| Snowe Ltd | Health & social care | 2023 |
| Snowfed Consulting Ltd | Professional & scientific | 2023 |
| Snowy White Ltd | Health & social care | 2024 |
| SNR Land and Property Limited | Real estate | 2022 |
| Sntch Productions Ltd | Administrative & support | 2023 |
| SNV Construction Limited | Construction | 2015 |
| Snvm Technologies Ltd | Information & communication | 2018 |
| SO Financial Solutions Ltd | Administrative & support | 2026 |
| SO Orthopaedics Private Ltd | Health & social care | 2020 |
| SO Ward Limited | Administrative & support | 2013 |
| SOA Technology Ltd | Information & communication | 2013 |
| Soapstone Property Limited | Real estate | 2006 |
| Soar Engineering Ltd | Professional & scientific | 2023 |
| Socad Limited | Professional & scientific | 2023 |
| Socala Limited | Professional & scientific | 2012 |
| Soccerboot.Net Limited | Professional & scientific | 2003 |
| Sociabia Ltd | Wholesale & retail | 2022 |
| Social Care Solutions Limited | Health & social care | 2007 |
| Social Cell Limited | Professional & scientific | 2022 |
| Social Studio Cheshire Ltd | Professional & scientific | 2024 |
| Social Value Consultancy Limited | Administrative & support | 2018 |
| Social Value Quality Mark CIC | Administrative & support | 2019 |
| Socialcru Estates Ltd | Real estate | 2024 |
| Socialtap Holdings Ltd | Financial services | 2024 |
| Socialtap Ltd | Professional & scientific | 2019 |
| Societas Network Ltd | Administrative & support | 2024 |
| Societas Sales Ltd | Financial services | 2024 |
| Socius Accounting and Business Solutions Limited | Administrative & support | 2017 |
| Soeshe Engineering Ltd | Information & communication | 2006 |
| Soetrader Limited | Other services | 2009 |
| SOF Construction Ltd | Administrative & support | 2019 |
| Sofas & Rugs Limited | Wholesale & retail | 2023 |
| Sofi Express Ltd | Transport & logistics | 2023 |
| Sofia Construct Limited | Construction | 2026 |
| Soficm Limited | Real estate | 2018 |
| Sofology Limited | Wholesale & retail | 1983 |
| Softbrew Digital Limited | Information & communication | 2016 |
| Softico Limited | Information & communication | 2019 |
| Software Safety Solutions Limited | Professional & scientific | 2006 |
| Software Technologies Ltd | Information & communication | 2011 |
| Software-Upon-Thames Limited | Administrative & support | 2013 |
| Softwiz-It Limited | Information & communication | 2019 |
| Sohbhu Limited | Construction | 2017 |
| Soho Productions Limited | Information & communication | 2016 |
| Soibi Care Ltd | Health & social care | 2023 |
| Soibi Contracting Ltd | Wholesale & retail | 2025 |
| Soigne Events Ltd | Hospitality | 2025 |
| Sokama Limited | Professional & scientific | 2016 |
| Soko Advisory Ltd | Professional & scientific | 2022 |
| SOL Properties Ltd | Real estate | 2026 |
| SOL Training Ltd | Administrative & support | 2026 |
| Solan Productions Ltd | Information & communication | 2018 |
| Solan Properties Limited | Real estate | 2016 |
| Solan Sunbeds (Commercial) Limited | Other services | 2001 |
| Solan Tanning Ltd | Other services | 2024 |
| Solanda Ventures Limited | Professional & scientific | 2020 |
| Solar Progression UK Ltd | Construction | 2025 |
| Solar Teaching Ltd | Administrative & support | 2023 |
| Solaris Locum Ltd | Wholesale & retail | 2024 |
| Solarmax Limited | Professional & scientific | 2019 |
| Solas IT Services Limited | Information & communication | 2007 |
| Solas Medical Communications Ltd | Professional & scientific | 2026 |
| Soleil Rouge Ltd | Professional & scientific | 2025 |
| Soletanche Freyssinet IT UK Limited | Information & communication | 2003 |
| Solid Code Consultng Limited | Administrative & support | 2024 |
| Solid Fuel Supplies Ltd | Extraterritorial | 2015 |
| Solid Fuels Ltd | Extraterritorial | 2015 |
| Solid Solutions Consulting Limited | Information & communication | 2017 |
| Solid Structures North West Limited | Construction | 2023 |
| Solidcad Limited | Other services | 2006 |
| Solidworkers Ltd | Professional & scientific | 2019 |
| Solightify Ltd | Wholesale & retail | 2024 |
| Solirex Ltd | Information & communication | 2016 |
| Solmet Systems Ltd | Manufacturing | 2026 |
| Solomon Properties Limited | Real estate | 2022 |
| Solomons Pharmacy Limited | Wholesale & retail | 2023 |
| Solsave Ltd | Wholesale & retail | 2008 |
| Solstice 25 Limited | Administrative & support | 2025 |
| Soluchan Limited | Administrative & support | 2024 |
| Solucium Consulting Limited | Information & communication | 2017 |
| Solution Talk LLP | | 2016 |
| Solutioneers Limited | Information & communication | 2007 |
| Solutions 2 Enterprise Ltd | Information & communication | 2001 |
| Solutions Construction Holdings Limited | Financial services | 2024 |
| Solutions Construction Personnel Group Limited | Administrative & support | 2024 |
| Solutions Construction Personnel Limited | Administrative & support | 2017 |
| Solvability Limited | Professional & scientific | 2019 |
| Solvay Interox Limited | Wholesale & retail | 1971 |
| Solvay UK Holding Company Limited | Financial services | 1992 |
| Solve Structural Design Ltd | Professional & scientific | 2005 |
| Solvexis Consulting Limited | Administrative & support | 2014 |
| Some More Ltd | Wholesale & retail | 2024 |
| Somerset SC Ltd | Administrative & support | 2024 |
| Somewatch Limited | Professional & scientific | 1932 |
| Somewin Limited | Professional & scientific | 1976 |
| SON of BOB Limited | Wholesale & retail | 2010 |
| Sona Cinema Limited | Professional & scientific | 2024 |
| Sona Projects Limited | Professional & scientific | 2012 |
| Sona Property Media Limited | Professional & scientific | 2025 |
| Sonar Unlimited Holdings Limited | Financial services | 2024 |