| Accord Energy Ltd | 2877398 | Millstream, Maidenhead Road, Windsor, SL4 5GD, England |
| Axis Telecoms Limited | 04343227 | Suite E, Shirethorn House, Prospect Street, Hull, HU2 8PX, England |
| BES Commercial Electricity Limited | 6882734 | 3 Darwin Court, Hawking Place, Bipsham, Blackpool, FY02 0JW, England |
| Better Energy Supply Ltd | 7176401 | 68 Musters Road, West Bridgford, Nottingham, NG2 7PR, England |
| Bizzenergy Ltd | 3961223 | BizzEnergy House, Brook Court, Whittington Road, Worcester, WR5 2RX, England |
| British Energy Direct Ltd | 4935015 | Barnett Way, Barnwood, Gloucester, GL4 3RS, England |
| British Gas Trading Ltd (BGAS) | 3078711 | Millstream, Maidenhead Road, Windsor, SL4 5GD, England |
| British Gas Trading Ltd (ENRD) | 3078711 | Millstream, Maidenhead Road, Windsor, SL4 5GD, England |
| Co-Operative Energy Limited | 6993470 | Co-operative House, 234 Botley Road, Oxford, OX2 0HP, England |
| Dual Energy Direct Limited | 0646 8946 | 4th Floor, Premium House, The Esplanade, Worthing, BN11 2BJ, England |
| E.ON Energy Ltd | 3407430 | Westwood Business Park, Westwood Way, Coventry, CV4 8LG, England |
| E.ON UK CHP Plc | 2684288 | Westwood Way, Westwood Business Park, Coventry, CV4 8LG, England |
| E.ON UK Plc | 2366970 | Westwood Way, Westwood Business Park, Coventry, CV4 8LG, England |
| Eastern Power Networks plc | 2366906 | Newington House, 237 Southwark Bridge Road, London, SE1 6NP, England |
| Economy Energy Trading Limited | 07513319 | Rapide House, Siskin Parkway West, Middlemarch Business Park, Coventry, CV3 4PB, England |
| Economy Power Ltd | 3385578 | Westwood Way, Westwood Business Park, Coventry, CV4 8LG, England |
| EDF Energy Customers Plc | 2228297 | 40 Grosvenor Place, Victoria, London, SW1X 7AW, England |
| Electricity Direct (UK) Ltd | 3174056 | Millstream, Maidenhead Road, Windsor, SL4 5GD, England |
| Electricity North West Limited | 2366949 | 304 Bridgewater Place, Birchwood Park, Warrington, WA3 6XG, England |
| Electricity Plus Supply Limited | 5199936 | Dryden House, The Edge Business Centre, Hunber Road, London, NW2 6EW, England |
| Eneco Energy Trade BV | 30167836 | 8th Floor, Rivium Quadrant 75, 75 2909 LC, Capelle Aan Den Ijssel, ROTTERDAM, 2909C, The Netherlands |
| Energetics Electricity Ltd | SC234694 | Energetics Electricity Ltd, International House, Stanley Boulevard, Hamilton International Technology Park, High Blantyre, Glasgow, G72 0BN, Scotland |
| Energy 2 Sell Limited | 07027177 | c/o Gilmond Consulting Ltd, Richmond House, Richmond Hill, Bournemouth, BH2 6EQ, England |
| Energy COOP Ltd | 6053905 | Tower House, Parkstone Rd, POOLE, BH15 2JH, England |
| Energy Data Company Limited | 4741972 | Hurst House, 131-133 New London Road, Chelmsford, CM2 0QT, England |
| Energyco2 Ltd | 5095555 | 3 Radian Court, Knowlhill, Milton Keynes, MK5 8PJ, England |
| ESP Electricity Limited. | 4718806 | Hazeldean, Station Road, Leatherhead, KT22 7AA, England |
| Esso Petroleum Co Ltd | 00026538 | ExxonMobil House, Ermyn Way, Leatherhead, KT22 8UX, England |
| First Utility Limited | 5070887 | 19 South Audley Street, London, W1K 2NU, England |
| Garsington Energy Limited | 07109264 | 6 Peerglow Centre, Marsh Lane, Ware, Hertfordshire, SE12 9QL, England |