In 1988, on a Zurich to London FLIGHT, she met Robert Louis-Dreyfus. They married in 1992 and had three sons. Margarita, who had been working for a circuit-board equipment seller, became a full-time wife and mother. She took over as chairman of the Louis Dreyfus Group in 2009, following her husband's death from leukemia.
In 2016, she had a net worth of $9.5 billion. She is a Swiss citizen living in Zurich with her three sons (Éric born in 1992, and twins, Maurice and Kyril, born in 1998), according to Forbes. Her partner is Philipp Hildebrand, the former head of the Swiss central bank. She gave birth to twin girls on 21 March 2016.