Personal life
In 2003, Gayet married Argentine author and screenwriter Santiago Amigorena, but they divorced in 2006. The couple have two children.
Gayet is a centre-left activist, having appeared in a video supporting François Hollande during the 2012 French presidential election. She is a member of the Support Committee of the PS candidate for the 2014 Paris mayoral election, Anne Hidalgo. She also supported same-sex marriage in France.
In 2013 rumours started circulating that Gayet was in a secret relationship with Hollande. On 10 January 2014, a story in the tabloid Closer featured seven pages of alleged revelations and photos about the affair, provoking wider media coverage. Hollande said he "regretted this violation of his private life" and was "thinking about" pursuing a legal response, but did not deny the substance of the story. The 10 January issue was so popular that Closer "reprinted the issue, with a further 150,000 copies scheduled to hit newsstands" on 15 January 2014. On 16 January 2014, the AFP news agency reported that Gayet would sue Closer for €50,000 in damages and €4,000 in legal costs.
On 27 March 2014, a French court ordered Closer magazine to pay Gayet €15,000 ($20,700) for publishing the photos that revealed an affair between her and President Hollande. In November 2014, she was photographed with Hollande at the Élysée Palace gardens; it was revealed that her affair with Hollande was ongoing and that she was spending at least four nights a week with him there.
Gayet married Hollande on 4 June 2022 in Tulle.
In October 2022, she was appointed to the supervisory board of French professional rugby union club CA Brive.
Gayet is of French as well as distant Polish, German, Maltese, and Corsican Italian descent.