Theodora Ellen Bonwick (27 December 1876 – 10 November 1928) was a British headteacher, trade unionist, educationist and suffragette.

Bonwick trained as a teacher at Stockwell College of Education, where she obtained a BA degree.

Bonwick wrote a long letter to Christabel and another to Sylvia asking her to "lie low" as the public should not see more internal conflict in the WSPU.

[4] Sylvia was ejected from the WSPU for her socialist and democratic views[5] and Borwick became the president of the Women Teachers' Franchise Union (WTFU) in 1914.

In 1990 Bonwick was chosen with three others, Agnes Dawson, Emily Phipps and Ethel Froud, to be featured in Hilda Kean's book, 'Deeds Not Words: The Lives of Suffragette Teachers'.