| Skyline Glass Limited | Manufacturing | 2024 |
| Skyline Health and Travel Ltd | Health & social care | 2022 |
| Skyline LAB Ltd | Health & social care | 2022 |
| Skyline Prestige Services Ltd | Hospitality | 2026 |
| Skyline Property Hub Limited | Real estate | 2023 |
| Skyline Rentals Ltd | Real estate | 2018 |
| Skymurti Ltd | Administrative & support | 2014 |
| Skynet Cyber Consulting Limited | Information & communication | 2015 |
| Skynet Traders Ltd | Wholesale & retail | 2025 |
| Skyreach Homes Limited | Real estate | 2023 |
| Skyreach IT Solutions Ltd | Information & communication | 2025 |
| Skyrise International CIC | Public administration | 2026 |
| Skyscraper 99 Ltd | Professional & scientific | 2016 |
| Skyshift Digital Limited | Information & communication | 2025 |
| Skyspace Commercial Limited | Construction | 2021 |
| Skyspace Homes Limited | Construction | 2010 |
| Skyspace Properties Limited | Construction | 2013 |
| Skytek London Ltd | Wholesale & retail | 2024 |
| Skywards Aviation Consultants Ltd | Professional & scientific | 2009 |
| SL Group Limited | Hospitality | 2019 |
| SL Motor Group Ltd | Wholesale & retail | 2016 |
| Sl-Complete Limited | Wholesale & retail | 2011 |
| SL3B Limited | Financial services | 2022 |
| SLA Properties Limited | Real estate | 2017 |
| Slacker Creative Limited | Other services | 2014 |
| Slate Space Ltd | Construction | 2019 |
| SLC Autos Ltd | Wholesale & retail | 2023 |
| SLD Consultant Limited | Information & communication | 2025 |
| SLD Topco Limited | Financial services | 2024 |
| Slebech Park Estate Ltd | Hospitality | 2013 |
| Sleek Brows Ltd | Other services | 2013 |
| Sleek Safe Secure Ltd | Construction | 2025 |
| Sleekpad Limited | Wholesale & retail | 2022 |
| Sleepwell Bedrooms Limited | Wholesale & retail | 2005 |
| Slegacy 19 Construction Ltd | Construction | 2026 |
| SLF Locksmiths and Carpentry Ltd | Construction | 2022 |
| SLG Durga Ltd | Real estate | 2021 |
| SLH Interiors Limited | Construction | 2019 |
| Sliced & Diced Limited | Hospitality | 2008 |
| Sliceology Sunderland Limited | Hospitality | 2021 |
| Slick Chick Ltd | Hospitality | 2025 |
| Slick MO Entertainment Ltd | Information & communication | 2018 |
| Slide Samurai Ltd | Professional & scientific | 2024 |
| Sliktek Ltd | Information & communication | 2023 |
| Slims Place Limited | Wholesale & retail | 2015 |
| SLJ Foodservice Ltd | Wholesale & retail | 2020 |
| SLM Trading Limited | Administrative & support | 2004 |
| Slmmx Ltd | Other services | 2020 |
| SLN Investments Limited | Real estate | 2023 |
| Sloane Harbour Holdings Limited | Financial services | 2021 |
| SLP UK Property Limited | Real estate | 2022 |
| SLR Thurka Ltd | Real estate | 2021 |
| SLS 360 Limited | Professional & scientific | 2022 |
| Slsp Software Solutions Limited | Information & communication | 2012 |
| SM and AK Limited | Professional & scientific | 2019 |
| SM Apex Holdings Limited | Health & social care | 2026 |
| SM Auto Repairs Limited | Wholesale & retail | 2019 |
| SM CAP Ltd | Financial services | 2018 |
| SM CRN Ltd | Administrative & support | 2025 |
| SM Events & Entertainment Ltd | Information & communication | 2023 |
| SM Fast Limited | Transport & logistics | 2020 |
| SM Maintenance Group Ltd | Administrative & support | 2024 |
| SM VTH Construction Ltd | Construction | 2022 |
| SM10STUDIO Architecture Ltd | Professional & scientific | 2023 |
| Small Business Advisory Limited | Professional & scientific | 2022 |
| Small Giants Records Ltd. | Administrative & support | 2008 |
| Small MAN Called MIN Ltd | Professional & scientific | 2019 |
| Smallbone Family Partnership LLP | | 2022 |
| Smallford Business Park Limited | Real estate | 2021 |
| Smallgears Limited | Professional & scientific | 1996 |
| Smarnama Limited | Health & social care | 2011 |
| Smart Advisory Solutions Ltd | Financial services | 2018 |
| Smart Air Control Systems Ltd | Energy | 2022 |
| Smart Automotive Solutions Ltd | Wholesale & retail | 2026 |
| Smart Bits Ltd | Information & communication | 2013 |
| Smart Bright Light Ltd | Construction | 2024 |
| Smart Brothers Property Holdings Ltd | Real estate | 2018 |
| Smart Capital Limited | Real estate | 2023 |
| Smart Child Limited | Education | 2019 |
| Smart Choice Cars Ltd | Administrative & support | 2019 |
| Smart Choice Services Ltd | Professional & scientific | 2019 |
| Smart Code Consultancy Limited | Information & communication | 2017 |
| Smart Concept Design Ltd | Construction | 2021 |
| Smart Consultancy Solutions Ltd | Real estate | 2019 |
| Smart Cord Electricals Ltd | Construction | 2018 |
| Smart Digicom Ltd | Information & communication | 2018 |
| Smart Dispensing Ltd | Wholesale & retail | 2026 |
| Smart Domicile Ltd | Real estate | 2022 |
| Smart Driving School Ltd | Education | 2023 |
| Smart Eco Homes Ltd | Construction | 2023 |
| Smart Education Group Ltd | Education | 2016 |
| Smart Express Trading Ltd | Wholesale & retail | 2022 |
| Smart Feet Limited | Health & social care | 2026 |
| Smart Heating Systems Ltd | Construction | 2015 |
| Smart Investment LDN Ltd | Real estate | 2018 |
| Smart Ladies Ltd | Administrative & support | 2018 |
| Smart Learning London Ltd | Education | 2025 |
| Smart Leasing (UK) Ltd | Professional & scientific | 2019 |
| Smart Line Marketing International Ltd | Professional & scientific | 2025 |
| Smart Matrix Intellectual Property Limited | Health & social care | 2014 |