| Spectre Asset Management Ltd | Other services | 2024 |
| Speech Therapy Club Ltd. | Health & social care | 2020 |
| Speechless Limited | Wholesale & retail | 2015 |
| Speedbrake Ltd | Information & communication | 2025 |
| Speedx Construct Ltd | Construction | 2025 |
| Speedy Gonzales Transport Limited | Manufacturing | 2024 |
| Speedy Scooters Ltd | Wholesale & retail | 2024 |
| SPEEDY3 Limited | Transport & logistics | 2019 |
| Spence Mcknight Property Limited | Real estate | 2025 |
| Spesso Food Limited | Hospitality | 2026 |
| Spesso Pizza Ltd | Hospitality | 2022 |
| Sphere Consultancy Services Ltd | Wholesale & retail | 2018 |
| Sphg Properties Limited | Hospitality | 2019 |
| Spice Garden 19 Ltd | Hospitality | 2019 |
| Spider Investments Limited | Real estate | 2025 |
| Spil Records Limited | Information & communication | 2025 |
| Spirited Science Ltd | Professional & scientific | 2026 |
| SPL Investment Holdings Ltd | Construction | 2020 |
| Splash Event Solutions Limited | Arts & recreation | 2010 |
| Splash VIK Painters Limited | Construction | 2025 |
| Splendour Automobiles Ltd | Wholesale & retail | 2020 |
| Sportsbase Limited | Information & communication | 2005 |
| Spot on Property Limited | Information & communication | 2015 |
| Spotnana Technology Ltd | Administrative & support | 2018 |
| Spring Court (Edgware) Limited | Households | 2001 |
| Spring View Group Ltd | Health & social care | 2017 |
| Spring View Health Group Ltd | Health & social care | 2020 |
| Spring Villa Park Limited | Real estate | 1988 |
| Springcom Ltd | Real estate | 2023 |
| Springhill Properties Ltd | Real estate | 2025 |
| Springsons (Edgware) Limited | Real estate | 2026 |
| Springsons (Weymouth) Ltd | Real estate | 2023 |
| Springsons Holdings Ltd | Real estate | 2022 |
| Springwood Healthcare Services Ltd | Administrative & support | 2009 |
| Springwood Silver Limited | Real estate | 2023 |
| Sprucelink Property Management Limited | Households | 1991 |
| Spudman Ltd | Hospitality | 2025 |
| Square Ocean Ltd | Hospitality | 2020 |
| Square the Circle Games Ltd | Professional & scientific | 2021 |
| SR Global Ltd | Real estate | 2016 |
| SRC Equity Limited | Professional & scientific | 2019 |
| SRI Emas Limited | Real estate | 2003 |
| SRI Fusion Bites Ltd | Hospitality | 2026 |
| SRI Sathya SAI Books (UK) Limited | Wholesale & retail | 1999 |
| SRI Thurkkaa Cash & Carry Limited | Wholesale & retail | 2016 |
| SRI Yogiraj Ltd | Other services | 2026 |
| Sriindra Limited | Wholesale & retail | 2019 |
| Srimadh Limited | Real estate | 2017 |
| Srota Limited | Administrative & support | 2012 |
| SRP Consulting Limited | Professional & scientific | 2022 |
| SRP Enterprises Limited | Administrative & support | 2009 |
| SS Optom Locum Ltd | Professional & scientific | 2019 |
| SS Pro-Pave Ltd | Construction | 2017 |
| SS RS Investments Ltd | Health & social care | 2024 |
| SS Securities Limited | Administrative & support | 2021 |
| Ss:Tt Places Limited | Construction | 2021 |
| SSA Limited | Other services | 2025 |
| Ssat Estate Ltd | Real estate | 2025 |
| SSD Circle Limited | Real estate | 2024 |
| Ssdaa Property Limited | Real estate | 2024 |
| Ssjk Investments UK Limited | Financial services | 2018 |
| Ssll Holdings Limited | Real estate | 2014 |
| Ssll Property Ltd | Real estate | 2014 |
| Sssdryliner Ltd | Construction | 2019 |
| ST Ann's Court (Hendon) RTM Company Limited | Households | 2007 |
| ST James Consultants Ltd | Professional & scientific | 2019 |
| ST Katherine Consortium 6 Limited | Construction | 2023 |
| ST Katherine Consortium 8 Limited | Construction | 2024 |
| ST Katherine Developments 2 Limited | Construction | 2023 |
| ST Katherine Group Limited | Construction | 2019 |
| ST Katherine Holdings Limited | Financial services | 2022 |
| ST Katherine Investment Group Limited | Financial services | 2013 |
| ST Katherine LLP | | 2010 |
| ST Katherine Management Limited | Real estate | 2020 |
| ST Katherine Padel Holdings Limited | Financial services | 2025 |
| ST Michael's Park Management Company Limited | Households | 2004 |
| ST Pancras Hotel GRP Limited | Hospitality | 2014 |
| ST Peter's Court Limited | Other services | 1999 |
| ST Peter's Pharmacy Limited | Wholesale & retail | 2011 |
| ST. Catherines Farm Court Residents Association Limited | Households | 1982 |
| ST. Mark's Flat Management Limited | Real estate | 1994 |
| ST. Richard Limited | Administrative & support | 2024 |
| STA Trustees Ltd | Professional & scientific | 2025 |
| Staffcareselect Ltd | Administrative & support | 2026 |
| Stage Control Limited | Manufacturing | 1967 |
| Stained Glass Restoration Limited | Construction | 2021 |
| Stal Drylining Ltd | Construction | 2018 |
| Stalborne Limited | Professional & scientific | 2025 |
| Staltor Limited | Professional & scientific | 2025 |
| Stalwin Limited | Professional & scientific | 2025 |
| Stamp Management Ltd | Professional & scientific | 2020 |
| Stanbridge Wealth Management Ltd | Financial services | 2010 |
| Standard Interiors Ltd | Construction | 2021 |
| Standard Investment Ltd | Real estate | 2025 |
| Standard Plumbing Services Ltd | Construction | 2022 |
| Stane Street Limited | Financial services | 2019 |
| Stanford Bridge Partners Ltd | Construction | 2024 |
| Stang-Lord Limited | Real estate | 2020 |
| Stanley Properties GB Limited | Real estate | 2012 |
| Stantondeliver Ltd | Real estate | 2009 |