| SE1 Films Ltd | Arts & recreation | 2024 |
| SE1 Taxi Rentals Ltd. | Transport & logistics | 2016 |
| SE10 Taxi Rentals Ltd | Transport & logistics | 2022 |
| SE11 Taxi Rentals Ltd | Transport & logistics | 2022 |
| SE12 Taxi Rentals Ltd | Transport & logistics | 2022 |
| SE13 Taxi Rentals Ltd | Transport & logistics | 2022 |
| SE14 Taxi Rentals Ltd | Transport & logistics | 2023 |
| SE15 Taxi Rentals Ltd | Transport & logistics | 2023 |
| SE2 Taxi Rentals Ltd. | Transport & logistics | 2016 |
| SE3 Taxi Rentals Ltd. | Transport & logistics | 2016 |
| SE4 Taxi Rentals Ltd. | Transport & logistics | 2016 |
| SE5 Taxi Rentals Ltd. | Transport & logistics | 2016 |
| SE6 Taxi Rentals Ltd. | Transport & logistics | 2016 |
| SE7 Taxi Rentals Ltd | Transport & logistics | 2022 |
| SE8 Taxi Rentals Ltd | Transport & logistics | 2022 |
| SE9 Taxi Rentals Ltd | Transport & logistics | 2022 |
| Search IT Limited | Information & communication | 1992 |
| Searchitlocal Ltd | Professional & scientific | 2010 |
| Searchlight Network Limited | Real estate | 2007 |
| Seasonmaster Air Conditioning Limited | Energy | 2012 |
| Seasons Property Investments Limited | Construction | 2013 |
| Seasons Property Management Limited | Real estate | 2009 |
| Sebastian Graphic Designer Limited | Information & communication | 2014 |
| Secrep Holdings Limited | Financial services | 2019 |
| Secrep Limited | Information & communication | 2019 |
| SECUK1 Limited | Professional & scientific | 2022 |
| Secure Hand Consulting Limited | Information & communication | 2019 |
| Secured Projects Limited | Professional & scientific | 2018 |
| Securerng Limited | Information & communication | 2026 |
| Securink Limited | Administrative & support | 2015 |
| SEE More Clearly AI Solutions Limited | Information & communication | 2026 |
| Seed and Fresh Limited | Wholesale & retail | 2017 |
| Seek Properties Ltd | Real estate | 2022 |
| Seen Social Media Limited | Professional & scientific | 2024 |
| Segas Heating Services Ltd | Construction | 2004 |
| SEK Engineering Limited | Professional & scientific | 2013 |
| Selcouth Holdings Limited | Real estate | 2024 |
| Select Capital Ltd | Administrative & support | 2016 |
| Select Electrical Services (London) Ltd | Administrative & support | 2019 |
| Select Financial Ltd | Administrative & support | 2013 |
| Select Global Learning Limited | Education | 2009 |
| Select Leasing Ltd | Administrative & support | 2016 |
| Select Physio Ltd | Administrative & support | 2014 |
| Select Physiotherapy Limited | Administrative & support | 2006 |
| Select Residential Ltd | Real estate | 2017 |
| Selective Cleaning Company Limited | Other services | 2019 |
| Selins Kebab Ltd | Hospitality | 2026 |
| Selkent Ambulance Service Limited | Administrative & support | 2008 |
| Sema Rentals Limited | Real estate | 2026 |
| Semicolon Systems Ltd | Administrative & support | 2024 |
| Sena Supplies Limited | Wholesale & retail | 2026 |
| Senka Projects Limited | Administrative & support | 2017 |
| Sensible Risk Management Limited | Financial services | 2020 |
| Sentinel Software Systems Limited | Information & communication | 2021 |
| Sequential Sales Limited | Professional & scientific | 2025 |
| Serc Ltd | Construction | 2024 |
| Setpoint Cad-Cam Services Ltd | Professional & scientific | 2012 |
| Seva Community CIC | Other services | 2022 |
| Seven Stars Public House LLP | | 2013 |
| Sevenfour Holdings Ltd | Professional & scientific | 2022 |
| Sevenoaks Scaffolding Ltd | Construction | 2024 |
| Sezer Catering Ltd | Hospitality | 2020 |
| SG Groundworks and Civils Limited | Construction | 2023 |
| SG Team Construction Ltd | Construction | 2022 |
| SG Web Craft Ltd | Information & communication | 2017 |
| SGB Graphic Limited | Administrative & support | 2018 |
| Shah Jalal Construction Limited | Construction | 2018 |
| Shahab Houses Ltd | Real estate | 2021 |
| Shalwin Broadway Ltd | Real estate | 2024 |
| Shalwin GD Wealth Ltd | Financial services | 2026 |
| Shalwin Healthcare Services Limited | Health & social care | 2013 |
| Shalwin Investment Ltd | Real estate | 2011 |
| Shalwin London Ltd | Construction | 2025 |
| Shalwin Organization Limited | Real estate | 2019 |
| Shalwin Sun Real Estate Ltd | Real estate | 2018 |
| Shamos Enterprises Limited | Health & social care | 2016 |
| Shannon Consultancy Limited | Construction | 2019 |
| Shaolin Skateboards Limited | Information & communication | 2018 |
| Shared Support Limited | Health & social care | 2019 |
| SHE Property Services Ltd | Real estate | 2022 |
| Shed Studios Limited | Hospitality | 2025 |
| Sheet Metal Solutions Limited | Manufacturing | 2014 |
| Shelbyline Ltd | Construction | 2016 |
| Shelley Power Literary Agency Limited | Administrative & support | 1984 |
| Shellstream Limited | Hospitality | 2026 |
| Shenfield Services Limited | Construction | 2014 |
| Sherwood Park Primary School | Education | 2013 |
| Shi-Ci Ltd | Hospitality | 2012 |
| Shield Consulting Ltd | Professional & scientific | 2024 |
| Shield Membranes Limited | Administrative & support | 2014 |
| Shifa Tech Services Ltd | Information & communication | 2023 |
| Shift Culture Limited | Professional & scientific | 2026 |
| Shilone Management Ltd | Real estate | 2019 |
| Shire Horse Carriages Limited | Transport & logistics | 2018 |
| Shocare Service Ltd | Health & social care | 2015 |
| Shop IT. Ship IT Ltd | Wholesale & retail | 2024 |
| Shouldersports Ltd | Health & social care | 2015 |
| Show OFF (Blackfen) Limited | Other services | 2016 |
| Showtime Future Stars Limited | Arts & recreation | 2025 |
| Shutford Construction Limited | Construction | 2017 |