He was born on 20 May 1961 in North Cornelly, and trained at Guildford School of Acting. He made his television debut in 1984 in BBC drama The Mimosa Boys, about the Falklands War, and a year later starred Doctor Who two-parter, Vengeance On Varos.

In 1986 he starred as Ham Peggotty in a television adaptation of Charles Dickens' David Copperfield, and in 1987 in a number of episodes of science fiction drama Knights Of God.

Teale appeared in the 1989 adaptation of Dickens' Great Expectations alongside John Rhys-Davies and Anthony Hopkins and in 1990 he took on the role of Detective Sergeant Mike McCarthy in police drama series Waterfront Beat.

In 1991 he starred in two productions by the Royal Shakespeare Company; playing Hotspur in Henry IV part 1 and Mark Antony in Julius Caesar. 1991 also saw the release of John Irvin's Robin Hood in which he starred as Will Scarlett.

Further Shakespearean roles followed in 1993 in Love's Labour's Lost and The Merchant Of Venice.

In 1996 he starred in the BBC's production of Arthur Miller's Death Of A Salesman, in single episodes of Dangerfield and the Ruth Rendell Mysteries.

Teale swapped the small screen for the stage in 1997 when he took on the role of Torvald Helmer in a production of Henrik Ibsen's A Doll's House. He gained critical acclaim, and won Broadway's 1997 Tony Award for best actor in a featured role and was nominated for a 1997 Laurence Olivier Theatre Award for best actor in a supporting role.

He joined the cast of BBC hit drama Ballykissangel in 1999 and also appeared in a film adaptation of Anton Chekhov's The Cherry Orchard. In 2001 Teale starred in television film Conspiracy alongside Kenneth Branagh and Stanley Tucci which dramatized the 1942 Wannsee Conference.

Teale starred with Dawn French in television comedy Ted And Alice in 2002, and James Nesbitt in crime drama Murphy's Law in 2005. He has made brief appearances in many other hit television series such as Spooks, Midsomer Murders, Torchwood and Lewis.