Sir Philip Courtenay (c. 1355 – 29 July 1406), of Powderham, Devon was the fifth son of Hugh Courtenay, 10th Earl of Devon (1303–1377). He was the founder of the cadet dynasty known as "Courtenay of Powderham", seated at the manor of Powderham, until then a former Bohun manor of little importance, whilst the line descended from his elder brother, the Earls of Devon of the mediaeval era, continued to be seated at Tiverton Castle and Okehampton.