Hypatia Bradlaugh Bonner was born in Hackney, London, a daughter of Charles Bradlaugh, the first openly atheist Member of the British Parliament, and his wife Susannah Lamb Hooper. She was educated at private schools in London and Paris, and qualified as a science teacher at the University of London in 1878. She taught at the Hall of Science run by the National Secular Society (founded by her father) and the Rationalist Press Association. In 1882, she married Arthur Bonner and the couple merged their surnames. She wrote a biography of her father, Charles Bradlaugh: His Life and Work, published in 1895, served as editor of a journal, The Reformer, and wrote for many secularist periodicals. She was an ardent peace advocate and feminist, proponent of penal reform, and opponent of blasphemy laws and the death penalty who published several books on these topics. She was appointed a Justice of the Peace for London in 1922.