(1) | 51.61 | CBP | Omari Carr-Miller | (Croydon Harriers) | 1 FINAL | Kingsmeadow Stadium | 9 May 2009 |
(2) | 51.7 | CBP | David McKenzie | (Croydon Harriers) | 1 FINAL | Croydon Arena | 28 April 1985 |
(3) | 52.28 | | Sylvester Akpalara | (Herne Hill Harriers / (StM&AA)) | 1 FINAL | Kingsmeadow Stadium | 10 May 2008 |
(4) | 52.9 | | Stephen Mitchell | (Epsom & Ewell Harriers) | 1 FINAL | Kingsmeadow Stadium | 3 May 1992 |
(5) | 53.2 | | Richard Holt | (Blackheath Harriers) | 1 FINAL | Tooting Bec | 27 April 1986 |
(6) | 53.30 | | Precious Ojighoro | (Herne Hill Harriers) | 1 FINAL | Kingsmeadow Stadium | 15 May 2004 |
(7) | 53.4 | | Austin Ferns | (Hercules Wimbledon AC) | 1 FINAL | Stompond Lane, Walton | 2 July 1995 |
(8) | 53.6 | CBP | D Batchelor | (Guildford & Godalming AC) | HEATS | Motspur Park | 3 June 1975 |
(9) | 53.7 | | Keith Wu | (Croydon Harriers) | 1 FINAL | Croydon Arena | 16 May 1993 |
(10) | 53.8 | | D Batchelor | (Guildford & Godalming AC) | 1 FINAL | Motspur Park | 7 June 1975 |
(11) | 53.9 | | Rikkie Letch | (Aldershot, Farnham & District AC) | 1 FINAL | Kingsmeadow Stadium | 12 May 2007 |
(12) | 53.99 | | Sylvester Akpalara | (Herne Hill Harriers / (StM&AA)) | 1h1 HEAT 1 | Kingsmeadow Stadium | 10 May 2008 |
(13) | 54.02 | | Joash Howard | (Croydon Harriers) | 1 FINAL | Kingsmeadow Stadium | 13 May 2006 |
(14) | 54.07 | | Shaun Cooke | (Sutton & District AC) | 1 FINAL | Kingsmeadow Stadium | 14 May 2011 |
(15) | 54.2 | | David McKenzie | (Croydon Harriers) | 1 HEAT 1 | Croydon Arena | 28 April 1985 |
(16) | 54.22 | | Joash Howard | (Croydon Harriers) | 1 HEAT 1 | Kingsmeadow Stadium | 13 May 2006 |
(17) | 54.3 | | Wayne Tarquini | (Herne Hill Harriers / StockwellMS) | 1 FINAL | Motspur Park | 5 June 1971 |
(18) | 54.5 | | David Bond | (Woking AC) | 2 FINAL | Tooting Bec | 27 April 1986 |
| 54.5 | | David Moulton | (South London Harriers) | 2 FINAL | Stompond Lane, Walton | 2 July 1995 |
| 54.5 | | Moyo Sankofa | (Herne Hill Harriers) | 1 FINAL | Kingsmeadow Stadium | 13 May 2001 |
(21) | 54.62 | | George Munt | (Sutton & District AC) | 2 FINAL | Kingsmeadow Stadium | 9 May 2009 |
(22) | 54.7 | | I Moriarty | (Wallington High School) | 1 FINAL | Motspur Park | 10 June 1972 |
(23) | 54.8 | | J Robinson | (Croydon Harriers) | 1 HEAT 2 | Tooting Bec | 27 April 1986 |
| 54.8 | | Gary Parker | (Aldershot, Farnham & District AC) | 1 FINAL | Kingsmeadow Stadium | 26 July 1997 |
| 54.8 | | Precious Ojighoro | (Herne Hill Harriers) | 1 FINAL | Kingsmeadow Stadium | 10 May 2003 |
(26) | 55.0 | | Kevin Fitzpartick | (Croydon Harriers) | 1 FINAL | Croydon Arena | 24 April 1983 |
(27) | 55.02 | | Samuel A-Kissi | (Herne Hill Harriers) | 1 FINAL | Kingsmeadow Stadium | 11 May 2002 |
(28) | 55.1 | | M Brockington | (Kent AC) | 1 FINAL | Motspur Park | 14 May 1977 |
| 55.1 | | Stephen Green | (Guildford & Godalming AC) | 1 FINAL | Stompond Lane, Walton | 16 June 1996 |
| 55.1 | | Kevin Cayley | (unattached) | 2 FINAL | Stompond Lane, Walton | 16 June 1996 |
(31) | 55.3 | | J Veglio | (John Fisher School, Purley) | 2 FINAL | Motspur Park | 10 June 1972 |
| 55.3 | | S J Ward | (Hercules Wimbledon AC) | 1 HEAT 1 | Motspur Park | 29 April 1978 |
| 55.3 | | Paul Roberts | (Mitcham AC) | 1 FINAL | Croydon Arena | 29 April 1984 |
| 55.3 | | P Hull | (Woking AC) | 3 FINAL | Tooting Bec | 27 April 1986 |
(35) | 55.39 | | Burton Dredge | (Herne Hill Harriers) | 2 FINAL | Kingsmeadow Stadium | 13 May 2006 |
(36) | 55.4 | | Robert Milner | (Belgrave Harriers) | 2 FINAL | Kingsmeadow Stadium | 3 May 1992 |
| 55.4 | | Eshref Hassan | (Belgrave Harriers) | 1 FINAL | Croydon Arena | 14 May 1994 |
(38) | 55.41 | | Lewis Lloyd | (Herne Hill Harriers) | 2 FINAL | Kingsmeadow Stadium | 10 May 2008 |
(39) | 55.5 | | P Blezard | (Kings College School, Wimbledon) | 2 FINAL | Motspur Park | 5 June 1971 |
| 55.5 | | David Bond | (Woking AC) | 1 HEAT 3 | Tooting Bec | 27 April 1986 |
| 55.5 | | J Robinson | (Croydon Harriers) | 4 FINAL | Tooting Bec | 27 April 1986 |
| 55.5 | | Richard Aspden | (Epsom & Ewell Harriers) | 1 FINAL | Kingsmeadow Stadium | 21 April 1991 |
| 55.5 | | Jamal Dyce | (Croydon Harriers) | 2 FINAL | Kingsmeadow Stadium | 10 May 2003 |
(44) | 55.58 | | Patrick Lucas | (Croydon Harriers) | 1 FINAL | Kingsmeadow Stadium | 8 May 2010 |
(45) | 55.6 | | Richard Vassall | (Guildford & Godalming AC) | 1 FINAL | Motspur Park | 26 April 1980 |
| 55.6 | | A Ross | (Belgrave Harriers) | 5 FINAL | Tooting Bec | 27 April 1986 |
| 55.6 | | Stephen Green | (Guildford & Godalming AC) | 1 HEAT 1 | Stompond Lane, Walton | 16 June 1996 |
| 55.6 | | Andrew Jenner | (Croydon Harriers) | 1 FINAL | Kingsmeadow Stadium | 9 May 1998 |
| 55.6 | | James Clement | (Camberley & District AC) | 3 FINAL | Kingsmeadow Stadium | 10 May 2003 |
(50) | 55.61 | | Richard Smeaton | (Kingston AC & Polytechnic Harriers) | 3 FINAL | Kingsmeadow Stadium | 13 May 2006 |
|
50 performances of 55.61 or better. |