| Sherborne Limited | Construction | 2001 |
| Sherborne of Farnborough Limited | Construction | 2021 |
| Sherborne of Windlesham Limited | Construction | 2021 |
| Sherborne Windows Ltd | Extraterritorial | 2005 |
| Sheridan Roofing and Home Services Ltd | Construction | 2025 |
| Sherpa Advisory Limited | Professional & scientific | 2025 |
| Sherwood Scientific Consulting Ltd | Professional & scientific | 2026 |
| Shire Furniture Ltd | Wholesale & retail | 2024 |
| Shirley Wellness Coaching Ltd | Other services | 2013 |
| Shirt Brigade Ltd | Wholesale & retail | 2021 |
| Shivrons Trading Ltd | Wholesale & retail | 2013 |
| Shoola Limited | Manufacturing | 2011 |
| Shopolera Ltd | Manufacturing | 2024 |
| Shore Road Garage Limited | Wholesale & retail | 1998 |
| Shore to Shore Ventures Limited | Wholesale & retail | 2021 |
| Shoreside Holdings Limited | Wholesale & retail | 2021 |
| Shoreside Homes Limited | Real estate | 2022 |
| Shout Telecoms Limited | Information & communication | 2001 |
| Shreducation Community Interest Company | Education | 2025 |
| SHS Garden Rooms Ltd | Construction | 2026 |
| SI Gardiner Ltd | Professional & scientific | 2024 |
| SIA UK Group Ltd | Financial services | 2019 |
| Sibling Supply Limited | Wholesale & retail | 2024 |
| Sidton Limited | Professional & scientific | 2022 |
| Sidwell Engineering Ltd | Administrative & support | 2016 |
| Sight Development Limited | Health & social care | 2003 |
| Signal Global Holdings Limited | Financial services | 2022 |
| Signal Global Limited | Other services | 2020 |
| Signature Decorating Ltd | Construction | 2024 |
| Signature Design Studio Ltd | Professional & scientific | 2026 |
| Silent Hours Limited | Information & communication | 2012 |
| Silkscreen Promotions Ltd | Manufacturing | 2025 |
| Sillence Marine Joinery Ltd | Manufacturing | 2017 |
| Silver Arch IL Limited | Construction | 2026 |
| Silver Arch Property Group Ltd | Construction | 2022 |
| Silver Shimmer Limited | Manufacturing | 2015 |
| Silvercross Limited | Other services | 2007 |
| Silverking Leisure Limited | Arts & recreation | 1995 |
| Silverstream Solar Limited | Construction | 2011 |
| Silvestris Limited | Information & communication | 2018 |
| Simantics Limited | Information & communication | 2008 |
| Simmcorp Ltd | Financial services | 2022 |
| Simmonds Kids Limited | Real estate | 2017 |
| Simple Accounts Ltd | Extraterritorial | 2020 |
| Simple Sailing Solutions Ltd | Education | 2013 |
| Simple Yachting Limited | Manufacturing | 2015 |
| Simply Balanced Solutions Ltd | Professional & scientific | 2017 |
| Simply Cake Toppers Ltd | Hospitality | 2015 |
| Simply Events Photos Ltd | Professional & scientific | 2016 |
| Simply Love Gardens Ltd | Administrative & support | 2023 |
| Simply Testing Ltd | Information & communication | 1995 |
| Simpson Recovery Limited | Administrative & support | 2022 |
| Since Properties Limited | Real estate | 2020 |
| SINCE13 Group Limited | Financial services | 2023 |
| Sindh Holdings Limited | Other services | 2023 |
| Singleton Cricket Club Limited | Arts & recreation | 2022 |
| Sinius Cube Consulting Limited | Professional & scientific | 2015 |
| Sirens Call Ltd | Information & communication | 2018 |
| Sirina Marine Ltd | Professional & scientific | 2021 |
| Site Build Limited | Administrative & support | 2012 |
| Site Event Limited | Administrative & support | 2014 |
| Site Safety Training Services Ltd | Construction | 2023 |
| Site-Equip Limited | Other services | 1995 |
| Sitech Engineering Ltd | Professional & scientific | 2025 |
| Sitejobs Ltd | Administrative & support | 2026 |
| Siwelcoaching Limited | Other services | 2024 |
| Sixteen Battersea Rise Residents Association Limited | Real estate | 2001 |
| Sixten & Cassey (Holdings) Limited | Wholesale & retail | 2011 |
| SJ Driving Group Limited | Transport & logistics | 2024 |
| SJ Group Solutions Ltd | Administrative & support | 2025 |
| SJ Power Limited | Construction | 2014 |
| SJD Production Ltd | Information & communication | 2021 |
| SJM Bookkeeping Ltd | Professional & scientific | 2025 |
| SJM Digital Services Limited | Other services | 2019 |
| Sjmqa Ltd | Administrative & support | 2026 |
| SJN Aesthetics Ltd | Other services | 2024 |
| SJP Services (Electrical) Limited | Construction | 2019 |
| SJS Maintenance and Repairs Limited | Construction | 2020 |
| SJT Communications Ltd | Information & communication | 2012 |
| SK Tanning Limited | Other services | 2024 |
| Skan Plumbing Heating Electrical Ltd | Construction | 2021 |
| Skapur Ltd | Other services | 2023 |
| SKC Freeholds Ltd | Real estate | 2023 |
| Skette Limited | Information & communication | 2020 |
| Skewer Limited | Manufacturing | 2003 |
| Skillpath Solutions Limited | Education | 2025 |
| Skin & Bones Homes Limited | Real estate | 2024 |
| Skin & Bones Limited | Health & social care | 2019 |
| Skin Canvas Ltd | Arts & recreation | 2025 |
| Skin Expert Clinic Limited | Other services | 2019 |
| Skin Forum Limited | Professional & scientific | 2010 |
| Skin With Melissa Limited | Other services | 2019 |
| Skincare Scientists Limited | Manufacturing | 2024 |
| Skinsister Limited | Other services | 2019 |
| Skizeen Limited | Real estate | 2010 |
| Sky High Lifting Ltd | Construction | 2017 |
| Sky M Limited | Wholesale & retail | 2024 |
| Sky Valley Records Ltd | Information & communication | 2025 |
| Sky Wardens Ltd | Administrative & support | 2026 |
| Skye Global Distribution Ltd | Transport & logistics | 2019 |