| Scheidt & Bachmann (UK) Limited | Manufacturing | 1999 |
| Scriveners Accountancy Ltd | Professional & scientific | 2010 |
| SD Smile Ltd | Health & social care | 2012 |
| SD Smile Properties Ltd | Real estate | 2018 |
| Sdcde Ltd | Hospitality | 2019 |
| Sears Soccer School LLP | | 2009 |
| Securesphere IT Ltd | Administrative & support | 2024 |
| Sedation Solutions (Clinical) LLP | | 2011 |
| Sedation Solutions Limited | Health & social care | 2010 |
| Sedgewall Limited | Information & communication | 2013 |
| Sega Amusements International Limited | Manufacturing | 1983 |
| Select Cleaning Ltd | Administrative & support | 2016 |
| Selfconstruction Ltd | Construction | 2015 |
| Sellyourhomeuk Ltd | Real estate | 2014 |
| Sensus Homes Limited | Construction | 2021 |
| Seoul Travel Co Limited | Administrative & support | 2002 |
| Serene Homecare Group Ltd | Health & social care | 2025 |
| Seven Market Ltd | Extraterritorial | 2024 |
| Seven Surbiton Hill Park Management Limited | Households | 1989 |
| Sevrion Ltd | Construction | 2026 |
| Shaman Ltd | Real estate | 2026 |
| Sharkish IT Ltd | Information & communication | 2023 |
| Sharpe ST James Limited | Administrative & support | 2013 |
| Sharpview Limited | Professional & scientific | 2018 |
| Shenlw Ltd | Real estate | 2019 |
| Shikra Cars Ltd | Wholesale & retail | 2022 |
| Shipperdoo Limited | Wholesale & retail | 2023 |
| Shoden Martial Arts Ltd | Education | 2024 |
| Shopxfinity Ltd | Wholesale & retail | 2026 |
| Shrewsbury Remapping Services Ltd | Wholesale & retail | 2023 |
| Sigurd Property Management Limited | Real estate | 2014 |
| Sijiasudio Ltd | Wholesale & retail | 2023 |
| Silky Cotton Limited | Transport & logistics | 2020 |
| Silver Hire Limited | Other services | 2025 |
| Simi Traders Limited | Wholesale & retail | 2025 |
| Simple Globe Ltd | Information & communication | 2022 |
| Simply Builders Ltd | Construction | 2024 |
| Simply EV (Surrey) Ltd | Construction | 2023 |
| Simply Fresh Supermarket Ltd | Wholesale & retail | 2016 |
| Simply LB Limited | Wholesale & retail | 2012 |
| Simply Snagging Ltd | Construction | 2022 |
| Simply the Club Limited | Arts & recreation | 2010 |
| Singh Flowers Ltd | Wholesale & retail | 2025 |
| Singz SA Trading Ltd | Wholesale & retail | 2023 |
| Siri Global Ltd | Real estate | 2021 |
| Siri Technologies Services Ltd | Information & communication | 2022 |
| SIX Fairfield West Limited | Households | 1995 |
| SJC Installation & Management Ltd | Construction | 2006 |
| SKG Resourcing Ltd | Information & communication | 2025 |
| Skin Warrior Ltd | Other services | 2021 |
| Skinhance Ltd | Health & social care | 2025 |
| SKM Real Estates Ltd | Professional & scientific | 2026 |
| Skopd Ltd | Information & communication | 2026 |
| Skydiamond Corporation Ltd | Professional & scientific | 2025 |
| Skydiamond Studios Ltd | Information & communication | 2025 |
| Skyline Investment Group Ltd | Real estate | 2015 |
| Slater and SON Limited | Construction | 2017 |
| Slcuk Ltd | Manufacturing | 2019 |
| Sles Property Ltd | Real estate | 2021 |
| Sloman Landscapes Ltd | Administrative & support | 2023 |
| SLS Hair and Beauty Ltd | Other services | 2025 |
| Small Power Consultancy Ltd | Professional & scientific | 2024 |
| Smart Maintenance+ Limited | Construction | 2014 |
| Smart Numbers London Limited | Professional & scientific | 2019 |
| Smartalec EDU Ltd | Education | 2016 |
| Smith and Ellis Construction Ltd | Construction | 2025 |
| Smkl Services Limited | Transport & logistics | 2018 |
| Snow White Food Ltd | Wholesale & retail | 2024 |
| SNS London Investments Limited | Real estate | 2024 |
| SO Demolition Ltd | Water & waste | 2019 |
| Softwareious Limited | Wholesale & retail | 2025 |
| Sokury Ltd. | Hospitality | 2013 |
| Solar Panels London Ltd | Manufacturing | 2023 |
| Sole Revival Limited | Wholesale & retail | 2023 |
| Solution Point Limited | Wholesale & retail | 1984 |
| Solution Technology Ltd. | Wholesale & retail | 1978 |
| Songster Management Company Limited | Households | 1988 |
| Sonrisa Ltd | Health & social care | 2026 |
| Sooriya Production Services Ltd | Information & communication | 2023 |
| SOS Professional Homecare Ltd | Health & social care | 2015 |
| Sothy Property Management LLP | | 2021 |
| Sound Bidco (UK) Limited | Financial services | 2026 |
| Sound Directions Limited | Wholesale & retail | 1998 |
| South Coast Trees Ltd | Agriculture & fishing | 2026 |
| South East & Surrey Homes Ltd | Construction | 2025 |
| Southern Roofing (South) Ltd | Construction | 2025 |
| Spades Real Estate Limited | Real estate | 2016 |
| Sparklin Limited | Wholesale & retail | 2025 |
| Specialist Redaction Service Limited | Administrative & support | 2025 |
| Spectrumforge Studios Ltd | Information & communication | 2025 |
| Spent Limited | Wholesale & retail | 2020 |
| Spets Security Ltd | Construction | 2023 |
| Spets Study Ltd | Other services | 2025 |
| Spring Building Solutions Ltd | Construction | 2014 |
| SR Health, Safety & Engineering Limited | Construction | 2009 |
| SRC Consulting Ltd | Professional & scientific | 2024 |
| Srgtec Ltd | Information & communication | 2016 |
| SRI Raghav IT Services Limited | Information & communication | 2005 |
| Ssambop Limited | Hospitality | 2016 |
| SSO Solutions Limited | Professional & scientific | 2023 |