| Social Chaos MCR Limited | Professional & scientific | 2026 |
| Social Motor Finance Ltd | Other services | 2019 |
| SOF Property Ltd | Real estate | 2026 |
| Sofiajade Living Limited | Real estate | 2025 |
| Sofiyas Collection Ltd | Wholesale & retail | 2023 |
| Softbox Limited | Information & communication | 1990 |
| Softdrive Solution Limited | Information & communication | 2021 |
| Softeq Laboratories Ltd | Information & communication | 2023 |
| Softpixel Ltd | Information & communication | 2026 |
| Software Installation Limited | Information & communication | 1985 |
| Sohaib Ahmed Ltd | Wholesale & retail | 2021 |
| Soim Limited | Real estate | 2025 |
| Solenoi UK Limited | Professional & scientific | 2018 |
| Soli Law Ltd | Professional & scientific | 2008 |
| Solus Brands Ltd | Wholesale & retail | 2026 |
| Solus Horizons Ltd | Information & communication | 2025 |
| Solved UK Consultancy Ltd | Extraterritorial | 2010 |
| Sona Mandhira International Corporation PVT Ltd | Wholesale & retail | 2022 |
| Sonac Limited | Extraterritorial | 2020 |
| Sonfx Group Ltd | Wholesale & retail | 2025 |
| Sonneti Fashions Limited | Professional & scientific | 1928 |
| Sons of the Prophet Network Diaspora CIC | Education | 2025 |
| Sonx Limited | Financial services | 2014 |
| Sonx Property Holdings Limited | Real estate | 2023 |
| Sopwell Lees Limited | Professional & scientific | 2008 |
| Soradiant Aesthetics Limited | Other services | 2021 |
| Sorbeterong Pinoy UK Ltd | Manufacturing | 2025 |
| Soren & Ahoora Limited | Wholesale & retail | 2021 |
| Sorra Clothing Ltd | Wholesale & retail | 2026 |
| SOS Pharmacist Ltd | Wholesale & retail | 2020 |
| Sou's Café Limited | Hospitality | 2022 |
| Soul Fitness Prestwich CIC | Education | 2025 |
| Soumil Medical Services Ltd | Professional & scientific | 2016 |
| Sounds About Right Productions Ltd | Arts & recreation | 2024 |
| Source Direct U.K. Ltd | Wholesale & retail | 2026 |
| South Cross Street MOT Centre Ltd | Manufacturing | 2017 |
| South Park Motors Ltd | Wholesale & retail | 2023 |
| Sovereign House GH | Health & social care | 2015 |
| Sovereign Ventures Ltd | Information & communication | 2025 |
| Soyler Investments Limited | Wholesale & retail | 2022 |
| SP Cleaning NW Limited | Administrative & support | 2026 |
| SP Commercials Limited | Wholesale & retail | 2016 |
| SP Therapy Services Limited | Health & social care | 2002 |
| Space Buddy Limited | Transport & logistics | 2026 |
| Space Face Ltd | Real estate | 2018 |
| Space Face Management Ltd | Real estate | 2021 |
| Spaces to Rent Ltd | Real estate | 2025 |
| Sparelink Ltd | Public administration | 2022 |
| Spark Creator Network Ltd | Professional & scientific | 2026 |
| Sparking Clogs Ltd | Wholesale & retail | 2025 |
| Sparkle Designer Ltd | Manufacturing | 2018 |
| Sparks of Strength Ltd | Health & social care | 2026 |
| Sparlclean Limited | Administrative & support | 2026 |
| Sparrowfire Ltd | Administrative & support | 2019 |
| Spartan Equipment Sales Limited | Administrative & support | 2021 |
| Spartan Valeting Ltd | Administrative & support | 2024 |
| SPC Entertainment Ltd | Arts & recreation | 2025 |
| SPC Express Limited | Information & communication | 2018 |
| Speakez Ltd | Arts & recreation | 2014 |
| Speakman & Sons Ltd | Real estate | 2025 |
| Speakmans Construction Limited | Construction | 2002 |
| Special OPS Limited | Administrative & support | 2025 |
| Specialised Lighting Company Ltd | Wholesale & retail | 2010 |
| Specialised Steel Haulage Limited | Transport & logistics | 2012 |
| Specialist Lines International Limited | Financial services | 2024 |
| Specialist Lines Limited | Financial services | 2017 |
| Specialist Switchgear Systems Limited | Manufacturing | 1984 |
| Speciality Medical Devices Limited | Wholesale & retail | 2013 |
| Spectra Shift Autos Ltd | Wholesale & retail | 2025 |
| Spectrum Property Ltd | Real estate | 2023 |
| Spectrum Workwear Ltd | Manufacturing | 2022 |
| Speech Therapy by Laura Ltd | Public administration | 2026 |
| Speedy Fuels Limited | Wholesale & retail | 2011 |
| Speedy Service 2000 Ltd | Transport & logistics | 2019 |
| Spencers A&A Limited | Professional & scientific | 2014 |
| Spenside Developments Ltd | Real estate | 2017 |
| Spenside Management Company Limited | Households | 2018 |
| Spexnation Limited | Health & social care | 2014 |
| SPI Surveillance, Protection & Investigation Ltd | Administrative & support | 2018 |
| Spice Garden Ramsbottom Ltd | Hospitality | 2022 |
| Spicy Chef 1 Ltd | Hospitality | 2025 |
| Spillard Homes Ltd | Real estate | 2025 |
| Spin X MCR Ltd | Arts & recreation | 2026 |
| Spinger Limited | Wholesale & retail | 2020 |
| SPJ Electrical Installation Limited | Construction | 2017 |
| Splashings of Love Limited | Manufacturing | 2013 |
| Spmu by Candice Ltd | Other services | 2025 |
| SPN Trading Limited | Wholesale & retail | 2011 |
| Sponge and Cream Ltd | Wholesale & retail | 2011 |
| Spontera Ltd | Professional & scientific | 2026 |
| Sportotal Limited | Health & social care | 2003 |
| Spot Investments Ltd | Real estate | 2022 |
| Spot Promotions Limited | Wholesale & retail | 2002 |
| Spotless Cleaning Services (Reading) Limited | Administrative & support | 2023 |
| Spotlight Sessions Ltd | Professional & scientific | 2026 |
| Spout/Piper Management Company Limited | Households | 2026 |
| SPR Advisory Limited | Professional & scientific | 2025 |
| Spraytec Car Sales Ltd | Wholesale & retail | 2019 |
| Spraytec Paintworks Ltd | Wholesale & retail | 2022 |
| Spud Badshah Ltd | Hospitality | 2025 |