| Sensualis Limited | Wholesale & retail | 2024 |
| SENTIDO(1) Ltd | Real estate | 2024 |
| Sentinel Financial Planning Ltd | Financial services | 2019 |
| Sentinel Subfloor Solutions Ltd | Professional & scientific | 2026 |
| Serc Class Minibuses Ltd | Transport & logistics | 2025 |
| Seren Fach Childcare Limited | Education | 2000 |
| Serendib Retail Cardiff Limited | Wholesale & retail | 2025 |
| Serenity Homes Limited | Administrative & support | 2006 |
| Serennia Engineering and Design Ltd | Professional & scientific | 2024 |
| Sero Waste Ltd | Wholesale & retail | 2020 |
| Seroza Lock Limited | Real estate | 2017 |
| Serynni Limited | Professional & scientific | 2005 |
| Seshea Ltd | Health & social care | 2014 |
| Sessions News Limited | Households | 2018 |
| Sessions Properties Limited | Households | 2019 |
| Sevan Associates Limited | Professional & scientific | 2009 |
| Several Svcs UK Limited | Other services | 2018 |
| Severn GAS Transportation Limited | Professional & scientific | 2004 |
| Severn Office Solutions Ltd | Wholesale & retail | 2017 |
| Severn Power Limited | Energy | 2005 |
| Severn Steel Store Ltd | Wholesale & retail | 2026 |
| Severn Trading Holdings Limited | Real estate | 2025 |
| Severn Trading Limited | Construction | 2010 |
| Severn Valley IT Service Management Limited | Education | 2009 |
| Severnside Defibs and Training Ltd | Administrative & support | 2022 |
| Severnside Mortgage Solutions Ltd | Financial services | 2019 |
| Sevyn Vices Limited | Wholesale & retail | 2025 |
| Sewc Limited | Professional & scientific | 2016 |
| Sexstone Consulting Limited | Professional & scientific | 2012 |
| Señor Little's Ltd | Hospitality | 2025 |
| SF Accounts Limited | Professional & scientific | 2021 |
| SFA Development Ltd | Real estate | 2025 |
| SFD Consultancy Services Limited | Information & communication | 2016 |
| SFL Electrical Ltd | Construction | 2021 |
| SFM Blades Limited | Manufacturing | 2023 |
| SG & AI Limited | Professional & scientific | 2021 |
| SG Civils & Utilities Ltd | Construction | 2023 |
| SGC Geoconsult Ltd | Professional & scientific | 2025 |
| Sgiliau Cwmni BUD Cymunedaol CBC | Other services | 2018 |
| Sgiliau CYF | Education | 2016 |
| SGMSERVICES14 Limited | Construction | 2019 |
| SGR Performance Ltd | Wholesale & retail | 2017 |
| Sgta UK Ltd | Information & communication | 2010 |
| SH Expert Construction Ltd | Construction | 2021 |
| Shack'D UP Enterprises Ltd | Extraterritorial | 2018 |
| Shackleton FOX Developments Limited | Construction | 2023 |
| Shad Consultancy Limited | Professional & scientific | 2013 |
| Shad Properties Ltd | Real estate | 2024 |
| Shadi (NPT) Limited | Hospitality | 2012 |
| Shafayra E-Commerce Ltd | Wholesale & retail | 2026 |
| Shah Properties NP Ltd | Real estate | 2025 |
| Shahh Real Estate Ltd | Real estate | 2023 |
| Shahi Tandoori Ltd | Hospitality | 2018 |
| SHAKAR36 Ltd | Other services | 2026 |
| Shakti Massage and Healing Ltd | Other services | 2024 |
| Shalfleet Garage Ltd | Wholesale & retail | 2016 |
| Shameless Promotion Ltd | Arts & recreation | 2023 |
| Shampoodles IW Ltd | Other services | 2022 |
| Shams for Humanity CIC | Administrative & support | 2026 |
| Shamshamil Limited | Health & social care | 2018 |
| Shamsher Properties Ltd | Real estate | 2022 |
| Shanira PVT. Ltd | Construction | 2016 |
| Shanklin GAS Services Ltd | Construction | 2012 |
| Shanklin Manor Management Company Limited | Households | 2013 |
| Shanklin Towers Management Company Limited | Households | 1982 |
| Shapes Hair Limited | Other services | 2012 |
| Sharabash Ltd | Health & social care | 2025 |
| Sharland GAS Limited | Construction | 2024 |
| Sharmany Developments Limited | Construction | 2015 |
| Sharon Court (Cowes) Management Company Limited | Households | 1981 |
| Sharp-Shot Limited | Information & communication | 2012 |
| Shaun Mark Baldry Limited | Manufacturing | 2025 |
| Shauzel Capital Limited | Real estate | 2026 |
| Shaved Apple Limited | Construction | 2010 |
| Shaw Advisory Ltd | Professional & scientific | 2020 |
| Shaw Heating Services Ltd | Construction | 2020 |
| Shaw I.T. Consultancy Limited | Information & communication | 2012 |
| Shazel Properties Ltd | Real estate | 2025 |
| SHE Vibes Ltd | Other services | 2023 |
| Shearer Stortford Ltd | Health & social care | 2013 |
| Sheba Soul Ensemble C.I.C. | Arts & recreation | 2021 |
| Shedden Investments Limited | Financial services | 2012 |
| Sheds South Wales Limited | Construction | 2010 |
| Sheedy Demolition Limited | Wholesale & retail | 2004 |
| Shelfly.Co Limited | Administrative & support | 2025 |
| Shelton IT Consultancy Ltd | Information & communication | 2023 |
| Sheppard and SON Lifting Ltd | Construction | 2025 |
| Sheppards Fish Bar Limited | Hospitality | 2012 |
| Sheppy's Site Services Limited | Real estate | 2017 |
| Sherrington Limited | Extraterritorial | 2009 |
| Sherry Johnson Ltd | Health & social care | 2014 |
| Shervington Transport Ltd | Transport & logistics | 2019 |
| SHH Aestheticss Limited | Other services | 2025 |
| Shiby James Properties Limited | Real estate | 2018 |
| Shide Villa Management Company Limited | Households | 1990 |
| Shieldlab Limited | Construction | 2020 |
| Shift Electrical Limited | Construction | 2013 |
| Shift Music Events Limited | Arts & recreation | 2020 |
| Shilling IOW Limited | Construction | 2021 |
| Shillings Care Limited | Health & social care | 2020 |