| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| HALCROW GILBERT ASSOCIATES LIMITED | 02312495 | 12/01/2015 | Dissolved |
| MECHANICAL AND ELECTRICAL DESIGN ASSOCIATES LIMITED | 00878811 | 12/01/2015 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| AMENTUM INTERNATIONAL NUCLEAR SERVICES LIMITED | 05532606 | 03/02/2017 | 03/06/2019 | Silver |
| BURDEROP INVESTMENTS LIMITED | 02485284 | 12/01/2015 | 19/06/2019 | Dissolved |
| CH2M HILL EUROPE LIMITED | 07262036 | 03/02/2017 | 03/06/2019 | One Red Flag |
| CH2M HILL SERVICES LIMITED | 04263139 | 03/02/2017 | 03/06/2019 | Strike Off |
| CH2M HILL UNITED KINGDOM | 02533469 | 03/02/2017 | 03/06/2019 | Silver |
| CROUCH HOGG WATERMAN LIMITED | SC136186 | 12/01/2015 | 03/06/2019 | Dissolved |
| HALCROW (CONSULTING ENGINEERS & ARCHITECTS) LIMITED | 01045458 | 12/01/2015 | 03/06/2019 | Amber |
| HALCROW ASIA LIMITED | 02458827 | 12/01/2015 | 03/06/2019 | One Red Flag |
| HALCROW ASIA PARTNERSHIP LIMITED | 02490667 | 12/01/2015 | 03/06/2019 | One Red Flag |
| HALCROW CANADA LIMITED | 05296410 | 12/01/2015 | 03/06/2019 | Dissolved |
| HALCROW CONSULTING LIMITED | 02326761 | 12/01/2015 | 03/06/2019 | One Red Flag |
| HALCROW GROUP LIMITED | 03415971 | 12/01/2015 | 03/06/2019 | Amber |
| HALCROW HOLDINGS LIMITED | 01674044 | 12/01/2015 | 03/06/2019 | One Red Flag |
| HALCROW INTERNATIONAL LIMITED | 02326765 | 12/01/2015 | 03/06/2019 | Amber |
| HALCROW INTERNATIONAL PARTNERSHIP | 02809680 | 12/01/2015 | 03/06/2019 | Amber |
| HALCROW RAIL APPROVALS LIMITED | 05079753 | 12/01/2015 | 03/06/2019 | Dissolved |
| HALCROW WATER SERVICES LIMITED | 03055857 | 12/01/2015 | 03/06/2019 | Dissolved |
| SIR WILLIAM HALCROW & PARTNERS LIMITED | 01722541 | 12/01/2015 | 03/06/2019 | Strike Off |
| TRANSMARK ASIA LIMITED | 02815214 | 12/01/2015 | 03/06/2019 | One Red Flag |
| YOLLES PARTNERSHIP LIMITED | 02333623 | 12/01/2015 | 03/06/2019 | Dissolved |