| Name | Year | Details |
| Paul Jackson | 1979 | |
| Marian Jago | 2005 | |
| Alwyn James | 1976 | |
| Bill James | 1984 | |
| Gary James | 2003 | |
| Rosemary James | 1978 | Champion |
| Madeline Jan | 1974 | |
| Ivor Jeffery-Machin | 1975 | Semi-finalist |
| Adrian Jeffs | 1988 | |
| 2004 | ||
| Hadrian Jeffs | 2005 | Finalist |
| Philip Jenkins | 1979 | Champion |
| Sue Jenkins | 1977 | Finalist |
| Christopher Joby | 2003 | |
| Richard Joby | 1984 | Finalist |
| Brian John | 1988 | |
| Jennifer Johnson | 1975 | |
| Kathryn Johnson | 1978 | as Kathryn Jones |
| 1995 | ||
| Roy Johnson | 1974 | |
| Stuart Johnson | 1993 | Semi-finalist |
| George Johnson | 1975 | Finalist |
| Richard Johnston | 2004 | |
| Barry Jones | 1979 | Semi-finalist |
| Byron Jones | 1984 | Semi-finalist |
| Caroline Jones | 1994 | |
| Chris Jones | 2001-2 | |
| 2003 | ||
| D Jones | 1972 | |
| David Jones | 2004 | |
| Dick Jones | 1989 | Finalist |
| Dyfrig Jones | 2003 | |
| Gethin Jones | 1992 | |
| 1998 | Semi-finalist | |
| Graeme Jones | 1993 | |
| 1999 | Semi-finalist | |
| Margaret Jones | 1993 | |
| Olivier Jones | 1996 | |
| Robert Jones | 1995 | Finalist |
| 1998 | ||
| Phil Jordan | 2004 |