| SLY FOX Design Limited | Professional & scientific | 2018 |
| SM Shropshire Ltd | Real estate | 2024 |
| SM Woodhouse Ltd | Construction | 2020 |
| Small Animal Services Ltd | Professional & scientific | 2025 |
| Small City Homes Limited | Real estate | 2020 |
| Smart CUT Barber Ltd | Other services | 2024 |
| Smart Kitchen Utilities Ltd | Extraterritorial | 2016 |
| Smarter Build and Maintenance Limited | Construction | 2025 |
| Smarthooves Ltd | Wholesale & retail | 2017 |
| Smartway Holiday Property Management Ltd | Hospitality | 2025 |
| Smashlifeuk Ltd | Health & social care | 2018 |
| SMC Accountancy Services Limited | Professional & scientific | 2018 |
| SMC Custom Installations Limited | Wholesale & retail | 2006 |
| SMC Custom Installs Limited | Wholesale & retail | 2021 |
| SMC Operations Limited | Construction | 2008 |
| Smch Mortgages Ltd | Financial services | 2026 |
| SME Support Services Ltd | Administrative & support | 2018 |
| Smethurst Property Consultants Limited | Real estate | 2014 |
| SMG Property (Shifnal) Ltd | Construction | 2024 |
| SMG Property Group Limited | Financial services | 2024 |
| Smith & Jones Homes Ltd | Construction | 2020 |
| Smith + Ward Planning Ltd | Professional & scientific | 2022 |
| Smith and Milsom Ltd | Health & social care | 2018 |
| Smithers ERS Limited | Professional & scientific | 2012 |
| Smithers MDT Limited | Professional & scientific | 2020 |
| Smithers Quality Assessments Limited | Professional & scientific | 2010 |
| Smithers UK Holdings Limited | Professional & scientific | 2010 |
| SMJ Electrical Contractors Ltd | Other services | 2016 |
| SMJ Property Ltd | Real estate | 2017 |
| Smmc Holdings Ltd | Financial services | 2020 |
| Snagsure Homes Limited | Real estate | 2025 |
| Snagsure Limited | Professional & scientific | 2018 |
| Snailbeach Line Ltd. | Real estate | 2019 |
| Snipe Construction Ltd | Construction | 2023 |
| Snoop Shrewsbury Limited | Wholesale & retail | 2022 |
| Snowdon Grange Management Company Limited | Real estate | 2020 |
| Snowsports Instructor Academy Ltd | Arts & recreation | 2008 |
| Snowsure Services Ltd | Administrative & support | 2022 |
| SO Frank Ltd | Professional & scientific | 2024 |
| Soaring Soul Coaching Limited | Other services | 2024 |
| Social Heart C.I.C. | Administrative & support | 2015 |
| Social Telecoms C.I.C. | Information & communication | 2012 |
| Soden Collection - London Limited | Administrative & support | 2024 |
| Sofialex Trans Ltd | Transport & logistics | 2021 |
| Soft Flight Engineering Ltd | Information & communication | 2021 |
| Soja Property Limited | Real estate | 2025 |
| SOL EZE Limited | Wholesale & retail | 2022 |
| Solano International Limited | Transport & logistics | 2004 |
| Solano Rentals Ltd | Administrative & support | 2014 |
| Solar P V Battery Systems Ltd | Wholesale & retail | 2023 |
| Solid Gold Entertainment Limited | Arts & recreation | 2020 |
| Solmedia Holdings Limited | Financial services | 2024 |
| Solmedia Limited | Professional & scientific | 1934 |
| Solo Books Limited | Arts & recreation | 2000 |
| Solo Plumbing & GAS Ltd | Construction | 2026 |
| Solomon Company Holdings Ltd | Extraterritorial | 2020 |
| SOLVENCY2ACTUARIAL Ltd | Financial services | 2020 |
| Somerford Reach 2 Management Company Limited | Households | 2025 |
| Somerford Reach Management Company Limited | Households | 2021 |
| Sommerfield Road (Telford) Management Limited | Households | 2006 |
| Sonar Logistics Ltd | Professional & scientific | 2019 |
| Sonic Futures Ltd | Information & communication | 2019 |
| Sonic Games Limited | Manufacturing | 2009 |
| Sons & Roses Ltd | Wholesale & retail | 2018 |
| Sophia Court Management Company Limited | Real estate | 2007 |
| Sophie Copage Counselling Limited | Health & social care | 2023 |
| Sorbus Clinical Limited | Information & communication | 2026 |
| Sorrel Guesthouse Ltd | Hospitality | 2017 |
| Sorse Renewable Energies Limited | Construction | 2024 |
| SOS Agricultural Limited | Other services | 2008 |
| SOS Rental Limited | Real estate | 2024 |
| Soul Shropshire Ltd | Wholesale & retail | 2017 |
| Soulton Property Group Ltd | Real estate | 2025 |
| Sound Innovations Holdings Limited | Extraterritorial | 2020 |
| Sound Innovations Limited | Wholesale & retail | 2011 |
| Sound Innovations Retail Limited | Administrative & support | 2013 |
| Soundscape Studios Limited | Arts & recreation | 2003 |
| Source Design Holdings Ltd | Financial services | 2023 |
| Source Design Limited | Information & communication | 2007 |
| Sourcebynet UK Limited | Wholesale & retail | 2014 |
| Southall Maintenance Ltd | Water & waste | 2026 |
| Southdown Court (Polegate) Limited | Households | 1997 |
| Southill Solar Limited | Energy | 2016 |
| Souvea Ltd | Wholesale & retail | 2025 |
| Sovereign Building and Restoration Limited | Construction | 2012 |
| Sovereign Wealth Capital Limited | Real estate | 2017 |
| SP Education Solutions and Training Ltd | Education | 2025 |
| SP Property Management and Lettings Limited | Real estate | 2022 |
| SP Wilding Limited | Wholesale & retail | 2015 |
| Sp&D Group Ltd | Construction | 2024 |
| Spa Dental Properties LLP | | 2006 |
| Spacebase Coworking Limited | Real estate | 2026 |
| Spaces 2 BE Ltd | Construction | 2017 |
| Spad Investments Ltd | Financial services | 2018 |
| Spadental Limited | Health & social care | 2012 |
| Spadental Management LLP | | 2005 |
| Spadental Plymouth LLP | | 2006 |
| Spadental Ross on WYE LLP | | 2006 |
| Spadental South West Limited | Health & social care | 2017 |
| Spadental Whitchurch LLP | | 2014 |