Thomas Pownall (bapt. 4 September 1722 (New Style) – 25 February 1805) was a British politician and colonial official. He was governor of the Province of Massachusetts Bay from 1758 to 1760, and afterward served in the British Parliament. He traveled widely in the North American colonies prior to the American Revolutionary War, and opposed Parliamentary attempts to tax the colonies. In the early 19th century he became an early advocate of the reduction or removal of trade barriers, and the establishment of a solid relationship between Britain and the United States.

John Adams wrote, "Pownall was the most constitutional and national Governor, in my opinion, who ever represented the crown in this province."

Thomas Pownall was the eldest son of William and Sarah (Burniston) Pownall. Baptised 4 September 1722 (New Style) in Lincoln, England, his father was a country gentleman and soldier whose poor health and early death in 1735 caused the family to fall upon hard times. Thomas was educated at Lincoln and at Trinity College, Cambridge, where he graduated in 1743. His education exposed him to classic and current philosophers, and the sciences. His first publication, a treatise on the origins of government published in 1752, began as notes developed at Cambridge.