| Superior Ceilings and Partitions Ltd | Construction | 2010 |
| Superior Lifts Ltd | Professional & scientific | 2021 |
| Superior Trading and Investing Ltd | Administrative & support | 2022 |
| Superwash (Sidcup) Limited | Other services | 2017 |
| Surbiton Beauty Parlour Ltd | Other services | 2023 |
| Surge Technical Services Limited | Professional & scientific | 2024 |
| Surrey Gardens Limited | Administrative & support | 2016 |
| Survive Plus Limited | Information & communication | 2025 |
| Susan Clark Interiors Limited | Construction | 2015 |
| Susan Miles Limited | Real estate | 2017 |
| Sushi & Bento Ltd | Hospitality | 2023 |
| Sussex Highway Solutions Limited | Construction | 2026 |
| Sustaining Freddy Ltd | Professional & scientific | 2018 |
| Sutton Home Improvements Limited | Construction | 1990 |
| Swallow Lifts Installations Limited | Other services | 1996 |
| Swallow Lifts Limited | Other services | 1998 |
| Swallow Lifts Platforms Limited | Real estate | 2009 |
| Swam Electrical Limited | Construction | 2015 |
| Swanley Tyres Limited | Wholesale & retail | 2015 |
| Swaters Services Limited | Professional & scientific | 2024 |
| Sweet BEA Occasions Ltd | Administrative & support | 2019 |
| Swift Electrical Services (Kent) Limited | Administrative & support | 2009 |
| Swiftly Shutters Limited | Administrative & support | 2017 |
| Swim Stars Kent Limited | Education | 2023 |
| Switchgear Installation and Maintenance Services Ltd | Construction | 2024 |
| Swordteam Limited | | 1978 |
| SXS Consulting Limited | Professional & scientific | 2021 |
| SXS Group Limited | Construction | 2024 |
| SXS Holdings Limited | Households | 2011 |
| SY Yoruk Limited | Hospitality | 2008 |
| Syanco Limited | Professional & scientific | 2005 |
| Sydenham Hill Ltd | Construction | 2017 |
| SYE Healthcare Limited | Health & social care | 2021 |
| Sylvia Chew Associates Limited | Administrative & support | 2016 |
| Sylvia Matthews Bridals Ltd | Wholesale & retail | 2021 |
| Symmetric Wave Limited | Information & communication | 2014 |
| Sympathy 4 U Limited | Other services | 2023 |
| Szgd Consulting Ltd | Professional & scientific | 2025 |
| T & C Final Journey Support Limited | Other services | 2025 |
| T & C Packaging Limited | Administrative & support | 2025 |
| T & J Tiling Ltd | Construction | 2018 |
| T & M Electrical Services Ltd | Construction | 2016 |
| T & T Nails 1 Ltd | Other services | 2023 |
| T & T Property Developers Ltd | Real estate | 2017 |
| T & T Retailers Ltd | Wholesale & retail | 2020 |
| T and K Hvac Ltd | Construction | 2018 |
| T G Motorsport Ltd | Manufacturing | 2015 |
| T Kitto Limited | Administrative & support | 2017 |
| T L Cherry Limited | Health & social care | 2013 |
| T Love Limited | Wholesale & retail | 2016 |
| T Redmond Property Company Limited | Financial services | 2025 |
| T S Electrical (London) Ltd | Administrative & support | 2022 |
| T Shape Limited | Professional & scientific | 2023 |
| T W Administration Solutions Ltd | Real estate | 2009 |
| T&G 2 Services Limited | Administrative & support | 2026 |
| T&G Property Management Limited | Construction | 2014 |
| T&G Services Ltd | Administrative & support | 2022 |
| T&X Services Ltd | Administrative & support | 2025 |
| T. Cradduck Limited | Construction | 2015 |
| T.A. Hellberg Limited | Professional & scientific | 2015 |
| T.Chambers Electrical Services Ltd | Construction | 2020 |
| T.P. Garden Services Ltd | Administrative & support | 2019 |
| T.Roberts & L.Roberts Ltd | Administrative & support | 2009 |
| T2 Electrical Services Ltd | Construction | 2024 |
| Tadworth Investment Holdings Limited | Financial services | 2021 |
| Tadworth Property Limited | Construction | 2014 |
| TAE Studio Ltd | Professional & scientific | 2023 |
| Taelsa Logistics Ltd | Administrative & support | 2025 |
| TAG Hair Limited | Other services | 2012 |
| TAG Media Logistics Ltd | Transport & logistics | 2014 |
| Tagg Installations Ltd | Construction | 2012 |
| Take a Byte Limited | Information & communication | 1992 |
| Take Care Creative Limited | Information & communication | 2026 |
| Takucare Limited | Health & social care | 2024 |
| Takyiwaa Ventures Ltd | Information & communication | 2016 |
| Talented Operations Limited | Professional & scientific | 2023 |
| Talenthub Global Ltd | Information & communication | 2025 |
| Talisman Insurance Broking Limited | Financial services | 2013 |
| Talk to the Hand Limited | Professional & scientific | 2019 |
| Talklogic Systems Ltd | Information & communication | 2016 |
| Talktech Limited | Administrative & support | 2018 |
| Talktotoby Ltd | Administrative & support | 2024 |
| Tangerine Portfolio Ltd | Real estate | 2016 |
| Tanhan Properties Ltd | Real estate | 2022 |
| Tanofix Ltd | Other services | 2023 |
| Tapa Republic (Bexley) Limited | Wholesale & retail | 2025 |
| Tapa Republic (Bluewater) Limited | Wholesale & retail | 2025 |
| Tapa Republic (Leadenhall) Limited | Wholesale & retail | 2025 |
| Tapa Republic (Sidcup) Limited | Wholesale & retail | 2025 |
| Tapa Republic (Westfield London) Limited | Wholesale & retail | 2025 |
| Tapas (Bexley) Ltd | Hospitality | 2025 |
| Tapas (Bluewater) Ltd | Hospitality | 2025 |
| Tapas (Leadenhall) Ltd | Hospitality | 2025 |
| Tapas (Mill ROW) Ltd | Hospitality | 2026 |
| Tapas (Sidcup) Ltd | Hospitality | 2025 |
| Tapas (Westfield) Ltd | Hospitality | 2025 |
| Tapas Bidco Limited | Hospitality | 2023 |
| Tapserve Limited | Transport & logistics | 2026 |
| Tardis Group London Limited | Administrative & support | 2005 |
| Tardis Holdings International Limited | Professional & scientific | 2007 |