Chibundu Onuzo was born in Nigeria in 1991, the youngest of four children of parents who are doctors, and grew up there in Lagos. She moved to England when she was 14 to study at an all girls' school in Winchester, Hampshire, for her GCSEs, and at the age of 17 began writing her first novel, which was signed two years later by Faber and Faber and was published when she was 21.She was the youngest female writer ever taken on by the publisher.[7] Reviewing her second book, Welcome to Lagos (2016), Helon Habila wrote in The Guardian: "Onuzo’s portrayal of human character is often too optimistic, her view of politics and society too charitable; but her ability to bring her characters to life, including the city of Lagos, perhaps the best-painted character of all, is impressive."

Onuzo received a first-class bachelor's degree in history from King's College London (2012),and went on to earn a master's degree in public policy from University College London. As of 2017, she is studying for a PhD at King's College London.