| Stress Concern International Ltd | Health & social care | 2006 |
| Strideon Limited | Administrative & support | 2011 |
| Strive Motors Limited | Wholesale & retail | 2023 |
| Strong-Gens C.I.C. | Health & social care | 2018 |
| Strongvox (Leasing) Limited | Real estate | 2006 |
| Strongvox Homes Limited | Real estate | 2009 |
| Strongvox Limited | Construction | 2003 |
| Stu&Jools Pizzeria Ltd | Hospitality | 2026 |
| Stuart Garden Architecture Limited | Manufacturing | 1988 |
| Stubbygrove Properties Limited | Construction | 2015 |
| Studio Brio Ltd | Information & communication | 2023 |
| Studio Diva Ltd | Extraterritorial | 2018 |
| Studio Faber Ltd | Professional & scientific | 2023 |
| Studio Milla Ltd | Professional & scientific | 2019 |
| Studio Mitchell Limited | Professional & scientific | 2013 |
| Study Stamina Limited | Manufacturing | 2022 |
| Stuff to DO Today Limited | Information & communication | 2014 |
| Stump Solutions Limited | Agriculture & fishing | 2011 |
| Style Hotels Limited | Hospitality | 2003 |
| Suave Investments Limited | Professional & scientific | 2009 |
| Subterrain Ltd | Professional & scientific | 2022 |
| Sudhakaran Ltd | Health & social care | 2014 |
| Suffolk Court Management (Taunton) Limited | Households | 1970 |
| Summerfield Commercial Property Ltd | Construction | 2006 |
| Summerfield Court (Taunton) Residents Management Company Limited | Households | 1977 |
| Summerfield Developments Limited | Real estate | 1987 |
| Summerfield Estates Ltd | Construction | 1993 |
| Summerfield Properties Ltd | Real estate | 1990 |
| Summerfield SD3 (Homes) Limited | Real estate | 2006 |
| Summerlands Court Management Company Limited | Households | 1974 |
| Summitdown LP | | 2012 |
| Sun Safe Playsystems Limited | Construction | 1999 |
| Sun Scaffolding Limited | Construction | 2002 |
| Suncraft Solar Ltd | Professional & scientific | 2011 |
| Sunovis Ltd | Financial services | 2012 |
| Sunrise Farm Properties Ltd | Real estate | 2026 |
| Sunrise Nederland Holding Ltd | Extraterritorial | 2011 |
| Sunrise Nederland Ltd | Real estate | 2011 |
| Sunshine Conversions Ltd | Wholesale & retail | 2026 |
| Sunshine Official Ltd | Wholesale & retail | 2025 |
| Supernovaseven Limited | Administrative & support | 2012 |
| Superpro Europe Limited | Wholesale & retail | 2020 |
| Superstar Training Club MID Devon Ltd | Arts & recreation | 2026 |
| Supply Chain Support Limited | Administrative & support | 2025 |
| Supreme Engineering UK Limited | Manufacturing | 2003 |
| Surbiton Medical Ltd | Health & social care | 2023 |
| Sure Scaff Scaffolding Ltd | Construction | 2019 |
| Sureroute Secure Ltd | Health & social care | 2025 |
| Surfing COW Group Limited | Manufacturing | 2019 |
| Surma (Yeovil) Limited | Hospitality | 2012 |
| Survey Engineering Solutions Limited | Mining & quarrying | 2015 |
| Survey Standards Ltd | Professional & scientific | 2008 |
| Sussex Equine Properties Holdings Limited | Financial services | 2021 |
| Sussex Equine Properties Limited | Real estate | 2021 |
| Sussex Rural Contracting Services Ltd | Administrative & support | 2023 |
| Sustainable Drainage Systems Limited | Manufacturing | 2002 |
| Sutton Lucy Dairy Ltd | Manufacturing | 2017 |
| Svengali Operations Limited | Arts & recreation | 2002 |
| SVG Medical Solutions Ltd | Health & social care | 2019 |
| SVG Services Limited | Professional & scientific | 2007 |
| SVP Project Services Limited | Construction | 2024 |
| SW Education & Care Ltd | Health & social care | 2019 |
| SW Healthcare Holdings Limited | Financial services | 2024 |
| SW Healthcare Partnership Limited | Health & social care | 2005 |
| Swallow Court Devon Ltd | Real estate | 2023 |
| Swallow Point Limited | Hospitality | 2011 |
| Swan Advocacy Network | Health & social care | 2008 |
| Swan at Kingston ST Mary Ltd | Hospitality | 2026 |
| Swan GP Ltd | Health & social care | 2025 |
| Swan Health and Wellbeing Ltd | Wholesale & retail | 2020 |
| Swan Training Services Ltd | Health & social care | 2016 |
| Swanmore Estates Limited | Construction | 1987 |
| Swapna Ltd | Health & social care | 2009 |
| Swec Property Ltd | Real estate | 2019 |
| Sweet Surprise (South West) Limited | Education | 2016 |
| Sweet Surprise Somerset Limited | Extraterritorial | 2025 |
| Sweet Victory Products Limited | Wholesale & retail | 2016 |
| Sweethay Developments Limited | Hospitality | 2010 |
| Sweethay Glamping Holidays Ltd | Hospitality | 2023 |
| Sweethay Meadow Glamping Ltd | Hospitality | 2023 |
| Sweetland Autos Ltd | Professional & scientific | 2026 |
| Sweets for Life Somerset Ltd | Wholesale & retail | 2012 |
| Swflooringuk Ltd | Construction | 2021 |
| Swhospitalitysolutions Ltd | Hospitality | 2026 |
| Swift Services (SW) Ltd | Professional & scientific | 2024 |
| Swoopco Ltd | Wholesale & retail | 2020 |
| SWP Strategies Ltd | Professional & scientific | 2026 |
| Swwisp Limited | Information & communication | 2011 |
| Swwm Ltd | Transport & logistics | 2013 |
| Sycamore ROW (North Curry) Limited | Professional & scientific | 2011 |
| Symbiosis Delta Limited | Information & communication | 1998 |
| Symco Industrial Supplies Limited | Extraterritorial | 2010 |
| Syme Healthcare Ltd | Health & social care | 2013 |
| Symes Assets Limited | Financial services | 2025 |
| Symetrics Ltd | Information & communication | 2004 |
| Symtegra Ltd | Professional & scientific | 2014 |
| Synchiq Limited | Information & communication | 2024 |
| Synergy Nest Ltd | Real estate | 2026 |
| Synergy Solutions Software Limited | Extraterritorial | 2016 |
| Synogix UK Limited | Wholesale & retail | 2009 |