Bonneville was born Hugh Richard Bonneville Williams in London, England. He studied at Sherborne School and read theology at Corpus Christi College, Cambridge before training for the stage at the Webber Douglas Academy of Dramatic Art in London. He has been married to artist Lulu Evans since 4 November 1998, and they have one child together.

Bonneville's first professional stage appearance was at the Open Air Theatre, Regent's Park. In 1987 he joined the National Theatre where he appeared in several plays, then the Royal Shakespeare Company in 1991, where he played Laertes to Kenneth Branagh's Hamlet (1992 — 1993).

He was also Valentine in The Two Gentlemen of Verona, Bergetto in 'Tis Pity She's a Whore, Kastril and later Surly in The Alchemist. He worked with Sam Mendes, a contemporary of his at Cambridge.

He made his television debut in 1991, billed as Richard Bonneville. His early roles were usually good-natured bumbling characters like Bernie in Notting Hill and Mr. Rushworth in Mansfield Park.

In the BBC television series, Take A Girl Like You (2000) and Armadillo (2001), he played more villainous characters, leading up to the domineering Henleigh Grandcourt in Daniel Deronda (2002) and the psychopathic killer James Lampton in The Commander (2003).

In Love Again, he played the poet Philip Larkin. In 2004, he played Sir Christopher Wren in the docudrama Wren – The Man Who Built Britain.

Many say his best achievement to date was his performance as the young John Bayley opposite Kate Winslet in Iris, his performance lauded by critics.