Lily Collias is an American actress best known for her breakthrough role as Sam in Good One (2024), a coming-of-age drama directed by India Donaldson. The film premiered in the U.S. Dramatic Competition at the 2024 Sundance Film Festival, and later screened in the Directors' Fortnight section at the 2024 Cannes Film Festival.

Collias grew up in Santa Monica, Los Angeles, and moved to New York to pursue acting. She studied at The New School and trained at the Lee Strasberg Theatre & Film Institute. Before Good One, she appeared in Palm Trees and Power Lines (2022). Her upcoming credits include Roofman (2025) and The Young People (2026).