| Sentix Ltd | Information & communication | 2023 |
| Sequential Consultancy Services Ltd | Professional & scientific | 2021 |
| Sequential Professional Services Ltd | Professional & scientific | 2013 |
| Serema Properties Limited | Real estate | 2025 |
| Serena Relations Ltd | Hospitality | 2024 |
| Serendipity Food Solutions Group Ltd | Professional & scientific | 2020 |
| Serenity Grove Residential Care Ltd | Health & social care | 2025 |
| Serenity in Motion Limited | Other services | 2025 |
| Serenity Jane Counselling Ltd | Health & social care | 2025 |
| Serf Properties (South Norwood) Limited | Real estate | 2020 |
| Sertex Label and Printing Ltd | Manufacturing | 2026 |
| Services Resumed Limited | Administrative & support | 2003 |
| Servizio IT Ltd | Information & communication | 2023 |
| Sesh&Co Ltd | Real estate | 2025 |
| Sesl Consultancy Ltd | Information & communication | 2012 |
| SET1 Technologies Ltd | Information & communication | 2022 |
| Seth Stein Architects Limited | Professional & scientific | 2005 |
| Settlelink Ltd | Information & communication | 2026 |
| Sevenfields Primary Care Network Ltd | Health & social care | 2022 |
| Sevenoaks Nursery Ltd | Health & social care | 2024 |
| Sevenoaks Plumbing by Carl Robinson Ltd. | Construction | 2023 |
| Seventeen Twenty Nine Limited | Information & communication | 2024 |
| Seventh Moat Housing Company Limited | Households | 1982 |
| Severin Court (London) RTM Company Limited | Real estate | 2025 |
| Seymour Mansions (London) RTM Company Limited | Real estate | 2022 |
| SEZ Digital Ltd | Wholesale & retail | 2026 |
| SEZ10 Limited | Extraterritorial | 2024 |
| SF Vision Accelerator Coaching Ltd | Professional & scientific | 2023 |
| Sfhvj Limited | Administrative & support | 2017 |
| Sftk Ltd | Real estate | 2017 |
| SG Training Ltd | Education | 2023 |
| SG7 Ltd | Real estate | 2025 |
| SGBR2 Management Company Limited | Administrative & support | 2008 |
| SGC Construction Ltd | Construction | 2022 |
| SGF Engineering Ltd | Construction | 2018 |
| SGG Services Ltd | Transport & logistics | 2026 |
| SH Compliance & Maintenance Ltd | Real estate | 2025 |
| Shabeminding Ltd | Administrative & support | 2023 |
| Shabu House Management Limited | Real estate | 1986 |
| Shadowlens Studios Ltd | Professional & scientific | 2025 |
| Shaero Technology Limited | Information & communication | 2022 |
| Shahid Family Limited | Real estate | 2017 |
| Shainika (UK) Limited | Wholesale & retail | 2020 |
| Shake IT! Sauce Ltd | Manufacturing | 2025 |
| Shakelicious Ltd | Hospitality | 2020 |
| Shakespeare Interiors (UK) Ltd | Construction | 2011 |
| Shakthi Retail Ltd | Wholesale & retail | 2025 |
| Shamash Trade (U.K.) Limited | Extraterritorial | 2005 |
| Shampan Bromley Ltd | Hospitality | 2023 |
| Shan Bexleyheath Limited | Wholesale & retail | 2026 |
| Shan Groceries Ltd | Wholesale & retail | 2023 |
| Shanmugarajah Ltd | Hospitality | 2022 |
| Shanna in Property Ltd | Administrative & support | 2021 |
| Shape Strategies Ltd | Professional & scientific | 2025 |
| Sharesolve Ltd | Professional & scientific | 2024 |
| Shark Optical Limited | Health & social care | 2008 |
| Shawarmore Ltd | Hospitality | 2025 |
| Shawfield Capital Partners Limited | Professional & scientific | 2024 |
| Shay Shack Investment Company Limited | Real estate | 2023 |
| Shaytrev Automobile Ltd | Wholesale & retail | 2019 |
| Shea Perfection Limited | Other services | 2019 |
| Sheil Land Associates Limited | Administrative & support | 1962 |
| Sheldonian Holdings Ltd | Administrative & support | 2018 |
| Shelectrics Electrical Services Ltd | Construction | 2023 |
| Shepton Houses Residents Limited | Households | 2000 |
| Sheredes Ltd | Financial services | 2013 |
| Sherlocks Valuers & Auctioneers Limited | Other services | 2007 |
| Sherry Bevan Consulting Limited | Information & communication | 2012 |
| Shield Creates Limited | Information & communication | 2026 |
| Shift Happens Ltd | Water & waste | 2024 |
| Shikharaa Properties Limited | Construction | 2017 |
| Shimmer Ltd | Wholesale & retail | 2019 |
| Shinoda Ltd | Professional & scientific | 2023 |
| Ships & Lighthouse Properties Ltd | Real estate | 2026 |
| Shirley Lodge Mansions Limited | Real estate | 2003 |
| Shivakhadirvel Ltd | Wholesale & retail | 2023 |
| Shivba Limited | Public administration | 2024 |
| SHL Care Ltd | Health & social care | 2024 |
| Shmile Ltd | Health & social care | 2022 |
| Shmoo Property Limited | Real estate | 2020 |
| Sholaak Ltd | Information & communication | 2018 |
| Shona Crooks Ltd | Administrative & support | 2024 |
| Shoot Solutions Ltd | Professional & scientific | 2016 |
| Shortlands Advisory Limited | Financial services | 2018 |
| Shortlands Business Services Limited | Professional & scientific | 2026 |
| Shortlands Computing Ltd | Information & communication | 2007 |
| Shortlands Consultancy Ltd | Financial services | 2023 |
| Shortlands Holdings Limited | Other services | 2021 |
| Shortlands Market CIC | Wholesale & retail | 2021 |
| Shortlands Property Management Limited | Households | 1998 |
| Shortlands Supermarket Ltd | Wholesale & retail | 2020 |
| Shortlands Transport Limited | Transport & logistics | 2013 |
| Shortlands Tutors Limited | Education | 2025 |
| Shotlands Ltd | Hospitality | 2024 |
| Show Business International Management Ltd | Professional & scientific | 2019 |
| Show NO.1 Limited | Professional & scientific | 2015 |
| Showell Consulting Limited | Professional & scientific | 2023 |
| Shunfa London Ltd | Hospitality | 2024 |
| Sibc Developments (London) Limited | Real estate | 2015 |
| Sibook Ltd | Information & communication | 2025 |