| Sodiq Babawale Ltd | Health & social care | 2024 |
| SOE Services Ltd | Construction | 2024 |
| Sofi Halal Butcher & Grocery Ltd | Wholesale & retail | 2024 |
| Softbox Systems (TP3) Limited | Administrative & support | 2017 |
| Softbox Systems Holdings Limited | Professional & scientific | 2013 |
| Softbox Systems Limited | Manufacturing | 1995 |
| Softech Prime Solution Limited | Information & communication | 2022 |
| Softirq Solutions Ltd | Information & communication | 2017 |
| Softrixon Ltd | Information & communication | 2025 |
| SOL Projects Ltd | Construction | 2012 |
| Solace Property Ltd | Real estate | 2024 |
| Solaer UK Limited | Construction | 2013 |
| Solafields Limited | Construction | 2012 |
| Solar and Heating Co Ltd | Other services | 2022 |
| Solar Clear UK Limited | Administrative & support | 2016 |
| Solar Light SPV Ltd | Energy | 2014 |
| Solavento Electric Ltd | Manufacturing | 2026 |
| Solavento Ltd | Manufacturing | 2023 |
| Solestra Consulting Ltd | Professional & scientific | 2017 |
| Solis Enterprise Ltd | Real estate | 2021 |
| Solis Estate Ltd | Real estate | 2025 |
| Sollvera Ltd | Wholesale & retail | 2026 |
| Solo Active Ltd | Financial services | 2022 |
| Solucam Limited | Health & social care | 2011 |
| Solution OND Limited | Information & communication | 2019 |
| Solvecraft Ltd | Wholesale & retail | 2025 |
| Solvue Ltd | Financial services | 2019 |
| Something With Computers Limited | Professional & scientific | 2016 |
| Sonah Consultants Limited | Professional & scientific | 2017 |
| Sonite Limited | Administrative & support | 2017 |
| Sonix Studios Ltd | Manufacturing | 2025 |
| Sonnii Ltd | Professional & scientific | 2022 |
| Sonpsych Limited | Health & social care | 2025 |
| Sons of the Gobi Limited | Administrative & support | 2006 |
| Sorair Technologies Ltd | Information & communication | 2019 |
| Sorapura Limited | Manufacturing | 2014 |
| Sorinelys Ltd | Construction | 2021 |
| Sosa LDN Ltd | Wholesale & retail | 2020 |
| SOUCREDCENTRAL1 Ltd | Wholesale & retail | 2026 |
| Soul Health Solutions Limited | Health & social care | 2025 |
| Soul Space the Sisterhood Ltd | Education | 2021 |
| Soulbound Ltd | Professional & scientific | 2024 |
| Soultech Solutions Ltd | Information & communication | 2021 |
| Sound Alarm Systems Limited | Administrative & support | 2004 |
| Source 360 Ltd | Wholesale & retail | 2018 |
| South Africa Imports UK Ltd | Wholesale & retail | 2021 |
| South Asian Public Health Organisation (Sapho) Ltd | Health & social care | 2015 |
| South Central Building & Landscaping Ltd | Construction | 2013 |
| South Central Contractors Ltd | Construction | 2019 |
| South East Transport Training (UK) Ltd | Transport & logistics | 2015 |
| South East Windows and Doors Ltd | Construction | 2022 |
| South FIX Glazing Ltd. | Construction | 2012 |
| South Lodge Resources Limited | Professional & scientific | 2017 |
| South Street Barbers Ltd | Other services | 2016 |
| Sovereign Accountants (Bucks) Ltd | Professional & scientific | 2020 |
| Sovereign Private Risks Limited | Financial services | 2026 |
| Soyay Ltd | Construction | 2018 |
| SP 296 Limited | Hospitality | 2019 |
| SP Cloud Limited | Information & communication | 2010 |
| SP Engineering Consultancy Ltd | Professional & scientific | 2026 |
| Spa Education Academy Limited | Education | 2020 |
| Spacetime Systems Technology Ltd | Professional & scientific | 2025 |
| Spandrel Property Limited | Real estate | 2011 |
| Sparcs-It Solutions Limited | Information & communication | 2013 |
| Spark & Drive Ltd | Administrative & support | 2019 |
| Spark 21 | Education | 2015 |
| Sparkle and Shine Cleaning Services Aylesbury Limited | Administrative & support | 2026 |
| Sparks Marine Trimmers Ltd | Manufacturing | 2011 |
| Sparkx Group Limited | Construction | 2021 |
| Sparkx Limited | Construction | 2005 |
| Sparky Buddy Productions Limited | Arts & recreation | 2014 |
| Specialist IT Testing Solutions Limited | Information & communication | 2018 |
| Specialist Lending Ltd | Financial services | 2017 |
| Specialist Lending Management 1 Limited | Financial services | 2018 |
| Spectra London Ltd | Arts & recreation | 2024 |
| Spectrum Corporate Consultants Limited | Financial services | 2009 |
| Spectrum Electrical Solutions UK Limited | Construction | 2008 |
| Speedwell Physiotherapy Ltd | Health & social care | 2024 |
| Speedy Mortgages Ltd | Financial services | 2024 |
| Speedy NET (Buckinghamshire) Limited | Information & communication | 2010 |
| Speedy Plastics Ltd | Wholesale & retail | 2017 |
| Speedy Relocation Limited | Transport & logistics | 2017 |
| Speedy Rentals Vans Ltd | Administrative & support | 2025 |
| Speerhead Ventures Limited | Professional & scientific | 2019 |
| Spencer Lion Limited | Professional & scientific | 2004 |
| Spendwell Consulting Ltd | Professional & scientific | 2011 |
| Spice Garden Aylesbury Ltd | Hospitality | 2026 |
| Spike Enterprise Limited | Administrative & support | 2013 |
| Spirit Fit Limited | Wholesale & retail | 2010 |
| Spirit Irish Dance Limited | Arts & recreation | 2023 |
| SPK Consultancy Ltd | Professional & scientific | 2022 |
| SPK Training & Recruitment Limited | Education | 2015 |
| Splash Homes Ltd | Real estate | 2026 |
| Spoken Word Limited | Professional & scientific | 1992 |
| Spooner Construction Limited | Construction | 2024 |
| Sporting Integrity Limited | Administrative & support | 2009 |
| Sports Doctor London Limited | Extraterritorial | 2020 |
| Sports Medicine London Limited | Extraterritorial | 2020 |
| Sports Optimus Ltd | Professional & scientific | 2015 |
| Sportsmed Fitness Ltd | Health & social care | 2017 |