| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| Equalorder Limited | 02534549 | 24/08/1991 | Dissolved |
| Scx Two Limited | 02475632 | 28/02/1991 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| B M Scotland (1993) Ltd | 02574893 | 01/09/1993 | 05/03/1994 | Dissolved |
| B M Scotland Ltd | 02688838 | 01/09/1993 | 05/03/1994 | Dissolved |
| Community Leisure Management Ltd | 02163239 | 12/09/1992 | 08/09/1994 | Dissolved |
| Euroserv Ltd | 01562858 | 05/03/1993 | 12/03/1994 | Dissolved |
| I A L Ltd | 01630799 | 05/03/1993 | 12/03/1994 | Dissolved |
| International Aeradio Consultancy Services Ltd | 00952762 | 05/03/1993 | 12/03/1994 | Dissolved |
| International Aeradio Ltd | 01485659 | 05/03/1993 | 12/03/1994 | Dissolved |
| Prime Contractors Ltd | 02378246 | 02/05/1991 | 10/10/1994 | Dissolved |
| SERCO EUROPE LIMITED | 00451392 | 20/04/1992 | 12/03/1994 | Dissolved |
| SERCO GROUP PLC | 02048608 | 25/04/1992 | 22/10/1997 | Silver |
| SERCO GULF ENGINEERING LIMITED | 02809869 | 24/06/1993 | 06/04/1994 | Dissolved |
| SERCO INTERNATIONAL LIMITED | 02324094 | 01/12/1991 | 12/03/1994 | Silver |
| SERCO LIMITED | 00242246 | 24/04/1992 | 05/03/1994 | Silver |
| SERCO REGIONAL SERVICES LIMITED | 01653016 | 19/02/1993 | 01/07/1994 | One Red Flag |
| SERCO-IAL LIMITED | 00427272 | 30/04/1992 | 12/03/1994 | Silver |
| Sercair Ltd | 02602477 | 17/04/1992 | 12/03/1993 | Dissolved |
| Serco Aviation Services Ltd | 01538157 | 05/03/1993 | 12/03/1994 | Dissolved |
| Serco Consultants Ltd | 02186483 | 24/04/1991 | 31/12/1994 | Dissolved |
| Serco Contracting Ltd | 02435848 | 25/10/1991 | 10/10/1994 | Dissolved |
| Serco Development Services Ltd | 00592499 | 05/03/1993 | 12/03/1994 | Dissolved |
| Serco Education Ltd | 02109225 | 24/04/1991 | 12/03/1994 | Dissolved |
| Serco Facilities Management Ltd | 02517692 | 03/07/1991 | 18/08/1994 | Dissolved |
| Serco Field Services Ltd | 02050174 | 20/04/1992 | 01/07/1994 | Dissolved |
| Serco Government Central Services Ltd | 02756646 | 20/10/1992 | 10/10/1994 | Dissolved |
| Serco Health Services Ltd | 02478475 | 08/03/1992 | 10/10/1994 | Dissolved |
| Serco Inactive 1 Ltd | 02269522 | 20/04/1992 | 12/03/1994 | Dissolved |
| Serco Inactive 4 Ltd | 00850447 | 05/03/1993 | 12/03/1994 | Dissolved |
| Serco International Fire Training Centre Ltd | 01563367 | 05/03/1993 | 12/03/1994 | Dissolved |
| Serco International Services Ltd | 02568815 | 14/12/1991 | 06/01/1997 | Dissolved |
| Serco Leisure Ltd | 02202587 | 28/12/1991 | 10/10/1994 | Dissolved |
| Serco Maintenance Services Ltd | 02674902 | 19/02/1993 | 10/10/1994 | Dissolved |
| Serco Management Ltd | 02107698 | 24/04/1991 | 31/12/1996 | Dissolved |
| Serco Operations Ltd | 01858592 | 20/04/1992 | 10/10/1994 | Dissolved |
| Serco Quality & Safety Services Ltd | 02475633 | 28/02/1992 | 10/10/1994 | Dissolved |
| Serco Research & Development Ltd | 02736437 | 01/08/1992 | 01/09/1994 | Dissolved |
| Serco Resource Management Ltd | 02213159 | 31/03/1992 | 10/10/1994 | Dissolved |
| Serco Services Ltd | SC145051 | 21/06/1993 | 05/03/1994 | Dissolved |
| Serco Skysafe Limited | 02496715 | 27/04/1991 | 10/10/1994 | Dissolved |
| Serco Southall Services Ltd | 02054685 | 24/04/1991 | 05/05/1994 | Dissolved |
| Serco Systems Ltd | 01861237 | 20/04/1992 | 30/04/1994 | Dissolved |
| Sercoserve Ltd | 02497013 | 27/04/1991 | 16/09/1994 | Dissolved |
| Superbusy Ltd | 02533020 | 21/08/1991 | 04/08/1994 | Dissolved |
| Technical & Logistic Services Ltd | 02624410 | 29/09/1993 | 13/06/1994 | Dissolved |
| Traffic Information Services Ltd | 02429339 | 05/10/1991 | 01/07/1994 | Dissolved |