| Sash Consulting Limited | Administrative & support | 2011 |
| Sasha Taylor Events & Consultancy Ltd | Hospitality | 2026 |
| Sassy N Trendy Cosmetics Ltd | Wholesale & retail | 2018 |
| SAT Trading Limited | Other services | 2001 |
| Satish Voralia SES Ltd | Professional & scientific | 2023 |
| Satkaar Ltd | Hospitality | 2025 |
| Satori Executive Search Limited | Administrative & support | 2015 |
| Sattech Consulting Limited | Information & communication | 2009 |
| Saturnia Holdings LP | | 2022 |
| Satvik Street Foods Limited | Wholesale & retail | 2025 |
| Saul Consulting Limited | Construction | 2017 |
| Saunders & Dolleymore LLP | | 2009 |
| Saurashtra Leuva Patel Samaj UK | Other services | 2015 |
| Sausan Beauty Ltd | Wholesale & retail | 2024 |
| Sauvereign UK Limited | Wholesale & retail | 2024 |
| SAV Auto Trade and Transport UK Limited | Wholesale & retail | 2022 |
| Savanna Management Ltd | Professional & scientific | 2022 |
| Savannah Estates Limited | Real estate | 2025 |
| Savar Ltd | Wholesale & retail | 2023 |
| Save Ukraine NOW Ltd | Wholesale & retail | 2022 |
| Save Your Energy Ltd | Construction | 2010 |
| Saveheights Limited | Wholesale & retail | 1994 |
| Savenest Limited | Wholesale & retail | 2026 |
| Savita's Jewels Ltd | Wholesale & retail | 2025 |
| Savoir Shop Limited | Wholesale & retail | 2024 |
| Savory Storiez Limited | Hospitality | 2025 |
| Savya Technology Limited | Information & communication | 2010 |
| Saxonpark Estates Limited | Hospitality | 2003 |
| SAY Svaha Ltd | Wholesale & retail | 2024 |
| Sayesbury Limited | Information & communication | 2014 |
| Sayesha Consulting Ltd | Information & communication | 2025 |
| SB & DB Limited | Real estate | 2024 |
| SB Building Group Ltd | Construction | 2025 |
| SB DE Vere Limited | Health & social care | 2016 |
| SB Enterprise Consultancy Limited | Professional & scientific | 2014 |
| SB Somore Limited | Hospitality | 2022 |
| SB Watford Ltd | Hospitality | 2025 |
| Sb&A Properties Limited | Real estate | 2025 |
| SBB Holding Ltd | Financial services | 2025 |
| SBH Projects Ltd | Wholesale & retail | 2025 |
| Sbibi Ltd | Wholesale & retail | 2025 |
| SBK House Ltd | Real estate | 2025 |
| Sbmk & Co Limited | Hospitality | 2016 |
| SBN Pro Trans Limited | Transport & logistics | 2019 |
| SBS Domus Limited | Real estate | 2016 |
| SBS Software Limited | Administrative & support | 2017 |
| SC Deps Ltd | Construction | 2024 |
| SC Networking UK Limited | Information & communication | 2010 |
| SC Somice Ltd | Transport & logistics | 2020 |
| SC Strategy Limited | Other services | 2012 |
| Scale Offline Ltd | Professional & scientific | 2025 |
| Scale Platforms Ltd | Information & communication | 2026 |
| Scan-Terieur Limited | Wholesale & retail | 1972 |
| Scanlon Family Company Limited | Professional & scientific | 2020 |
| Scanteya Ltd | Information & communication | 2017 |
| Scarbon Ltd | Information & communication | 2018 |
| Scarlet Developments Limited | Construction | 2008 |
| Scenery Corporation Ltd | Wholesale & retail | 2018 |
| Scentiria Limited | Wholesale & retail | 2025 |
| Schipor Joinery Fitting Services Ltd | Construction | 2022 |
| Schleich UK Limited | Wholesale & retail | 2005 |
| Schmart Global Trading Ltd | Wholesale & retail | 2022 |
| Schmooze Management Ltd | Real estate | 2018 |
| Schoenitz Dental Laboratory (UK) Limited | Health & social care | 1998 |
| Scholars Walk (Welwyn Garden City) Management Company Limited | Households | 2005 |
| Schs Properties Limited | Real estate | 2023 |
| Schuco Holdings Limited | Wholesale & retail | 2005 |
| Schuco International (London) Limited | Wholesale & retail | 1957 |
| SCI Regulatory Ltd | Professional & scientific | 2008 |
| Sciencenow Group Limited | Information & communication | 2006 |
| Scipture Portraits Limited | Arts & recreation | 2017 |
| Scissor Tables UK Ltd | Manufacturing | 2019 |
| SCJ Gilmartin Limited | Real estate | 2023 |
| SCJ Property Ltd | Real estate | 2021 |
| Scjr Consulting Limited | Information & communication | 2014 |
| SCL Nurseries Limited | Education | 2012 |
| Scma Group Ltd | Real estate | 2023 |
| Scoop & Smile Ltd | Hospitality | 2026 |
| Scorpio Properties Limited | Real estate | 2019 |
| Scotprop SPV Ltd | Real estate | 2022 |
| Scott Cole Management LLP | | 2023 |
| Scott Milburn Ltd | Professional & scientific | 2022 |
| Scout & Scale Ltd | Real estate | 2024 |
| SCR Building Ltd | Construction | 2016 |
| SCR Tech Limited | Information & communication | 2016 |
| Screenlaunch I.T. Limited | Information & communication | 1997 |
| Scrolly Limited | Information & communication | 2025 |
| Scrub a RUB DUB Launderette Ltd | Other services | 2024 |
| SCS Autos Ltd | Wholesale & retail | 2019 |
| SCS UK Holdings Limited | Financial services | 2024 |
| Scube Advisors Ltd | Professional & scientific | 2019 |
| Scurr Consulting Services Ltd | Information & communication | 2019 |
| SCW Commercial Services Ltd | Professional & scientific | 2023 |
| Scyberx Limited | Information & communication | 2019 |
| SD Accounting Services Limited | Administrative & support | 2023 |
| SD Boize & Co Ltd | Construction | 2019 |
| SD Health Ltd | Health & social care | 2018 |
| SD Lease Holdings Limited | Financial services | 2024 |
| SD Quartic Limited | Health & social care | 2024 |
| SD Residential Limited | Real estate | 2022 |