| Skinspection Lounge Ltd | Professional & scientific | 2023 |
| Skinturale Ltd | Education | 2024 |
| SKK Medical Consulting Services Limited | Professional & scientific | 2024 |
| SKK Property Investment Ltd | Real estate | 2024 |
| SKL Professional Recruitment Agency Limited | Health & social care | 1999 |
| Skml Medical Ltd | Wholesale & retail | 2023 |
| SKP Property Partners LLP | | 2025 |
| SKP Software Ltd | Information & communication | 2023 |
| Skpx Consulting Limited | Public administration | 2025 |
| SKR Consultancy Ltd | Professional & scientific | 2016 |
| Sksoftware Consultancy Limited | Information & communication | 2011 |
| Sky Haven Holding Ltd | Financial services | 2023 |
| Sky Haven Ltd | Professional & scientific | 2023 |
| Sky High Solutions Ltd | Information & communication | 2013 |
| Sky Link Parking Services Ltd | Transport & logistics | 2025 |
| Sky Logic Solutions Limited | Information & communication | 2014 |
| Sky Medical Services Limited | Health & social care | 2021 |
| Sky Naturals Ltd | Other services | 2025 |
| Sky of London Properties Ltd | Real estate | 2025 |
| Skyasure Limited | Transport & logistics | 2022 |
| Skyblue Mobile Tyres Ltd | Wholesale & retail | 2026 |
| Skybsure Ltd | Hospitality | 2023 |
| Skyclimb Access Limited | Construction | 2023 |
| Skycrescent Stores Limited | Wholesale & retail | 2020 |
| Skyhub Trading Ltd | Wholesale & retail | 2025 |
| Skyla Property Limited | Real estate | 2023 |
| Skynetics Consulting Ltd | Information & communication | 2025 |
| Skyphase Limited | Information & communication | 1986 |
| Skyreal Property Management Limited | Professional & scientific | 1991 |
| Skyridge Solutions Limited | Real estate | 2002 |
| Skystar Stores Limited | Wholesale & retail | 2021 |
| SL Housing Ltd | Real estate | 2021 |
| Slambjams Investment Limited | Financial services | 2023 |
| SLE Consulting Ltd | Health & social care | 2025 |
| Sleepwell Homes Limited | Real estate | 2019 |
| Sleepwell-Lets Limited | Real estate | 2025 |
| SLG Electrical Services Ltd | Construction | 2026 |
| SLI Site Services Ltd | Transport & logistics | 2026 |
| Slicez Ltd | Hospitality | 2025 |
| Slick Entertainment Ltd | Hospitality | 2023 |
| Sligo Properties (Wessex Drive) Limited | Real estate | 2018 |
| Sligo Properties Limited | Real estate | 2005 |
| Slimbridge Steel Solutions Ltd | Construction | 2017 |
| Sloane Marylebone Ltd | Professional & scientific | 2016 |
| Sloane Residents Limited | Households | 1974 |
| Slone Capital Consulting Limited | Financial services | 2018 |
| Slowsteady&Limited Ltd. | Transport & logistics | 2021 |
| SLT Enterprise Ltd | Financial services | 2026 |
| SM 365 Ltd | Health & social care | 2019 |
| SM Legal Consultancy Ltd | Professional & scientific | 2022 |
| SM Prime Estate Ltd | Real estate | 2024 |
| SM Sofa and Chair Ltd | Manufacturing | 2025 |
| SM Sons Grocers Ltd | Wholesale & retail | 2019 |
| SM Sons Properties Ltd | Real estate | 2024 |
| SMA Care Limited | Health & social care | 2014 |
| Small Dark Woodland Creature Productions Limited | Arts & recreation | 2015 |
| Smart (MP) Property Ltd | Real estate | 2004 |
| Smart (SD) Property Ltd | Real estate | 2004 |
| Smart AI Holdings Limited | Information & communication | 2024 |
| Smart ALS General Services Ltd | Administrative & support | 2019 |
| Smart Bridge Ltd | Education | 2026 |
| Smart Cars Watford Limited | Transport & logistics | 2015 |
| Smart Chemistry Limited | Other services | 2018 |
| Smart Connection Ltd | Information & communication | 2017 |
| Smart Contract Management Solutions Limited | Information & communication | 2013 |
| Smart Covers Ltd | Construction | 2025 |
| Smart IT Resources Limited | Information & communication | 2001 |
| Smart Lanka Apparels Ltd | Wholesale & retail | 2023 |
| Smart Lanka Cleaners Limited | Administrative & support | 2025 |
| Smart Offshore Solutions Ltd | Professional & scientific | 2025 |
| Smart Property Deals Ltd | Real estate | 2021 |
| Smart Service Windows Ltd | Administrative & support | 2025 |
| Smart Used Cars Limited | Wholesale & retail | 2019 |
| Smart Wheel Autos Ltd | Wholesale & retail | 2022 |
| Smart Wheel Motors Ltd | Wholesale & retail | 2019 |
| Smartc Digital Ltd | Information & communication | 2025 |
| Smartcash (Watford) Ltd | Wholesale & retail | 2014 |
| Smartchoice Solutions Limited | Administrative & support | 2019 |
| Smartdeal Marketing Limited | Professional & scientific | 2018 |
| Smartfix Heating Ltd | Other services | 2017 |
| Smartgen Technology Ltd | Other services | 2023 |
| Smartnet Systems Ltd | Information & communication | 2026 |
| Smartpoint Consulting Ltd | Professional & scientific | 2023 |
| Smash Industries Ltd | Administrative & support | 2023 |
| Smashshack Ltd | Hospitality | 2019 |
| SMB Care Consultancy Limited | Public administration | 2023 |
| SMC Floor Fitters Ltd | Construction | 2026 |
| Smd&Me Ltd | Real estate | 2019 |
| SME Transport Ltd | Transport & logistics | 2017 |
| SMILE247 Limited | Health & social care | 2026 |
| Smith & Nephew (Overseas) Limited | Professional & scientific | 1961 |
| Smith & Nephew Beta Limited | Professional & scientific | 1929 |
| Smith & Nephew China Holdings UK Limited | Professional & scientific | 2014 |
| Smith & Nephew Employees Trustees Limited | Administrative & support | 2001 |
| Smith & Nephew ESN Limited | Administrative & support | 2005 |
| Smith & Nephew Finance | Administrative & support | 2001 |
| Smith & Nephew Finance Oratec | Administrative & support | 2002 |
| Smith & Nephew Investment Holdings Limited | Professional & scientific | 1943 |
| Smith & Nephew L.P. | | 2026 |
| Smith & Nephew Lilia Limited | Professional & scientific | 1947 |