| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| ALDERBROOK ENERGY LIMITED | 11051142 | 07/11/2017 | Dissolved |
| CWMNI EGINO LIMITED | 13475029 | 18/03/2022 | Bronze |
| STROLLERS REACH (FREEHOLD) LIMITED | 11500801 | 19/11/2021 | Gold |
| THE ALDERBROOK PARK MANAGEMENT COMPANY LIMITED | 03311885 | 05/06/2023 | Gold |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| BRADWELL POWER GENERATION COMPANY LIMITED | 09941394 | 18/01/2019 | 30/11/2021 | Silver |
| BRADWELL POWER HOLDING COMPANY LIMITED | 09940504 | 21/03/2019 | 30/11/2021 | Silver |
| ENERGY NETWORKS ASSOCIATION LIMITED | 04832301 | 01/02/2007 | 07/09/2009 | Bronze |
| HORIZON NUCLEAR POWER WYLFA HOLDINGS LIMITED | 09641958 | 01/07/2015 | 01/05/2016 | Bronze |
| HORIZON NUCLEAR POWER WYLFA LIMITED | 06811987 | 01/07/2015 | 01/05/2016 | Bronze |
| NORTHMERE LIMITED | 03232826 | 01/02/2007 | 07/09/2009 | Amber |
| NUCLEAR INDUSTRY ASSOCIATION | 02804518 | 02/12/2009 | 30/11/2016 | Silver |
| SIFA FIRESIDE | 03094905 | 10/07/2008 | 18/03/2010 | Bronze |
| SIZEWELL C LIMITED | 09284825 | 03/04/2019 | 30/11/2021 | Silver |