| Skin&Spirit Limited | Health & social care | 2022 |
| SKS Building Developments Ltd | Construction | 2023 |
| SKX Aesthetics Limited | Health & social care | 2020 |
| Sky EYE Surveys Ltd | Professional & scientific | 2020 |
| Sky Retail Limited | Wholesale & retail | 2018 |
| Skyfall Property Holdings Limited | Real estate | 2017 |
| Skyline Supplies Ltd | Wholesale & retail | 2001 |
| SL Coupe Holdings Limited | Financial services | 2025 |
| SL Safeguarding Services Ltd | Health & social care | 2024 |
| Slaa Properties Ltd | Households | 2022 |
| Slater's Snug Ltd | Hospitality | 2021 |
| Slight Engineer Ltd | Other services | 2025 |
| Slim Systems Limited | Manufacturing | 2010 |
| Slittingmill Holdings Ltd | Financial services | 2025 |
| Sloegasm Limited | Manufacturing | 2009 |
| Slooks Limited | Information & communication | 2007 |
| Sloungies Limited | Wholesale & retail | 2019 |
| Slowmo Group Limited | Financial services | 2026 |
| SLR Mortgage Services Limited | Financial services | 2020 |
| SLS Logistics Ltd | Transport & logistics | 2020 |
| Small Acorn Investments Ltd | Real estate | 2024 |
| Small Business Accountants Limited | Professional & scientific | 2000 |
| Smart Acquisition Group Ltd | Real estate | 2023 |
| Smart Business Finance Limited | Financial services | 2019 |
| Smart Cleaners & Housekeepers Ltd | Real estate | 2018 |
| Smart Corporate Lets Limited | Real estate | 2018 |
| Smart Corporate Stays Limited | Professional & scientific | 2020 |
| Smart Energy Efficient Solutions Ltd | Wholesale & retail | 2023 |
| Smart Follow Strategy Limited | Financial services | 2025 |
| Smart Habit Limited | Professional & scientific | 2022 |
| Smart Heat Experts Limited | Construction | 2025 |
| Smart Menswear Ltd | Wholesale & retail | 2025 |
| Smart Paving & Groundwork (UK) Ltd | Construction | 2010 |
| Smart Properties Solutions Limited | Real estate | 2013 |
| Smart Property Investors Academy Limited | Education | 2018 |
| Smart Serviced Lets Ltd | Real estate | 2017 |
| Smart Step Learning Ltd | Education | 2022 |
| Smart Thinking Business Solutions Limited | Hospitality | 2017 |
| Smart Work Stays Ltd | Hospitality | 2023 |
| Smartbuild North Ltd | Construction | 2025 |
| SMC Business Management Support Services Limited | Administrative & support | 2021 |
| SMD Van & Plant Hire Limited | Administrative & support | 2021 |
| SME Commercial Finance Limited | Administrative & support | 2023 |
| SME Commercial Funding Limited | Extraterritorial | 2023 |
| SME Commercial Holdings Limited | Extraterritorial | 2023 |
| SME Commercial Lending Limited | Extraterritorial | 2023 |
| SME Management Limited | Administrative & support | 2017 |
| Smeckley Wood Ltd | Real estate | 2024 |
| SMG Global Holdings Limited | Financial services | 2025 |
| Smile by Design (Sheffield) Limited | Health & social care | 2024 |
| Smile by Design Limited | Health & social care | 2005 |
| Smith Elite Metals Limited | Water & waste | 2007 |
| Smith Home Improvement Services Ltd | Construction | 2020 |
| Smith ZJ Ltd | Health & social care | 2023 |
| Smithfield Lofts Properties Limited | Real estate | 2023 |
| Smiths Engineering Ltd. | Professional & scientific | 2011 |
| Smiths Property SERV1CES Limited | Transport & logistics | 2026 |
| SMK Chesterfield Limited | Wholesale & retail | 2015 |
| Smmc Limited | Professional & scientific | 2016 |
| SMP Building Products Ltd | Manufacturing | 2022 |
| SMS Group Technical Services (UK) Limited | Manufacturing | 2008 |
| Smtp Server Specialist Ltd | Information & communication | 2011 |
| Smylie LYE Properties Limited | Real estate | 2021 |
| SN Living Ltd | Hospitality | 2026 |
| SNB PVT Limited | Hospitality | 2017 |
| Snfrl Limited | Financial services | 2022 |
| SNG Private Ltd | Hospitality | 2024 |
| Snoop and Choop Ltd | Real estate | 2024 |
| Snorscomb Technology Limited | Real estate | 2006 |
| Snow ELK Productions Ltd | Information & communication | 2011 |
| Snow Pony Limited | Wholesale & retail | 2011 |
| Snowcroft UK Limited | Hospitality | 2002 |
| Snowline Housewares Limited | Extraterritorial | 1990 |
| Snugbums Limited | Wholesale & retail | 2020 |
| SOB Properties Limited | Real estate | 2021 |
| Sobti and Sobti Ltd | Real estate | 2018 |
| Sobti Finances and Investments Limited | Hospitality | 2010 |
| Social One Bars Limited | Hospitality | 2020 |
| Social Your Media Ltd | Professional & scientific | 2023 |
| Social Your Retreat Ltd | Education | 2023 |
| Socialeyes (Chesterfield) Ltd | Health & social care | 2022 |
| Socium Distribution Ltd | Wholesale & retail | 2022 |
| Software Antelope Ltd | Wholesale & retail | 2015 |
| SOHAM03 Limited | Professional & scientific | 2025 |
| Solar 41 Limited | Construction | 2025 |
| Solar and Storage Limited | Energy | 2022 |
| Solarised Ltd | Construction | 2024 |
| Solid Fuel Association | Other services | 1994 |
| Solidcor Limited | Wholesale & retail | 2019 |
| Sol’S Staveley Limited | Hospitality | 2021 |
| Somero Enterprises Limited | Wholesale & retail | 2000 |
| Somersall Hall Estate Limited | Agriculture & fishing | 2015 |
| Somerville Associates Limited | Professional & scientific | 2018 |
| Sonar Data Ltd | Construction | 2007 |
| Sonia Baines Limited | Arts & recreation | 2025 |
| Sonke Agrisystems & Training Ltd | Construction | 2025 |
| Sopfadp Ltd | Real estate | 2026 |
| Sophie's Beauty Studio Ltd | Other services | 2025 |
| SOR Financial Consultants Limited | Financial services | 2016 |
| Sorbus Finance Limited | Administrative & support | 2022 |