Fifteen to One is a popular general knowledge quiz show on Channel 4 in the United Kingdom. Since its inception in 1988 it has been presented and produced by William G. Stewart. To date some 30,000 contestants have appeared on the show.

The format of the show, developed by John Lewis of Regent Productions originally involved 20 starting contestants but the figure cut down to 15 in order to fit a running time of just under 30 minutes. Most of John's Lewis's format remained unchanged when the show eventually aired.

Each series consists of a number of heats and a grand final. After the last heat the 15 winning players with the highest scores compete in the grand final.

The quiz itself consists of two phases. In the first phase contestants are eliminated from the competition until three remain. At this point the show is interrupted for a commercial break. Following the break two further contestants are eliminated to leave the competition winner.

The first phase

The first phase of the quiz involves reducing the number of contestants from fifteen to three. This takes place over three rounds of questioning.

The first two rounds of questioning

Fifteen numbered contestants begin the quiz with three lives. Each contestant in numerical order is asked a general knowledge question and given a period of five seconds to give a correct answer. If they fail to answer the question correctly they lose one of their three lives. After all of the 15 contestants have been asked a question, another round of questioning begins. If a player begins this second round of questioning with all of their lives intact and fails to give a correct answer to their second question they lose one of their three remaining lives; however, if a player lost a life in the first round and they fail to answer their second question correctly they lose both of their remaining two lives and are eliminated from the competition.

The third round of questioning

It should be noted that at the beginning of this stage that each contestant will have either 2 or 3 lives remaining. The third round of questioning begins with the lowest numbered contestant being asked a question. If the player fails to answer the question correctly the player loses a life and play passes to the next numbered player. Each player that gives a correct answer must nominate one of the remaining players to answer the next question. If a nominated player does not give a correct answer he loses a life and the player who made the nomination must nominate again (he may nominate the same player again). When a contestant loses their final life they are eliminated from the competition. When only three contestants remain the first phase of the quiz is over and the programme pauses for a commercial break.

The second phase

During the second phase 40 questions will be asked, each of which is worth 10 points. The three contestants are restored to the full set of 3 lives and the number of lives that each player had remaining at the end of the previous round becomes part of player's score. Thus those contestants who had 3 lives left will start the second phase with a score of 3 etc. The first question is open to all players to answer and the contenstants must press a buzzer in order to give their answer. If after buzzing they fail to answer the question correctly a life is lost and another question is asked on the buzzer. Once one of players has answered 3 questions correctly they are given the opportunity to answer the next question themselves or nominate one of the other two players to answer. From this point on, after each successfully answered question the host will ask - "Question or nominate?". If a nominated player fails to answer a question correctly, the player who made the nomination again has a choice of question or nominate?. If a player chooses to answer a question themselves and fails to answer it correctly the next question is asked on the buzzer. Once all 40 questions have been asked, or the last remaining player has lost all of his lives, any lives that remain are added to the surviving players' score with a value of 10 points each. The surviving player with the highest score is declared the winner. A maximum score of 433 can be achieved if a player starts the second phase with all three lives intact and correctly answers all 40 questions. The player scores 3 points for retaining 3 lives from the first phase, 400 points for answering 40 questions correctly and 30 points for retaining 3 lives from the end of the first phase. The maximum score has been achieved only once by Bill McKaig, a minister from Glasgow. The feat of answering all 40 third round questions correctly was also achieved by Daphne Fowler and Michael Penrice who both finished with a score of 432. If the winner of the show has a final score high enough, his name is placed on the finals board (possibly knocking another winning contestant off of the board).

At the end of the series those people whose names remain on the finals board compete in the grand final. All of players who won their heat are allowed to re-enter the contest in the following series whilst the other players are barred from re-entering for a number of years.

The grand final of the first series of 2003 saw the first ever tie in the shows history. No provision had been made for a tie breaker.

The series prize tends to be a classical artefact (for example a Greek vase), and is presented to the winning contestant by Laura Calland, the regular voice-over artist. Calland's voice-overs are occasionally provided by other presenters, usually Philip Lowrie, but only Calland is seen on screen, when she presents the prize.

Past winners of Fifteen to One

Series Grand Final Winner Top of the Finals Board Score Shown
1 Jon Goodwin Peter Knott 270 1988
2 Mal Collier Fred Gavin 290
3 Kevin Ashman Mal Collier 261 1989
4 Andrew Francis Thomas Dyer 202
5 Anthony Martin Anthony Martin 251 1990
6 Mike Kirby Mike Kirby 281
7 Thomas Dyer Mike Kirby 263 1991
8 Anthony Martin Katharine Heaney 242
9 Julian Allen Barbara Thompson 252 1992
10 Barbara Thompson Sheri Evans 231
11 Anthony Martin Tim Goadby 242 1993
12 Glen Binnie Andrew McGlennon 302
13 Stanley Miller Peter Fillingham 251 1994
14 Leslie Booth Lesley Webster 262
15 Leslie Booth Christopher Cooke 292 1995
16 Ian Potts Susan 'O Donoghue 231
17 Arnold O’ Hara John Clarke 291 1996
18 Martin Riley Martin Riley 333
19 Trevor Montague Christopher Bostock 292 1997
20 Bill Francis Rosemary Broome 311
21 Nick Terry Christopher Bostock 272
22 Nick Terry Bill McKaig 272 1998
23 Bill McKaig Roy Smith 293
24 Paul Hillman Michael Irwin 311
25 Nick Terry Bill McKaig 433 1999
26 Nick Terry Michael Penrice 321
27 Les Arnott John Jenkins 303 2000
28 Dag Griffiths Daphne Fowler 432
29 Matti Watton Daphne Fowler 383
30 Daphne Fowler Daphne Fowler 333 2001
31 Daphne Fowler Martin Saunders 292
32 Matti Watton Michael Penrice 423 2002
33 David Good ? ?
34 Jack Welsby
David Stedman
Azeez Feshitan ? 2003