William Ash, (born 13 January 1977) is a British TV and film actor. His appearances include Mad About Mambo, Lilies, Burn It, All the King's Men, A Midsummer Night's Dream, Doctor Who and more recently Hush and Waterloo Road. He began his career in the ITV series Where the Heart Is. His stage credits include the premiere production of How to Disappear Completely and Never Be Found with Sheffield Theatres. In 2009, Ash played the leading role of "Zakes Abbott" in the British horror film HUSH. Ash also has minor roles in programmes such as Coronation Street and has completed voice-over work for TV advertisements. He also appeared in Heartbeat back in 1992 where he played a cheeky school boy for one episode. He is currently playing Deputy Headteacher 'Chris Mead' in Waterloo Road. On 12th April 2011, Ash played a young Yuri Gagarin in the BBC Radio 4 Afternoon Play; Titatium, broadcast in honour of the 50th anniversary of the first manned flight into space.

He prefers to be known as "Will".

His second cousin is Peter Ash, who is also an actor.