Harry Frederick Gerard Hadden-Paton (born 10 April 1981) is a British actor. He is perhaps best known for his television roles as Herbert Pelham, 7th Marquess of Hexham, in the television series Downton Abbey and Martin Charteris in The Crown.

Hadden-Paton played the lead role of Henry Higgins in the Lincoln Center Theater revival of My Fair Lady on Broadway, a performance for which he was nominated for the 2018 Tony Award for Best Actor in a Musical. Hadden-Paton was born at Westminster Hospital in London, the son of former cavalry officer Nigel Hadden-Paton, head of a landed gentry family of Rossway, near Berkhamsted, Hertfordshire, and Sarah ('Bumble'), daughter of Brigadier Frederick Mellor, of The Cottage, Chiddingfold, Surrey. He has three sisters: Polly, Clementine, and Alice.