| Silvi Enterprise Ltd | Real estate | 2026 |
| SIR DV Holdings Ltd | Financial services | 2023 |
| Site Ready Solutions Limited | Administrative & support | 2024 |
| SIX Nurturing Haven Limited | Health & social care | 2026 |
| Sixrq Ltd. | Information & communication | 1993 |
| Sixth Scent Ltd | Wholesale & retail | 2023 |
| SJW Motor Services Limited | Wholesale & retail | 2017 |
| SKL Asbestos Removal Contracts Ltd | Water & waste | 2016 |
| Slate Limited | Wholesale & retail | 2004 |
| SLG Safety Services Ltd | Professional & scientific | 2014 |
| SLR Care Consultancy Limited | Professional & scientific | 2024 |
| Smart Relocation Experts Ltd | Hospitality | 2025 |
| Smaxi Engineering Limited | Construction | 2019 |
| SMC Financial Limited | Professional & scientific | 2024 |
| Smiths Accountancy Services Limited | Professional & scientific | 1997 |
| SMN Future Investments Ltd | Real estate | 2025 |
| Smooth Moves Removals Ltd | Transport & logistics | 2019 |
| Sna-Uk Limited | Information & communication | 2025 |
| SNC Traders Ltd | Manufacturing | 2025 |
| SNL Construction Limited | Construction | 2022 |
| SO Very Limited | Information & communication | 2014 |
| Sochmie Ltd | Real estate | 2023 |
| Sofoliver Limited | Real estate | 2024 |
| Softman Ltd | Professional & scientific | 2012 |
| Soldier Solutions Limited | Other services | 2023 |
| Solo Asbestos Consultants Limited | Water & waste | 2017 |
| Solospace Group Limited | Other services | 2020 |
| Somerfield Stores Limited | Wholesale & retail | 2024 |
| Something to Remember ME by Ltd | Extraterritorial | 2008 |
| Sonar Search IT Limited | Administrative & support | 2018 |
| Sonucreativeco Limited | Professional & scientific | 2025 |
| Sophisti-Cuts by Helen Jane Ltd | Other services | 2025 |
| South East Promo Swipe Ltd | Wholesale & retail | 2019 |
| South Eastern UK Limited | Construction | 2004 |
| South Essex Vision Limited | Health & social care | 1996 |
| South Stars Entertainment Ltd | Arts & recreation | 2018 |
| Southern Pipelines Ltd | Professional & scientific | 2026 |
| Southwood Design Services Limited | Administrative & support | 1981 |
| SP Electrical Limited | Construction | 2024 |
| SP Services & Consultancy Ltd | Construction | 2025 |
| Sparkles Gymnastics Limited | Arts & recreation | 2022 |
| Spatula & Spoon Limited | Hospitality | 2023 |
| SPB Air Conditioning Limited | Construction | 2023 |
| Specialist (UK) Limited | Construction | 2000 |
| Specialist Car Care Services Limited | Administrative & support | 1996 |
| Specialist Car Cleaning Services Limited | Other services | 1996 |
| Specialist Land Limited | Construction | 2000 |
| Spectra Asbestos Services Limited | Extraterritorial | 2016 |
| Spectrum Fire and Security Group Ltd | Construction | 2017 |
| Speedy Trans Ltd | Transport & logistics | 2023 |
| Spicecombo Limited | Wholesale & retail | 2015 |
| Spicepro Ltd | Wholesale & retail | 2022 |
| Spoon & Spatula Limited | Hospitality | 2023 |
| Sportivoo Ltd | Information & communication | 2021 |
| Sports - Inc CIC | Education | 2026 |
| Sports 9 Golf Limited | Arts & recreation | 2021 |
| Spot on K9 Limited | Information & communication | 2025 |
| Spring Services Ltd | Other services | 2025 |
| Springrove Beacon Ltd | Real estate | 2025 |
| Springrove Estates Ltd | Real estate | 2021 |
| Springrove Livingstone Ltd | Real estate | 2024 |
| Springwell Homes Limited | Real estate | 2024 |
| Sprint Mobile Solutions Limited | Information & communication | 2002 |
| Squires Coffee Shop Limited | Hospitality | 2002 |
| SRC Financial Services Limited | Financial services | 2005 |
| SRC Mortgage Solutions Limited | Professional & scientific | 2024 |
| SS6 Containers Ltd | Transport & logistics | 2025 |
| SS8 Accounting Ltd | Professional & scientific | 2021 |
| SS8 Combatfit Limited | Arts & recreation | 2024 |
| SS8 Contracts Limited | Construction | 2018 |
| SS8 Property Management Limited | Real estate | 2018 |
| SS8 Trading Limited | Arts & recreation | 2025 |
| ST Osyths Properties Limited | Households | 2022 |
| Stacyann Limited | Public administration | 2023 |
| Stanley Malcolm George Rouse Ltd | Extraterritorial | 2023 |
| Stanmore Express Ltd | Wholesale & retail | 2024 |
| Starburst Effects Ltd | Arts & recreation | 2022 |
| Starkey Industries Limited | Information & communication | 2015 |
| Starrucks Estates Ltd | Real estate | 2026 |
| Starstruck Productions Limited | Information & communication | 2018 |
| Steel Crew Limited | Construction | 2023 |
| Stellar Steel & Fabrication Limited | Construction | 2022 |
| Stonebridge Goods Ltd | Wholesale & retail | 2025 |
| Strips&Flips Limited | Wholesale & retail | 2025 |
| Strive Certification Limited | Professional & scientific | 2025 |
| Strive Global Limited | Professional & scientific | 2023 |
| Structural & Personnel Services Limited | Construction | 2001 |
| Strvng Limited | Wholesale & retail | 2025 |
| Studio SIA UK Ltd | Arts & recreation | 2025 |
| STW ETE Co Limited | Other services | 2014 |
| STW FM Ltd | Transport & logistics | 2006 |
| STW HGV Limited | Transport & logistics | 2009 |
| STW Vans and Couriers Limited | Transport & logistics | 2009 |
| SUB12 Airgun Club Ltd | Arts & recreation | 2026 |
| Subento Services Ltd | Health & social care | 2022 |
| Subpub Limited | Real estate | 2019 |
| Succeeder Recovery Ltd | Wholesale & retail | 2024 |
| SUGAR23 Ltd | Hospitality | 2026 |
| Sukkah Estates Ltd | Real estate | 2022 |
| Summit Search Group Ltd | Administrative & support | 2017 |