| Sapphire Buildings Limited | Real estate | 2021 |
| Saundersx Ltd | Wholesale & retail | 2025 |
| SAV Consultancy Ltd | Professional & scientific | 2023 |
| SBA Property Limited | Real estate | 2006 |
| SEB Property Development Ltd | Construction | 2020 |
| Sedbury Stores Limited | Real estate | 1973 |
| Selway Fisher Design Limited | Administrative & support | 2009 |
| Serendipity Care Homes Limited | Health & social care | 2011 |
| Serendipity Lane Ltd | Construction | 2025 |
| Seven Solutions Limited | Information & communication | 2002 |
| Seven Tournay Road Limited | Hospitality | 2002 |
| Severn and WYE Electrical Ltd | Construction | 2023 |
| Severn Federation Academy Trust | Education | 2020 |
| Severn Garage Door Services Ltd | Construction | 2021 |
| Severn Housing Collective Ltd | Real estate | 2021 |
| Severn Valley Group Ltd | Hospitality | 2022 |
| Severnside Properties Limited | Real estate | 2019 |
| Shire Access Ltd | Professional & scientific | 2021 |
| Shop@Theship Ltd | Wholesale & retail | 2019 |
| Shroom Renewables Limited | Administrative & support | 2022 |
| Shroom Tech Ltd | Administrative & support | 2022 |
| Shuttleworth Limited | Other services | 1997 |
| Sienna Aesthetics & Wellbeing Ltd | Other services | 2025 |
| Signs 4 YOU (UK) Limited | Manufacturing | 2009 |
| Simmie Ltd | Information & communication | 2023 |
| Sinderby Law Ltd | Extraterritorial | 2019 |
| Singularity Film Limited | Information & communication | 2018 |
| Sisu Skateboards Limited | Manufacturing | 2021 |
| Site Maintenance Services (South West) Limited | Construction | 2009 |
| SJC Autos Ltd | Wholesale & retail | 2020 |
| Skywheels Ltd | Manufacturing | 2021 |
| Sladegate Limited | Real estate | 1983 |
| Sm@Rt Clean Ltd | Administrative & support | 2017 |
| Small Strides CIC | Other services | 2014 |
| Smart Clean Services Ltd | Administrative & support | 2021 |
| Smart Ecology Ltd | Professional & scientific | 2017 |
| Smartspeccars Ltd | Professional & scientific | 2025 |
| SMF Engineering Limited | Manufacturing | 2010 |
| Smith & Underwood Scaffolding Ltd | Construction | 2023 |
| Smith L Limited | Wholesale & retail | 2024 |
| Smithfold Investments Ltd | Professional & scientific | 2014 |
| Smiths Funeral Services Limited | Other services | 2016 |
| SMN Transport Ltd | Transport & logistics | 2024 |
| Smoltech Ltd | Information & communication | 2012 |
| Snook Properties Ltd | Real estate | 2009 |
| Snowdrop 27 Ltd | Real estate | 2025 |
| Snowfern Ltd | Hospitality | 2023 |
| Somerton Construction Limited | Real estate | 2021 |
| Sonvcol Limited | Construction | 2023 |
| South Point Properties Limited | Households | 2025 |
| South West Sigma Limited | Professional & scientific | 2007 |
| Southwest Fork Lift Solutions Ltd | Manufacturing | 2018 |
| Southwest Tail Lift Services Limited | Transport & logistics | 2009 |
| SP Vehicle Services Ltd | Wholesale & retail | 2015 |
| Speedwedge (UK) Limited | Manufacturing | 2001 |
| Spence Airfield Associates Ltd | Arts & recreation | 2001 |
| Spindle Neurotech Limited | Manufacturing | 2026 |
| SPL Telecommunications Ltd | Information & communication | 2013 |
| Springfield Coleford Limited | Households | 1987 |
| SS and TS Properties Ltd | Real estate | 2026 |
| SST Investments Ltd | Real estate | 2021 |
| ST Briavels Meats Ltd | Manufacturing | 2019 |
| ST Pauls Street North Limited | Real estate | 2012 |
| ST. Briavels Lodge Management Company Limited | Households | 1982 |
| ST. John Investments Ltd | Real estate | 1998 |
| Stage Events Hire Ltd | Other services | 2025 |
| Staging Elite Limited | Arts & recreation | 2025 |
| Stand Films Limited | Professional & scientific | 2018 |
| Star Ventures Limited | Wholesale & retail | 2000 |
| Start 2 Finish Extensions and Renovations Ltd | Construction | 2012 |
| Station Court RTM Company Limited | Households | 2024 |
| Stay@Theship Ltd | Hospitality | 2019 |
| Stennar Ltd | Wholesale & retail | 2015 |
| Stennar Property Services Ltd | Households | 2015 |
| Stephen Duggan Transport Ltd | Transport & logistics | 2012 |
| Steve Matthews Travel Limited | Transport & logistics | 2007 |
| Straight Orbit Solutions Ltd. | Manufacturing | 2015 |
| Straw Spreader Ltd | Manufacturing | 2014 |
| Strawberry Rose Limited | Wholesale & retail | 2004 |
| Stretchevent Structures Ltd | Administrative & support | 2013 |
| Sturmey & Churchill Construction Limited | Construction | 2021 |
| STY Hmble Ltd | Manufacturing | 2025 |
| Sullivan Construction Ltd | Construction | 2026 |
| Sunkissed Tanning Studio (Lydney) Ltd | Other services | 2014 |
| Suspicious Minds Productions CIC | Administrative & support | 2024 |
| Swindon Heritage Trust | Education | 1990 |
| SWM (Insulations) Ltd | Wholesale & retail | 2011 |
| SWM Builders Merchants Chepstow Limited | Wholesale & retail | 2021 |
| SWM Holdings Limited | Financial services | 2023 |
| Sydenham House Care Home Ltd | Hospitality | 2013 |
| Symonds YAT Canoe Hire Limited | Administrative & support | 1996 |
| T J Contracting (UK) Limited | Construction | 2008 |
| T.J. Services (UK) Ltd | Construction | 2000 |
| Tack IT DAB IT Limited | Construction | 2025 |
| Tafft Limited | Administrative & support | 2016 |
| Talent Freight Ltd | Administrative & support | 2025 |
| Tamu Bros Ltd | Hospitality | 2018 |
| Tanhill Holdings Limited | Financial services | 2021 |
| TBP Property Holdings Ltd | Financial services | 2025 |
| TDC Commercial Bodyshops Ltd | Wholesale & retail | 2020 |