McDowell was born in Los Angeles, California, the son of English actor Malcolm McDowell and American Actress Mary Steenburgen. He has an older sister, Lilly Amanda (born 1981), and three younger half-brothers, Beckett Taylor (born 2004), Finnian Anderson (born 2006), and Seamus Hudson (born 2009), from his father's marriage to Kelley Kuhr.
In 2006, he received his MFA in Directing from the AFI Conservatory in Los Angeles.
In 2011, McDowell's Twitter feed, @charliemcdowell, was described by Time as "one of the most hilarious Twitter feeds out there," and in 2013 Three Rivers Press published McDowell's book, Dear Girls Above Me, based on his Twitter feed.
His debut film, The One I Love, starring Mark Duplass and Elisabeth Moss had its world premiere at the Sundance Film Festival in January 2014, where shortly after it was acquired by RADiUS-TWC and released in August 2014. In 2015, McDowell directed Sarah Silverman's HBO pilot. McDowell's next film The Discovery, stars Rooney Mara, Jason Segel, and Robert Redford. The film premiered at the Sundance Film Festival and was acquired by Netflix for a global release in 2017.
In March 2017, film-maker McDowell announced he was adapting author Don DeLillo's novel Zero K as a limited series for FX with Noah Hawley and Scott Rudin producing.
