The 27-year-old received her first-ever nod from the Academy for her portrayal of Tonya Harding in the film, which she also produced.
Following the movie, which Margot attended alongside her parents, brothers, and friends, the star celebrated in the best way possible: with plenty of drinks and dancing.
Her brother Cameron took to Instagram to praise his talented big sister, writing: "There’s nothing I could say that articulates how proud I am of this one #whatamoment #academyawardnomaninee! [sic]"
Take a look at the full list of Oscar nominations here.