| Solosmiles Ltd | Information & communication | 2021 |
| Solution Dotcom Ltd | Professional & scientific | 2013 |
| SOLUTION2SUCCESS Limited | Education | 2024 |
| Solvent Advertising Ltd | Professional & scientific | 2022 |
| Solventa Ltd | Administrative & support | 2026 |
| Solytics Partners UK Limited | Information & communication | 2023 |
| SOM TUM Thai Limited | Hospitality | 2016 |
| Somas Optics Limited | Health & social care | 2016 |
| Someplace Ltd | Hospitality | 2024 |
| Somerville Bain Associates Limited | Administrative & support | 1992 |
| Something Else PVT Ltd | Wholesale & retail | 2014 |
| Somniferum Ltd | Health & social care | 2019 |
| Somoni Limited | Information & communication | 2004 |
| SON Adhavan Ltd | Wholesale & retail | 2019 |
| Sonali Parekh Enterprises Ltd | Other services | 2020 |
| Sonas Management Ltd | Administrative & support | 2018 |
| Sonatarun’S Kitchen Limited | Hospitality | 2022 |
| Soni Tools Private Limited | Wholesale & retail | 2011 |
| Sonkarr Imports & Exports Limited | Professional & scientific | 1996 |
| Sonorous Consulting Limited | Professional & scientific | 2019 |
| Sougtani Limited | Hospitality | 2016 |
| Soul Properties Ltd | Real estate | 2017 |
| Soule Limited | Information & communication | 2024 |
| Sound Web Marketing Limited | Extraterritorial | 2015 |
| Soundz Good Limited | Professional & scientific | 2008 |
| Southern Bridging Ltd | Financial services | 2010 |
| Southgate Estates Limited | Real estate | 2019 |
| Sovereign Cleaning and Maintenance Limited | Other services | 2022 |
| Spa Healthcare (UK) Limited | Wholesale & retail | 2006 |
| Spaceage Properties Ltd | Real estate | 2012 |
| Spacedmonkey Limited | Information & communication | 2017 |
| Spacelinx Ltd | Information & communication | 2012 |
| Spacemaker Furniture Limited | Wholesale & retail | 1998 |
| Spacemaker Group Limited | Wholesale & retail | 1997 |
| Spark Financial Consultancy Limited | Professional & scientific | 2015 |
| Spark Paradise Properties Limited | Real estate | 2017 |
| Spark Projects Consultancy Limited | Professional & scientific | 2019 |
| Sparkk Ltd | Wholesale & retail | 2014 |
| Sparrow Lettings Limited | Real estate | 2024 |
| Sparrow Management Limited | Real estate | 2017 |
| SPB Financial Consultancy Ltd | Administrative & support | 2019 |
| Spb-Sa Holding Co Limited | Financial services | 2024 |
| SPD Motors & Suppliers Ltd | Wholesale & retail | 2017 |
| Special Projects and Research Ltd | Wholesale & retail | 2014 |
| Spectrum Reward Solutions Ltd | Professional & scientific | 2024 |
| Speed 9395 Limited | Real estate | 2002 |
| Speedy Home Care Ltd | Health & social care | 2025 |
| Spelbridge Limited | Real estate | 2022 |
| Spgl Limited | Administrative & support | 2008 |
| Spice Guru Ltd | Hospitality | 2024 |
| Spinefix Limited | Health & social care | 2024 |
| Spinview Limited | Information & communication | 2016 |
| Spinview Partners 2 Limited | Professional & scientific | 2026 |
| Spinview Partners Limited | Professional & scientific | 2026 |
| Spiros Motor Technicians Limited | Wholesale & retail | 2011 |
| SPN Medical Services Ltd | Health & social care | 2018 |
| Sporting 4 Schools Limited | Professional & scientific | 2012 |
| Sports Hospitality Ltd | Arts & recreation | 2009 |
| Sports Impact Partners Ltd | Professional & scientific | 2023 |
| Sports Port Limited | Professional & scientific | 2004 |
| SPP Services Ltd | Information & communication | 2024 |
| Sprashanth Ltd | Real estate | 2022 |
| Sprat's Plaice Limited | Wholesale & retail | 2009 |
| Springsphere Holdings Limited | Financial services | 2024 |
| Springwell Farm Limited | Agriculture & fishing | 2000 |
| Sprout Behaviour Change Limited | Health & social care | 2017 |
| Sprout Health Solutions Limited | Health & social care | 2020 |
| Spud N Scoop Ltd | Hospitality | 2025 |
| SPV (Woodhouse Road) Limited | Real estate | 2008 |
| Spyk Limited | Real estate | 2018 |
| Squareshot Limited | | 1986 |
| SR Innovation Limited | Professional & scientific | 2018 |
| SR Project Consultants Ltd | Professional & scientific | 2023 |
| SRD Global Investments Ltd | Information & communication | 2025 |
| SRI Business Centre Ltd | Real estate | 2024 |
| SRI Estate Agent Limited | Professional & scientific | 2024 |
| Srimati Boutique Limited | Wholesale & retail | 2024 |
| Srinithya Group Limited | Real estate | 2017 |
| Srkm Properties Limited | Real estate | 2021 |
| SRMETRIC24 Ltd | Professional & scientific | 2024 |
| SS Building & Repairs Ltd | Construction | 2020 |
| SS Cloud Solutions Limited | Information & communication | 2016 |
| SS Global Ltd | Other services | 2013 |
| Ssaa Consulting Ltd | Information & communication | 2024 |
| Ssbj Investments Limited | Real estate | 2017 |
| SSCCO2T Tech Limited | Information & communication | 2021 |
| Ssgdeurope Ltd | Education | 2026 |
| SSK 39 Builders Limited | Construction | 2024 |
| SSK SPV Ltd | Real estate | 2021 |
| Ssma Ltd | Real estate | 2016 |
| Sspc Solutions Ltd | Real estate | 2014 |
| SSR Consultancy Limited | Professional & scientific | 2015 |
| SSR Investment Group Limited | Real estate | 2018 |
| SSS Retail Ltd | Wholesale & retail | 2023 |
| Ssyv Holdings Limited | Real estate | 2022 |
| ST Dennis Pharma Limited | Real estate | 2021 |
| ST John's School, Northwood | Education | 1997 |
| ST Johns Housing CIC | Households | 2026 |
| ST Neots Convenience Limited | Wholesale & retail | 2016 |
| ST Stephen Punjab Limited | Real estate | 2021 |