There have been two baronetcies created for persons with the surname Thornhill, one in the Baronetage of England and one in the Baronetage of the United Kingdom. Both creations are extinct. The Thornhill Baronetcy, of Olantigh in the County of Kent and of Barbados, was created in the Baronetage of England on 24 December 1682 for Timothy Thornhill, the member of an old Kentish family. He was childless and the title became extinct on his death in circa 1693.