| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| ELEAN POWER LIMITED | 02381529 | 13/10/2011 | Dissolved |
| First Choice Electricity Ltd | 03088766 | 23/07/1997 | Dissolved |
| First Choice Energi Ltd | 03088779 | 23/07/1997 | Dissolved |
| First Choice Gas Ltd | 03089176 | 23/07/1997 | Dissolved |
| First Choice Power Ltd | 03088742 | 23/07/1997 | Dissolved |
| Metgem Ltd | 02341195 | 14/08/2008 | Dissolved |
| NB POWER SERVICES (NO.1) LIMITED | 02380229 | 13/10/2011 | Dissolved |
| NB REAL ESTATE NO.1 LIMITED | 02377739 | 15/11/2010 | Dissolved |
| NORTH WEST WATER FINANCE LIMITED | 03263102 | 16/09/2010 | Dissolved |
| NORTH WEST WATER LIMITED | 03528619 | 16/09/2010 | Not Trading |
| NORTHERN HYDRO LIMITED | 02503927 | 13/10/2011 | Dissolved |
| North West Utilities Group Ltd | 02911183 | 17/11/1997 | Dissolved |
| North West Water Group Ltd | 02911184 | 17/11/1997 | Dissolved |
| Norweb Building Services Design Ltd | 02373214 | 17/11/1997 | Dissolved |
| Norweb Cable Communications Ltd | 02373224 | 17/11/1997 | Dissolved |
| Norweb Electricity Ltd | 02268727 | 17/11/1997 | Dissolved |
| Norweb Hydro Power (Glenridding) Ltd | 02654500 | 17/11/1997 | Dissolved |
| Norweb Power Marketing Ltd | 02381759 | 17/11/1997 | Dissolved |
| Norweb Powercom Ltd | 02379304 | 17/11/1997 | Dissolved |
| Norweb Security & Intruder Alarms Ltd | 02377755 | 17/11/1997 | Dissolved |
| Norweb Super Stores Ltd | 02379317 | 17/11/1997 | Dissolved |
| Norweb Supply Ltd | 03063718 | 17/11/1997 | Dissolved |
| Norweb Telecommunications Ltd | 02379725 | 17/11/1997 | Dissolved |
| SOUTH WEST STORES LIMITED | 02379722 | 16/09/2010 | Dissolved |
| UNITED UTILITIES (DORMANT SUBSIDIARIES) LIMITED | 02379714 | 16/09/2010 | Dissolved |
| UNITED UTILITIES COMMUNICATIONS LIMITED | 05556065 | 15/11/2010 | Dissolved |
| UNITED UTILITIES FINANCIAL SERVICES LIMITED | 05059812 | 15/11/2010 | Dissolved |
| UNITED UTILITIES HOLDINGS TRUSTEE LIMITED | 02816762 | 24/09/2010 | Dissolved |
| UNITED UTILITIES NOMINEES LIMITED | 02380261 | 16/09/2010 | Dissolved |
| UU DIRECTORATE LIMITED | 03354182 | 17/11/1997 | Dissolved |
| UU DIRECTORATE LIMITED | 03354182 | 31/07/2007 | Dissolved |
| UU GROUP LIMITED | 02594435 | 16/09/2010 | Not Trading |
| UU SECRETARIAT LIMITED | 03333298 | 17/11/1997 | Not Trading |
| UU SECRETARIAT LIMITED | 03333298 | 31/07/2007 | Not Trading |
| United Energy Sales Ltd | 02373216 | 17/11/1997 | Dissolved |
| United Energy Services Ltd | 02373404 | 17/11/1997 | Dissolved |
| United Utilities International (Holdings) Ltd | 02344586 | 17/11/1997 | Dissolved |
| United Utilities Quest Trustee Ltd | 03447566 | 02/04/2008 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| ESP NETWORKS LIMITED | 02865198 | 23/07/1997 | 01/03/2000 | Strike Off |
| JOBEN CONSULTING LIMITED | 10273038 | 12/07/2016 | 26/03/2019 | Bronze |
| Nb Hydro Power (Wales) Ltd | 03063716 | 17/11/1997 | 11/03/2002 | Dissolved |
| Nb Share Scheme Trustees Ltd | 02525003 | 28/01/1997 | 01/06/2000 | Dissolved |
| UNITED UTILITIES (DORMANT SUBSIDIARIES) LIMITED | 02379714 | 17/11/1997 | 01/06/2000 | Dissolved |
| UNITED UTILITIES (ESPS) PENSIONS TRUSTEE LIMITED | 02380227 | 17/11/1997 | 01/03/2000 | Dissolved |
| UNITED UTILITIES CONTRACT SOLUTIONS HOLDINGS LIMITED | 02381766 | 17/11/1997 | 01/06/2000 | Dissolved |
| UNITED UTILITIES MIDDLE EAST LIMITED | 03325273 | 14/08/2008 | 20/11/2008 | Dissolved |
| UNITED UTILITIES PROPERTY SERVICES LIMITED | 02380021 | 17/11/1997 | 01/06/2000 | Gold |
| UNITED UTILITIES PROPERTY SOLUTIONS (10010) LIMITED | 02377886 | 17/11/1997 | 01/06/2000 | Dissolved |
| UNITED UTILITIES TOTAL SOLUTIONS LIMITED | 02380133 | 17/11/1997 | 01/06/2000 | One Red Flag |
| UNITED UTILITIES TOTAL SOLUTIONS LIMITED | 02380133 | 16/09/2010 | 22/05/2013 | One Red Flag |
| UNITED UTILITIES UTILITY SOLUTIONS LIMITED | 02268728 | 17/11/1997 | 01/06/2000 | Dissolved |
| VEOLIA WATER OPERATIONAL SERVICES (TAY) LIMITED | 03354180 | 17/11/1997 | 08/11/1999 | Silver |
| VEOLIA WATER SOLUTIONS INDUSTRIAL OUTSOURCING UK LIMITED | 02917042 | 23/07/1997 | 01/06/2000 | Dissolved |