Hannah Tatum Whitall Smith (February 7, 1832 - May 1, 1911) was a lay speaker and author in the Holiness movement in the United States and the Higher Life movement in the United Kingdom of Great Britain and Ireland. She was also active in the Women's suffrage movement and the Temperance movement.

Born in Philadelphia, Smith was from a long line of prominent and influential Quakers in New Jersey. Hannah Tatum Whitall was the daughter of John Mickle Whitall and Mary Tatum Whitall. Her most famous ancestor was Ann Cooper Whitall.

Hannah Whitall Smith's book The Christian's Secret of a Happy Life (1875) is an extremely popular book of Christian mysticism and practical Holiness theology. It is still widely read today. She wrote her spiritual autobiography, The Unselfishness of God And How I Discovered It, in 1903. Many publications of that book omit the three chapters which explain how she became a Christian universalist. (wikipedia.org)