| Softtech Systems Limited | Other services | 2019 |
| Software Clever Ltd | Information & communication | 2020 |
| Softwave Media Ltd | Information & communication | 2026 |
| Sogan Consulting Limited | Professional & scientific | 2013 |
| Sohal Fashions Ltd | Wholesale & retail | 2018 |
| Sohanpal Holdings Limited | Real estate | 2019 |
| Soho Care Ltd | Health & social care | 2024 |
| Soil Mixed Foundations Limited | Financial services | 2021 |
| Soixante Neuf Ltd | Wholesale & retail | 2012 |
| SOJ Consulting and Services Ltd | Information & communication | 2023 |
| Soke Enterprises Limited | Extraterritorial | 2005 |
| Sokleen Property Group Ltd | Administrative & support | 2025 |
| Soky Limited | Information & communication | 2017 |
| SOL Cipriani Ltd | Real estate | 2024 |
| Solace Pilates Events Ltd | Education | 2026 |
| Solace Pilates Holdings Ltd | Education | 2026 |
| Solace Pilates Ltd | Education | 2026 |
| Solace Pilates Wellbeing Ltd | Education | 2026 |
| Solace Place Care Limited | Health & social care | 2024 |
| Solaire Games Ltd | Information & communication | 2018 |
| Solandis Financial Concepts Ltd | Professional & scientific | 2024 |
| Solar Direction Limited | Real estate | 2024 |
| Solar Doctor Ltd | Construction | 2025 |
| Solar Immersion Ltd | Professional & scientific | 2016 |
| Solara Aesthetics Ltd | Other services | 2025 |
| Solent Knight Property Services Limited | Construction | 2025 |
| Solent PUB Company Limited | Hospitality | 2013 |
| Solera Solutions Ltd | Hospitality | 2026 |
| Solfar Property Solutions Ltd | Real estate | 2022 |
| Solid Base Scaffolding Ltd | Construction | 2026 |
| Solid Block Ecosse Limited | Financial services | 2020 |
| Solid Carbon Systems Limited | Manufacturing | 2025 |
| Solid Home Renovations Ltd | Construction | 2026 |
| Solid Rock Care Ltd | Administrative & support | 2023 |
| Solihull Superstars FC C.I.C. | Arts & recreation | 2019 |
| Solo (GM) Foot Care Ltd | Health & social care | 2010 |
| Solo Private Hire Limited | Transport & logistics | 2006 |
| Solo Travel Limited | Transport & logistics | 2024 |
| Solstice Architects Ltd | Administrative & support | 2017 |
| Solstice Impex Ltd | Wholesale & retail | 2026 |
| Solutex Fibre Ltd | Manufacturing | 2020 |
| Solutions NOW Limited | Information & communication | 2004 |
| Solutions-Un Limited | Construction | 2020 |
| Solve Applications Ltd | Information & communication | 2025 |
| Solvv Space Limited | Information & communication | 2024 |
| Somersult Limited | Wholesale & retail | 2013 |
| Somnoptima Limited | Health & social care | 2025 |
| Somtochukwu Ltd | Information & communication | 2026 |
| SON of SAM Limited | Information & communication | 2022 |
| Sonali VEG Ltd | Wholesale & retail | 2022 |
| Sondergrup Limited | Information & communication | 2025 |
| Sondhi & Co Ltd | Real estate | 2026 |
| Sonic Titan Records Ltd | Wholesale & retail | 2023 |
| Sonty Ltd | Transport & logistics | 2015 |
| SOO Organic Limited | Wholesale & retail | 2024 |
| Sooper Saver Ltd | Wholesale & retail | 2025 |
| Sooper Saver Store Ltd | Manufacturing | 2025 |
| Sooraj Consultancy Ltd | Information & communication | 2015 |
| Sophaq Ltd | Administrative & support | 2023 |
| Sophia a Price Limited | Health & social care | 2016 |
| Sophia and Zain Limited | Real estate | 2016 |
| Sophia Cosmetics Ltd | Wholesale & retail | 2020 |
| Sophisticated Catering Limited | Hospitality | 2025 |
| Sorella Property Investments Ltd | Real estate | 2024 |
| Sorhys Homes Limited | Real estate | 2025 |
| Sorin Independent Ltd | Transport & logistics | 2022 |
| Sorrell Properties Limited | Real estate | 2025 |
| Sorted and Solved Ltd | Administrative & support | 2026 |
| Sorted by Declutter Limited | Water & waste | 2026 |
| SOS Leak Detection & Prevention Limited | Construction | 2018 |
| SOS Topco Limited | Financial services | 2022 |
| SOS4 Ltd | Public administration | 2006 |
| Sosmathew Company Ltd | Health & social care | 2019 |
| Soul 2 Soul Kitchen Limited | Hospitality | 2021 |
| Soul Psychology Limited | Health & social care | 2021 |
| Soul Star Therapies Ltd | Arts & recreation | 2022 |
| Soule Croft Management Company Ltd | Households | 2024 |
| Soulful Co Limited | Education | 2025 |
| Soulightt Ltd | Professional & scientific | 2015 |
| Sound Approach Limited | Professional & scientific | 2004 |
| Soundrig Media Limited | Information & communication | 2024 |
| Souterrain Archaeological Services Limited | Professional & scientific | 1997 |
| South East Asian Trading Services Limited | Administrative & support | 2002 |
| South India Limited | Wholesale & retail | 2022 |
| South Plastering Ltd | Construction | 2016 |
| South Streams Offshore Resources UK Limited | Professional & scientific | 2024 |
| Southampton RIB Charter Ltd | Administrative & support | 2023 |
| Southams Auction Limited | Professional & scientific | 2017 |
| Southby Roofing Ltd | Construction | 2016 |
| Southern Acrylics Limited | Professional & scientific | 2018 |
| Southern Lasers & Surveying Equipment Limited | Professional & scientific | 2008 |
| Southern Park Homes Berkshire Ltd | Hospitality | 2020 |
| Southern Park Homes Ltd | Hospitality | 2024 |
| Southern Properties Berkshire Ltd | Real estate | 2020 |
| Southerncross Brewing Company Limited | Information & communication | 2016 |
| Southfreeze Refrigeration Ltd | Construction | 2025 |
| Southpaw Property Limited | Real estate | 2025 |
| Southways House (Management) Limited | Households | 1994 |
| Souv-Lucky House Ltd | Hospitality | 2025 |
| Sovereign House (Leighton Buzzard) RTM Company Limited | Households | 2024 |