An only child, Tim Fountain was brought up in in a pub in the village of West Ardsley, West Yorkshire, where he lived with his parents and two goats, one of which had only three legs, before leaving to go to Hull University in 1987.

Tim Fountain's first major success was Resident Alien. Based on the life and writings of Quentin Crisp, starring Bette Bourne and directed by Mike Bradwell, the show opened at the Bush Theatre, London, in November 1999, transferring to New York Theatre Workshop in 2001 where it played a three month sell-out season and won two OBIE Awards (performance and design). The show subsequently won a Herald Angel at the Edinburgh Festival and toured across America, Australia and the UK. It has also been broadcast on BBC Radio 3.

In 2001 he directed the West End Production of Puppetry of the Penis. During this time he began an affair with the then-lesbian comedienne Jackie Clune who later went on to star in one of his plays. In the same year he was also a principal writer on Bob and Margaret (Channel Four/Comedy Central, USA).

Fountain hit the headlines when his one man show, Sex Addict opened at the Edinburgh Festival in 2004 before transferring to the Royal Court in 2005, and later the Schaubuehne, Berlin. During the show he solicited sexual partners on-line and the audience got to choose who he had sex with. The Daily Mail devoted an entire page to the show under the headline "Curtain Up on Depravity".

Fountain's other plays include Julie Burchill Is Away, starring Jackie Clune, Hotboi (or Deep Rimming in Poplar as it was called in Scotland) starring Bette Bourne, and the stage adaptation of Toby Young's book, How To Lose Friends and Alienate People starring Jack Davenport. In 2006 Fountain adapted the Oscar winning movie Midnight Cowboy for the stage starring Con O Neil and Charles Aitken. in 2008 his play about Rock Hudson and his agent Henry Willson, Rock, opened at the Oval House Theatre in London starring Bette Bourne as Hudson's agent Henry Willson and Michael Xavier as Hudson.

He has also written books. Quentin Crisp: a biography was published in 2002 by Absolute Press. So You Want to Be a Playwright?, his book on playwriting, was published by Nick Hern in 2007 and Rude Britannia, his book about the sex lives of the British was published by Weidenfeld and Nicolson in 2008. He has also written for numerous publications including The Guardian, The Sunday Times, "The Daily Mail", The Scotsman, Scotland on Sunday, The New Statesman and Attitude. Tim has appeared on Newsnight, Woman's Hour, Saturday Review and Loose Ends on BBC Radio Four and Weekender on BBC Radio 2. He has also presented a documentary about the death of Quentin Crisp for Channel Four.

He is a regular teacher of playwriting and has tutored for many organisations including The Central School of Speech and Drama, The Arvon Foundation and Dartmouth College in the USA. He was Literary Manager of the Bush Theatre from 1997 — 2001, and was Lecturer in Creative Writing at Strathclyde University from 2006-2009

Tim delights in political debate. In early April 2010 this resulted in a heated but ultimately amicable exchange in a London (Kings Cross) curry house with the former Liberal party election campaign manager.