8] In September 2017, Margotton began hosting Rendez-vous Sport, a two-minute summary programme about football results and players.[9] Prior to the 2018 FIFA World Cup, Margotten and Nicolas Glimois [fr] hosted a documentary 98, secrets d'une victoire (98, secrets of a victory) about France's victory at the 1998 FIFA World Cup.[10] After the 2018 World Cup, Margotten replaced Jeanpierre as the main presenter of Téléfoot.[11][12] Margotten and Lizarazu commentated for the Téléfoot coverage of the 2019 FIFA Women's World Cup.[13]
Aside from football, Margotton has commentated for TF1 on handball. He commentated on the 2017 Men's[14] and Women's World Handball Championships,[15] the 2018 Women's EHF Champions League,[16] and the 2019 World Men's Handball Championship.[17]
In 2019, Margotton appeared on a special edition of Qui veut gagner des millions ? to raise money for Notre-Dame de Paris
following the fire there. Margotten and Alessandra Sublet won 24,000€.[18]