Geldof was born in London in 1989, the second daughter of Bob Geldof and Paula Yates. She is the granddaughter of Hughie Green. Her sisters are Fifi Trixibelle Geldof and Pixie Geldof. She also has a younger half-sister, Tiger Lily Hutchence Geldof.
She grew up in Chelsea, London and Faversham, Kent, and was educated at Queen's College, London. After moving out of her father's house at eighteen, Peaches rented a flat in Islington, North London, but gave up her lease to move to New York with then-husband, Max Drummey.