Thomas Beaufort, Duke of Exeter (c. January 1377 – 31 December 1426) was an English military commander during the Hundred Years' War, and briefly Chancellor of England.

During this time, Henry V began a policy of creating Norman titles for his aristocrats, with Beaufort being made Count of Harcourt in 1418.

The next year he was captured at the Battle of Baugé, where his nephew, Thomas of Lancaster, 1st Duke of Clarence, was killed.

The Duchy of Exeter was restored to the Holland family; the Earldom of Dorset was recreated for Edmund, Count of Mortain, his nephew.

As a legitimated grandson of the sovereign, Beaufort bore the arms of the kingdom, differenced by a bordure gobony azure and ermine.