| Skylark Luggage Ltd | Wholesale & retail | 2023 |
| Skyline Private Ltd | Real estate | 2020 |
| SL Biopharma Consultants Ltd | Professional & scientific | 2023 |
| Sl.A Services Ltd | Professional & scientific | 2017 |
| Slam Marketing Ltd | Professional & scientific | 2014 |
| Slavic Empire Ltd | Construction | 2024 |
| SLB Hospitality Ltd | Hospitality | 2022 |
| Slcr Holdings Limited | Financial services | 2020 |
| Sleek Salon Ltd | Other services | 2025 |
| Slick Panels Ltd | Wholesale & retail | 2019 |
| Sloikiteam Ltd | Wholesale & retail | 2026 |
| SLS Vacation Stay Limited | Hospitality | 2023 |
| Slvariation Ltd | Wholesale & retail | 2025 |
| SM Bains Properties Limited | Real estate | 2021 |
| SM Building Services Ltd | Construction | 2022 |
| SM Recovery Kent Ltd | Transport & logistics | 2021 |
| Small BUT Mighty Community CIC | Other services | 2025 |
| Smark Consultancy Ltd | Professional & scientific | 2024 |
| Smart CI Group Ltd | Professional & scientific | 2010 |
| Smart Civil Engineering Ltd | Other services | 2017 |
| Smart Glow Ltd | Construction | 2022 |
| Smart Hair Ltd | Other services | 2014 |
| Smart Hire U.K. Ltd | Administrative & support | 2023 |
| Smart Home Renovations Limited | Construction | 2018 |
| Smart Mael Limited | Real estate | 2025 |
| Smart Mechanical Services Limited | Construction | 2018 |
| Smart P.R. Limited | Professional & scientific | 2019 |
| Smart Pecunia Limited | Real estate | 2005 |
| Smart Review Pensions Limited | Other services | 2019 |
| Smart Team Maintenance Limited | Manufacturing | 2011 |
| Smart Testing Ltd | Professional & scientific | 2024 |
| Smart Ventilation Solutions Limited | Construction | 2018 |
| Smartdeko Ltd | Construction | 2024 |
| Smash the Stigma C.I.C. | Arts & recreation | 2025 |
| Smats Services Ltd | Professional & scientific | 2004 |
| Smav Property Management Services Limited | Real estate | 2017 |
| Smaz Medical Ltd | Health & social care | 2026 |
| SMB Building Contracts Limited | Construction | 2017 |
| SME Mechanical Services Limited | Construction | 2017 |
| SMH Heating & Plumbing Works Limited | Construction | 2015 |
| Smith's Properties Investments Ltd | Real estate | 2023 |
| SMS Surfacing Ltd | Construction | 2019 |
| Smtk Ltd | Transport & logistics | 2024 |
| SMW Cooling Ltd | Construction | 2022 |
| SN Bidco Limited | Hospitality | 2016 |
| SN Holdco Limited | Hospitality | 2016 |
| Snap Fit IT Solutions Ltd | Information & communication | 2022 |
| SND Haulage Ltd | Transport & logistics | 2026 |
| SNJ Solutions Limited | Information & communication | 2013 |
| Snodland Development Limited | Real estate | 2000 |
| Snug Dubs Camper Hire Limited | Administrative & support | 2023 |
| Sofia G Consulting Ltd | Professional & scientific | 2023 |
| Softforge Limited | Information & communication | 2008 |
| Softplay Bounce Ltd | Arts & recreation | 2024 |
| Sohan Design Ltd | Professional & scientific | 2023 |
| Sohi Express Ltd | Transport & logistics | 2026 |
| Soimak Ltd | Other services | 2011 |
| SOJ Cargo Service Limited | Transport & logistics | 2024 |
| Soji Marketing Limited | Professional & scientific | 2024 |
| Solar Collective Holdings Ltd | Other services | 2025 |
| Solar Collective Ltd | Professional & scientific | 2017 |
| Solar Integrated Services Ltd | Construction | 2024 |
| Solar Panna Ltd | Wholesale & retail | 2026 |
| Solar Property Ltd | Households | 2025 |
| Soldi Partners Ltd | Professional & scientific | 2019 |
| Solid Premier Construction Ltd | Construction | 2025 |
| Solo Heating Installations Limited | Construction | 2008 |
| Solo Tour With David Co. Ltd | Administrative & support | 2025 |
| Solomon's Estate Ltd | Real estate | 2024 |
| SOLOTRUCK25 Ltd | Transport & logistics | 2025 |
| Solus Beverage Solutions Ltd | Manufacturing | 2022 |
| Solus Group Ltd | Financial services | 2022 |
| Solution Embassy Housing Limited | Hospitality | 2020 |
| Solutions by Trio Ltd | Administrative & support | 2017 |
| Solutions for Brave Logistics Transport Ltd | Transport & logistics | 2026 |
| Solutions of Candour Ltd | Professional & scientific | 2018 |
| Somnium House Ltd | Real estate | 2025 |
| Sonair Properties Ltd | Real estate | 2019 |
| Sonia Auto Car Care Ltd | Wholesale & retail | 2024 |
| Sonia Mathews Locum Ltd | Health & social care | 2021 |
| Sophie Kane Events Ltd | Administrative & support | 2025 |
| Sora Sync Ltd | Information & communication | 2025 |
| Soreyan Limited | Health & social care | 2020 |
| Sosah Ltd | Construction | 2023 |
| SOT Consult Limited | Professional & scientific | 2026 |
| Soteria Healthcare Services Ltd | Health & social care | 2023 |
| Soule Services Limited | Professional & scientific | 2025 |
| Source Secured Limited | Real estate | 2019 |
| Sourcedforyou Ltd | Wholesale & retail | 2024 |
| South Barracks Management Company Limited | Households | 1998 |
| South East Bathroom Co Ltd | Construction | 2026 |
| South East Drylining Contractors Ltd | Construction | 2012 |
| South East London Crane Hire Limited | Administrative & support | 2019 |
| South East Surveying Ltd | Professional & scientific | 2023 |
| South East Wineries Limited | Manufacturing | 2017 |
| South Eastern Maintenance Services Ltd | Manufacturing | 2023 |
| South Essex Auctions Ltd | Wholesale & retail | 2025 |
| South London Critical Care Limited | Health & social care | 2015 |
| South London Music Centre Limited | Education | 2025 |
| Southall Close Management Limited | Households | 2019 |