| Strategic Wealth Planning Limited | Financial services | 2013 |
| Stratton Contractors Ltd | Other services | 2016 |
| Streams Consultancy Ltd | Professional & scientific | 2026 |
| Strongtower Cleaning Services Ltd | Administrative & support | 2025 |
| Structural Works Developments Ltd | Real estate | 2016 |
| Structural Works Ltd | Professional & scientific | 2012 |
| STS Estates Ltd | Real estate | 2020 |
| Sttrn Ltd | Hospitality | 2018 |
| STU the Detailer Limited | Other services | 2013 |
| Stuart Barton-Hagger Limited | Wholesale & retail | 2002 |
| Studio 53 Productions Limited | Manufacturing | 2018 |
| Studio Kojan Ltd | Information & communication | 2021 |
| Studio Souffle Ltd | Manufacturing | 2012 |
| Studio Spritz Limited | Professional & scientific | 2024 |
| Studio Vienna Limited | Arts & recreation | 2026 |
| Study Hub Consultancy Limited | Professional & scientific | 2026 |
| Styles Flooring Contractors (Great Wakering) Ltd | Construction | 1990 |
| Styling Spaces Interior Design Limited | Professional & scientific | 2024 |
| Styx River Ltd | Information & communication | 2015 |
| SUB City Music Limited | Professional & scientific | 2013 |
| Subco 0805 Ltd | Professional & scientific | 2023 |
| Success Business Ventures Limited | Information & communication | 2001 |
| Success Resources UK Limited | Professional & scientific | 2008 |
| Successone UK Limited | Professional & scientific | 2023 |
| Suffolk Prestige Competition Limited | Other services | 2026 |
| Suits and Boots Limited | Professional & scientific | 2022 |
| Summer Systems Limited | Professional & scientific | 1997 |
| Summer Time Clothing Ltd | Manufacturing | 2021 |
| Summers Care Ltd | Health & social care | 2025 |
| Summit Laundry Ltd | Other services | 2025 |
| Sumodi Ltd | Professional & scientific | 2019 |
| Sumogo Limited | Transport & logistics | 2016 |
| Sun Autos Limited | Wholesale & retail | 2012 |
| Sun Motors Limited | Wholesale & retail | 1938 |
| Sundrift Limited | Real estate | 2025 |
| Sunflower Student & Residential Lettings Limited | Real estate | 2024 |
| Sunglasses NOW Ltd | Wholesale & retail | 2025 |
| Sunna Shot Ltd | Manufacturing | 2025 |
| Sunningdale Court RTM Company Limited | Real estate | 2019 |
| Sunnymed Limited | Health & social care | 2015 |
| Sunray Limited | Hospitality | 2025 |
| Sunrisefm London Ltd | Information & communication | 2022 |
| Sunstone M&C Ltd | Professional & scientific | 2024 |
| SUP Skills Ltd | Education | 2022 |
| Super Flaming Grill Ltd | Hospitality | 2025 |
| Super Foods EN Ltd | Hospitality | 2019 |
| Super Kebab and Shawarma Ltd | Hospitality | 2025 |
| Super Pro Limited | Health & social care | 2014 |
| Superhdtb Ltd | Hospitality | 2019 |
| Superhuman Assistants Ltd | Administrative & support | 2025 |
| Superior Nails Ltd | Other services | 2024 |
| Supply That Limited | Extraterritorial | 2020 |
| Support Legal Limited | Information & communication | 2016 |
| Supremacy of the Mind CIC | Wholesale & retail | 2022 |
| Supreme Holidays Ltd | Transport & logistics | 2015 |
| Surely Yours Healthcare Ltd | Health & social care | 2022 |
| Surf Healthcare Ltd | Health & social care | 2014 |
| Surf Properties Ltd | Real estate | 2022 |
| Surjkl Ltd | Health & social care | 2023 |
| Surma Inc Ltd | Hospitality | 2018 |
| SUS UK Services Ltd. | Wholesale & retail | 2020 |
| Sussex Fields (Two) Management Company Limited | Households | 1993 |
| Sustainable Agriculture Provider Limited | Administrative & support | 2012 |
| Sutton and Smith Limited | Manufacturing | 1963 |
| Sutton Renovations Limited | Professional & scientific | 2016 |
| Sutton Road Management Company Limited | Professional & scientific | 1988 |
| Sutton Road Repairs Limited | Wholesale & retail | 2020 |
| Suttons Local Limited | Wholesale & retail | 2020 |
| Suzanne Farris Consulting Limited | Health & social care | 2011 |
| SVM Installations Ltd | Construction | 2017 |
| SW Welding Ltd | Manufacturing | 2022 |
| Swatchways Residents Association Limited | Health & social care | 1974 |
| SWE Electrical Contractors Limited | Construction | 2002 |
| Swift Shield Windscreens Ltd | Wholesale & retail | 2026 |
| Swift-Support Ltd | Health & social care | 2024 |
| Swimtank (Friern Barnet) Limited | Arts & recreation | 2025 |
| Swimtank (Hampstead) Limited | Arts & recreation | 2026 |
| Swimtank Group Holdings 2 Limited | Financial services | 2026 |
| SWL Naval Design Ltd | Professional & scientific | 2017 |
| SX Hire Limited | Administrative & support | 2018 |
| SX Tools Ltd | Wholesale & retail | 2024 |
| SX3 Claims Limited | Professional & scientific | 2014 |
| Syclone Investments Ltd | Real estate | 2025 |
| Syclone Limited | Wholesale & retail | 2018 |
| SYL TEQ Limited | Wholesale & retail | 2023 |
| Sylheti Spice Ltd | Hospitality | 2019 |
| Sylvan Tech Limited | Information & communication | 2022 |
| Synergies Limited | Financial services | 2018 |
| Synergy Hybrid Fitness Ltd | Arts & recreation | 2024 |
| Syqrh Housing Ltd | Real estate | 2025 |
| T & O Drainage and Plumbing Ltd | Water & waste | 2018 |
| T & R Building Contractors Limited | Construction | 2013 |
| T & T Allard Ltd | Professional & scientific | 2024 |
| T B Cars Limited | Wholesale & retail | 2021 |
| T H Building & Landscaping Ltd | Construction | 2021 |
| T M E Consultancy Ltd | Information & communication | 2013 |
| T R Fossett Ltd | Wholesale & retail | 2005 |
| T R S Essex Limited | Real estate | 2025 |
| T S Wilmot Ltd | Education | 2019 |
| T&F Construction Ltd | Construction | 2025 |