She gained mainstream attention in the Netflix series Everything Sucks! (2018) for her role as Emaline and has portrayed Eden in the Hulu series The Handmaid's Tale (2018) and Alice in the HBO miniseries Sharp Objects (2018).
She has starred as Cassie Howard in the HBO teen drama series Euphoria since 2019 and as Olivia Mossbacher in The White Lotus since 2021.
In film, she had a role in Quentin Tarantino's 2019 comedy-drama Once Upon a Time in Hollywood, portraying Dianne "Snake" Lake, a member of the Manson Family.
Sydney Bernice Sweeney was born on September 12, 1997, in Spokane, Washington, the first of two children of a lawyer mother and a father who works in the medical field.
Sweeney is a trained MMA fighter, and competed in grappling in high school.
Sweeney has been engaged to her longtime boyfriend, Chicago-based restaurateur Jonathan Davino, since February 2022.