| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| BORDER RAIL TRAINING LIMITED | SC210195 | 23/08/2012 | Dissolved |
| CARILLION POWERLINES LIMITED | 08884783 | 04/04/2014 | Dissolved |
| EMEG GROUP LIMITED | 03366961 | 31/08/2010 | One Red Flag |
| GUILDSTONE ASSOCIATES LIMITED | 10678807 | 28/03/2017 | One Red Flag |
| POWER AND INFRASTRUCTURE RESOURCING LTD | 09274116 | 21/11/2014 | Gold |
| RAIL ACCESS PLATFORMS LIMITED | SC241895 | 23/08/2012 | Dissolved |
| SPL POWERLINES UK HOLDING LIMITED | SC355244 | 23/08/2012 | Not Trading |
| SPL POWERLINES UK LIMITED | SC202412 | 23/08/2012 | Silver |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| ALH RAIL COATINGS LIMITED | 03974438 | 23/04/2007 | 25/03/2011 | Dissolved |
| BINGHAM MANUFACTURING LIMITED | 02764733 | 03/10/2006 | 04/04/2007 | Dissolved |
| H. BINGHAM & SONS LIMITED | 03941841 | 02/10/2006 | 04/04/2007 | Dissolved |
| L.C. SWITCHGEAR LIMITED | 03829976 | 20/05/2014 | 03/03/2015 | Bronze |
| QUALTER, HALL & COMPANY LIMITED | 00112626 | 17/04/1998 | 30/04/1999 | One Red Flag |
| ROTEX EUROPE LTD | 04307924 | 19/10/2001 | 01/09/2002 | Silver |
| ROTEX EUROPE LTD | 04307924 | 01/05/2002 | 25/09/2006 | Silver |
| ROTEX JAPAN LIMITED | 05214894 | 26/08/2004 | 25/09/2006 | Bronze |
| SOLIDS HANDLING AND PROCESSING ASSOCIATION LIMITED | 01632503 | 11/07/2001 | 14/09/2006 | Gold |
| TMR BINGHAM LIMITED | 02888724 | 03/10/2006 | 06/03/2007 | Dissolved |