| Spec-Ops Vehicle Logistics Limited | Transport & logistics | 2026 |
| Special Chaska Limited | Hospitality | 2021 |
| Special Equipment Supplies Limited | Administrative & support | 2017 |
| Special Projects London Limited | Construction | 2026 |
| Special Security K9 Ltd | Administrative & support | 2014 |
| Specialist Lc-Uk Limited | Construction | 2019 |
| Specialist Practice Ltd | Health & social care | 2026 |
| Specialist Vehicle Rental Limited | Transport & logistics | 2010 |
| Spector Inspection Consultancy Services Ltd | Construction | 2020 |
| Spector Limited | Real estate | 2003 |
| Spectral Pharmaceuticals Limited | Manufacturing | 2015 |
| Spectre Consulting Ltd | Information & communication | 2025 |
| Spectre Development Group Ltd | Real estate | 2025 |
| Spectrum Automotive Group Ltd | Wholesale & retail | 2018 |
| Spectrum Enterprise Solutions Ltd | Professional & scientific | 2024 |
| Spectrum Insights Management Ltd | Other services | 2025 |
| Spectrum Sales Ltd | Wholesale & retail | 2023 |
| Spectrumtradez Ltd | Wholesale & retail | 2024 |
| Speech and Language LAB Ltd | Other services | 2013 |
| Speed Consultants Limited | Professional & scientific | 2006 |
| Speed Express Limited | Transport & logistics | 2025 |
| Speed Fast Internet Cafe & Computers Limited | Wholesale & retail | 2024 |
| Speed Petro Ltd | Wholesale & retail | 2022 |
| Speed Property (Ilford) Ltd | Wholesale & retail | 2023 |
| Speed Property (London) Ltd | Real estate | 2013 |
| Speed Tiles Ltd | Other services | 2017 |
| Speedy Design & Build Limited | Construction | 2017 |
| Speedy Freight Services Ltd | Transport & logistics | 2024 |
| Speedy Pizza & Chicken Ltd | Hospitality | 2019 |
| Speedy Towing Traders & Recovery Ltd | Transport & logistics | 2024 |
| Speler UK Limited | Real estate | 2021 |
| Spellaura Limited | Wholesale & retail | 2025 |
| Sperrio Limited | Professional & scientific | 2016 |
| Spesoft Limited | Information & communication | 2005 |
| Spfix Ltd | Construction | 2018 |
| Spfp Trading Limited | Wholesale & retail | 2016 |
| Spgp Group Limited | Wholesale & retail | 2022 |
| SPH Services Ltd | Construction | 2023 |
| Sphere Property Management Ltd | Real estate | 2026 |
| Sphere PUB Company Ltd | Hospitality | 2017 |
| SPHERE9 Ltd | Professional & scientific | 2007 |
| Sphiria Digital Ltd | Information & communication | 2025 |
| Spice Genie UK Ltd | Manufacturing | 2025 |
| Spice Horizon Ltd | Hospitality | 2025 |
| Spice HUT Abbots Ltd | Hospitality | 2025 |
| Spice HUT ASK Ltd | Hospitality | 2025 |
| Spice HUT Express (213) Ltd | Hospitality | 2023 |
| Spice HUT Express (Ilford) Ltd | Hospitality | 2018 |
| Spice HUT Gants Limited | Hospitality | 2025 |
| Spice Khazana Restaurant Ltd | Hospitality | 2025 |
| Spice Lounge Faversham Ltd | Hospitality | 2024 |
| Spicebazaruk Ltd | Wholesale & retail | 2022 |
| Spicy Junction Ltd | Hospitality | 2025 |
| Spicy Peri & Grill Ltd | Hospitality | 2025 |
| Spikes Interactive Limited | Information & communication | 2017 |
| Spikes Ventures Limited | Real estate | 2020 |
| Spilsby Javs Limited | Health & social care | 2019 |
| Spine and Shine Health Ltd | Administrative & support | 2018 |
| Spinning Hamster Limited | Information & communication | 2025 |
| Spire Home Care & Training Limited | Health & social care | 2019 |
| Spirestar London Limited | Professional & scientific | 2016 |
| Spirit IT Services Ltd | Information & communication | 2022 |
| Spirit of Ukraine Ltd | Administrative & support | 2016 |
| Spirit UK Managed Services Ltd | Information & communication | 2009 |
| SPK Group Holdings Limited | Financial services | 2025 |
| SPK3 Properties Ltd | Real estate | 2019 |
| SPK3 Residential Ltd | Real estate | 2021 |
| Splash Energy Limited | Other services | 2018 |
| Splendid Cleaners Ltd | Administrative & support | 2025 |
| Splendid Icon Tech Limited | Wholesale & retail | 2017 |
| Splendoor Homes Ltd | Real estate | 2026 |
| Splendoor Stays Ltd | Real estate | 2026 |
| Splentech Limited | Wholesale & retail | 2026 |
| Splice Tech Limited | Information & communication | 2011 |
| Splicerise Ltd | Professional & scientific | 2026 |
| SPM Projects Ltd | Administrative & support | 2017 |
| SPM Quantity Surveying Ltd | Professional & scientific | 2024 |
| Spob Financials Limited | Financial services | 2011 |
| Spoke Cafe Limited | Hospitality | 2020 |
| Spooner Meals Catering Limited | Hospitality | 2025 |
| Spoorthy Services Ltd | Professional & scientific | 2022 |
| Sporadicate Limited | Water & waste | 2025 |
| Sporting Pillars C.I.C. | Arts & recreation | 2019 |
| Sports Content Provider Limited | Information & communication | 2010 |
| Sports Premium Limited | Wholesale & retail | 2019 |
| Sportsinsane | Health & social care | 2019 |
| Spot Coffee 353 Ltd | Hospitality | 2026 |
| Spot Stamp (Property) Limited | Real estate | 2022 |
| Spot Trade Ltd | Financial services | 2025 |
| Spotless Klean Ltd | Administrative & support | 2023 |
| Spotless Works Limited | Administrative & support | 2025 |
| Spraytech Autos Ltd | Wholesale & retail | 2012 |
| Sprd Decorators Limited | Construction | 2015 |
| Sprd Maintenance Limited | Construction | 2024 |
| Spreet Construction Limited | Construction | 2018 |
| Spring Care Home Services Limited | Health & social care | 2024 |
| Spring Deif Interior Limited | Construction | 2016 |
| Spring Farm RM4 Limited | Real estate | 2025 |
| Spring Valley Care Home Limited | Education | 2004 |
| Springclay Services Limited | Real estate | 1985 |