| Saint-Gobain Isover UK |
| Salford City Council |
| SanLamere (UK) Ltd |
| sapratings.com |
| SBGI |
| SCARF |
| Schools & Home Energy Education Project |
| Scientific Homes |
| Scottish and Southern Energy |
| Scottish Association of Landlords |
| Scottish Federation of Housing Associations |
| Scottish Gas |
| Scottish Government |
| Scottish Power |
| SE2 |
| Seeboard Energy plc |
| SEEDA |
| Self Energy Ltd |
| Senator Energy Services Ltd |
| Severn Wye Energy Agency |
| SGN Commercial Services |
| Sheffield City Council |
| Shropshire County Council |
| Skyreach Systems |
| SNIPEF |
| Sohn Associates |
| Solaglas |
| Solar Bright |
| Solar Century |
| Solar Fusion Ltd |
| SOLAR-ACTIVE |
| Solid Fuel Association |
| Solutions 4 Energy Ltd |
| Sony |
| Sony Television of Europe |
| South and West Yorkshire Energy Saving Trust advice centre |
| South Ayrshire Council |
| South East Carbon Action Network |
| South East Water |
| South Tyneside Homes |
| South West HECA Fora |
| Southampton City Council |
| Southern Landlords Association |
| Spelthorne Borough Council |
| Steel Window Association |
| Stockport Homes |
| Structherm Ltd |
| SummitSkills |
| Sustain Ltd |
| Sustainability 4 Yorkshire |