St Hilda's was founded in 1893 as an Oxford hall for women by Dorothea Beale, Principal of the Cheltenham Ladies' College. Miss Beale is said to have chosen St Hilda of Whitby (614-680) because she was head of the most important house of education of her time. Whitby Abbey, a double monastery of women and men in adjoining quarters, was famous for its learning and for training at least five bishops.
In 1896 St Hilda's was accepted as a recognized hall for women by the Association for Promoting the Higher Education of Women (A.E.W.), and in 1897 the Hall became an incorporated company with its own governing council. In 1901 St Hilda's Oxford was amalgamated with another Beale project, St Hilda's Cheltenham, to form St Hilda's Incorporated College.
In 1910 the University formally acknowledged the existence of female students in Oxford by forming the Delegacy for Women Students, and St Hilda's became a recognized society for women students. In 1920 women were finally permitted to become members of the University; for the first time women students were undergraduates and eligible for Oxford degrees.
In 1926 St Hilda's Incorporated College was disbanded and St. Hilda's Oxford was incorporated by Royal Charter as St Hilda's College, Oxford. Cheltenham Ladies' College had representatives on the St Hilda's Council, but in 1955 this final link was broken when a new charter and statutes gave St Hilda's self-government.
In 1959 the women's societies made an application to the University to be admitted as full Colleges of the University. This was agreed, and the change in status was effected by a supplemental charter and amended statutes in 1961.
The Centenary was celebrated in 1993, and St. Hilda's was the only women's college in the University between 1994 and 2008. On 7th June 2006 the Governing Body voted to change the Statutes and Charter in order to be able to admit men to the College. A supplemental charter was granted in October 2007, and men were admitted for the first time in 2008.
St Hilda's College celebrated its 125th anniversary in 2018.