The BAFTA Award for Best Original Screenplay is the British Academy Film Award for the best script not based upon previously published material. It has been awarded since 1984.  In 1984 the category BAFTA Award for Best Screenplay was split into two awards, this one and the BAFTA Award for Best Adapted Screenplay.

Winners and nominees

1980s
1983: The King of Comedy – Paul D. Zimmerman
 Local Hero – Bill Forsyth
 Trading Places – Timothy Harris and Herschel Weingrod
 Zelig – Woody Allen

1984: Broadway Danny Rose – Woody Allen
 The Big Chill – Barbara Benedek and Lawrence Kasdan
 Comfort and Joy – Bill Forsyth
 A Private Function – Alan Bennett
 
1985: The Purple Rose of Cairo – Woody Allen
 Back to the Future – Bob Gale and Robert Zemeckis
 My Beautiful Laundrette – Hanif Kureishi
 Witness – William Kelley and Earl W. Wallace

1986: Hannah and Her Sisters – Woody Allen
 Crocodile Dundee – John Cornell, Paul Hogan and Ken Shadie
 The Mission – Robert Bolt
 Mona Lisa – Neil Jordan and David Leland

1987: Wish You Were Here – David Leland
 Hope and Glory – John Boorman
 Personal Services – David Leland
 Radio Days – Woody Allen

1988: A World Apart – Shawn Slovo
 Au revoir, les enfants – Louis Malle
 A Fish Called Wanda – John Cleese
 Moonstruck – John Patrick Shanley

1989: When Harry Met Sally... – Nora Ephron
 Dead Poets Society – Tom Schulman
 Rain Man – Ronald Bass and Barry Morrow
 Sex, Lies, and Videotape – Steven Soderbergh

1990s
1990: Cinema Paradiso (Nuovo cinema Paradiso) – Giuseppe Tornatore
 Crimes and Misdemeanors – Woody Allen
 Ghost – Bruce Joel Rubin
 Pretty Woman – J.F. Lawton

1991: Truly, Madly, Deeply – Anthony Minghella
 The Fisher King – Richard LaGravenese
 Green Card – Peter Weir
 Thelma & Louise – Callie Khouri

1992: Husbands and Wives – Woody Allen
 The Crying Game – Neil Jordan
 Hear My Song – Peter Chelsom and Adrian Dunbar
 Unforgiven – David Webb Peoples

1993: Groundhog Day – Harold Ramis and Danny Rubin 
 In the Line of Fire – Jeff Maguire
 The Piano – Jane Campion
 Sleepless in Seattle – Jeff Arch, Nora Ephron and David S. Ward

1994: Pulp Fiction – Roger Avary and Quentin Tarantino
 The Adventures of Priscilla, Queen of the Desert – Stephan Elliott
 Four Weddings and a Funeral – Richard Curtis
 Philadelphia – Ron Nyswaner

1995: The Usual Suspects – Christopher McQuarrie 
 Bullets Over Broadway – Woody Allen and Douglas McGrath
 Muriel's Wedding – P.J. Hogan
 Se7en – Andrew Kevin Walker

1996: Secrets & Lies – Mike Leigh
 Brassed Off – Mark Herman
 Fargo – Ethan and Joel Coen
 Lone Star – John Sayles
 Shine – Jan Sardi

1997: Nil by Mouth – Gary Oldman
 Boogie Nights – Paul Thomas Anderson
 The Full Monty – Simon Beaufoy
 Mrs. Brown – Jeremy Brock

1998: The Truman Show – Andrew Niccol
 Elizabeth – Michael Hirst
 Life Is Beautiful (La vita è bella) – Roberto Benigni and Vincenzo Cerami
 Shakespeare in Love – Marc Norman and Tom Stoppard

1999: Being John Malkovich – Charlie Kaufman
 All About My Mother (Todo sobre mi madre) – Pedro Almodóvar
 American Beauty – Alan Ball
 The Sixth Sense – M. Night Shyamalan
 Topsy-Turvy – Mike Leigh

2000s
2000: Almost Famous – Cameron Crowe
 Billy Elliot – Lee Hall
 Erin Brockovich – Susannah Grant
 Gladiator – David Franzoni, John Logan and William Nicholson
 O Brother, Where Art Thou? – Ethan and Joel Coen

2001: Amélie (Le fabuleux destin d'Amélie Poulain) – Jean-Pierre Jeunet and Guillaume Laurant  
 Gosford Park – Julian Fellowes and Steven Zaillian Kenneth Lonergan
 Moulin Rouge! – Baz Luhrmann and Craig Pearce
 The Others – Alejandro Amenábar
 The Royal Tenenbaums – Wes Anderson and Owen Wilson

2002: Talk to Her (Hable con ella) – Pedro Almodóvar
 And Your Mother Too (Y tu mamá también) – Alfonso and Carlos Cuarón
 Dirty Pretty Things – Steven Knight
 Gangs of New York – Jay Cocks Steven Zaillian Kenneth Lonergan
 The Magdalene Sisters – Peter Mullan

2003: The Station Agent – Thomas McCarthy
 21 Grams – Guillermo Arriaga
 The Barbarian Invasions (Les invasions barbares) – Denys Arcand
 Finding Nemo – Bob Peterson, David Reynolds and Andrew Stanton
 Lost in Translation – Sofia Coppola

2004: Eternal Sunshine of the Spotless Mind – Charlie Kaufman
 The Aviator – John Logan
 Collateral – Stuart Beattie
 Ray – James L. White
 Vera Drake – Mike Leigh

2005: Crash – Paul Haggis and Robert Moresco
 Cinderella Man – Akiva Goldsman and Cliff Hollingsworth
 Good Night, and Good Luck – George Clooney and Grant Heslov
 Hotel Rwanda – Terry George and Keir Pearson
 Mrs Henderson Presents – Martin Sherman

2006: Little Miss Sunshine – Michael Arndt
 Babel – Guillermo Arriaga
 Pan's Labyrinth (El laberinto del fauno) – Guillermo del Toro
 The Queen – Peter Morgan
 United 93 – Paul Greengrass

2007: Juno – Diablo Cody
 American Gangster – Steven Zaillian
 The Lives of Others (Das Leben der Anderen) – Florian Henckel von Donnersmarck
 Michael Clayton – Tony Gilroy
 This Is England – Shane Meadows

2008: In Bruges – Martin McDonagh
 Burn After Reading – Ethan and Joel Coen
 Changeling – J. Michael Straczynski
 I've Loved You So Long (Il y a longtemps que je t'aime) – Philippe Claudel
 Milk – Dustin Lance Black

2009: The Hurt Locker – Mark Boal
 The Hangover – Jon Lucas and Scott Moore
 Inglourious Basterds – Quentin Tarantino
 A Serious Man – Joel Coen and Ethan Coen
 Up – Pete Docter and Bob Peterson

2010s
2010: The King's Speech – David Seidler
 Black Swan – Mark Heyman, Andrés Heinz and John McLaughlin
 The Fighter – Scott Silver, Paul Tamasy and Eric Johnson
 Inception – Christopher Nolan
 The Kids Are All Right – Lisa Cholodenko and Stuart Blumberg

2011: The Artist – Michel Hazanavicius
 Midnight in Paris – Woody Allen
 The Guard – John Michael McDonagh
 The Iron Lady – Abi Morgan
 Bridesmaids – Annie Mumolo, Kristen Wiig

Other websites
 

BAFTA Awards