| AMALGAMATED SMART METERING LIMITED09299892 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 8,746,013 | 100.00% | 100.00% | 100.00% | 2025-11-04 |
| WESTFIELD SM LIMITED09305317 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 8,746,012 | 100.00% | 100.00% | 100.00% | 2026-01-06 |
| RESERVE POWER TRADING LIMITED09548349 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 6,328,917 | 100.00% | 100.00% | 100.00% | 2026-04-05 |
| ILKESTON POWER LIMITED09806343 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 8,746,012 | 100.00% | 100.00% | 100.00% | 2025-10-02 |
| EXETER RP LIMITED09874992 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 5,610,383 | 100.00% | 100.00% | 100.00% | 2025-11-04 |
| MERCIA POWER RESPONSE (PRIVATE ROAD NO.5) LIMITED10217008 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-06-01 |
| MERCIA POWER RESPONSE (CHESTERFIELD ROAD) LIMITED10217080 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2026-06-01 |
| MERCIA POWER RESPONSE (ASHER LANE 2) LIMITED10217188 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2026-06-01 |
| MERCIA POWER RESPONSE (NOTTINGHAM ROAD) LIMITED10217239 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-06-01 |
| MERCIA POWER RESPONSE (PONTEFRACT ROAD) LIMITED10217285 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-06-01 |
| MERCIA POWER RESPONSE (WHITTINGTON ROAD) LIMITED10217287 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-06-01 |
| MERCIA POWER RESPONSE (SANDY LANE) LIMITED10269414 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-07-07 |
| MERCIA POWER RESPONSE (ALBION CLOSE) LIMITED10276812 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-07-12 |
| MERCIA POWER RESPONSE (CUCKOO ROAD) LIMITED10276822 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-07-12 |
| MERCIA POWER RESPONSE (MANNERS AVENUE 2) LIMITED10276831 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-07-12 |
| MERCIA POWER RESPONSE (THE WOOD YARD) LIMITED10276847 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-07-12 |
| MERCIA POWER RESPONSE (COMMON LANE) LIMITED10276850 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-07-12 |
| MERCIA POWER RESPONSE (OUTGANG LANE) LIMITED10276869 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-07-17 |
| MERCIA POWER RESPONSE (GRAPHITE WAY) LIMITED10279538 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2025-07-13 |
| DURHAM RP LIMITED11632552 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 939,223 | 100.00% | 100.00% | 100.00% | 2025-11-02 |
| MERCIA POWER RESPONSE (HALLAM WAY) LIMITED12395582 | Active | AUDIT EXEMPTION SUBSIDIARY | ORDINARY | 1 | 100.00% | 100.00% | 100.00% | 2026-01-08 |