Dorothy Thomas was born in Toronto, Ontario, Canada, on May 24, 1895.

She was educated in Toronto and practiced law there as a junior solicitor before she moved to Jacksonville in 1919, for reasons of health. She was married to Wayne Thomas in Jacksonville in July, 1921; moved to Tampa in 1922. She helped establish the first lunchroom for Henry Mitchell School in 1922 and was thereafter active in educational, civic and public health work. She served various times as president of the Tampa Civic Association, Hillsborough County Federation of Women's Clubs, and was for several years a member of the Hillsborough County Welfare Board and the Juvenile Board of Visitors, which controls and operates the Juvenile Home. She was also a member of Story Women's League, Community Chest, Girl Scouts, Friday Morning Musical, Cancer and T.B. Control.

On Sunday, April 24, 1949 the Civitan Club and Hillsborough County paid tribute to Mrs. Thomas, dedicating the Dorothy Thomas Building at the, then known, Hillsborough County Juvenile Home on Lake Magdalene Drive.