| Srln Ltd | Real estate | 2023 |
| SRM Wealth Ltd | Financial services | 2023 |
| SRP (Cambridge) Limited | Real estate | 2023 |
| SRS Task Limited | Construction | 2017 |
| SS & SO Investments Limited | Real estate | 2022 |
| SS Foods Centre Limited | Wholesale & retail | 2025 |
| SSC Space UK Limited | Other services | 2018 |
| SSG Strategy & Innovation Ltd | Professional & scientific | 2026 |
| Ssig UK Limited | Financial services | 2021 |
| SSR Executive Travel Ltd | Transport & logistics | 2015 |
| SSS Care Services Ltd | Health & social care | 2026 |
| ST Albrights Freehold Acquisition Ltd | Households | 2014 |
| ST Andrew's Centre Cafe Limited | Hospitality | 2013 |
| ST Andrew's Park (NO.2) Management Limited | Households | 1995 |
| ST Andrew's Road Garage Limited | Wholesale & retail | 2012 |
| ST Andrews Park (Phase 3C Uxbridge) Management Company Limited | Households | 2018 |
| ST Andrews Park 2B/3A (Churchill Road, Uxbridge) Management Company Limited | Households | 2015 |
| ST Augustine Management Company Limited | Households | 2022 |
| ST Barnabas Ventures Limited | Real estate | 2015 |
| ST Bede's Inter Church School | Education | 2012 |
| ST Catharine's College Development Limited | Construction | 2008 |
| ST Catharine's College Events Limited | Construction | 2008 |
| ST Columba Foundation | Health & social care | 2010 |
| ST Edmund's College Cambridge | Extraterritorial | 1898 |
| ST George's Court Residents' Society Limited | Real estate | 1997 |
| ST Ives Chamber of Commerce Limited | Professional & scientific | 2005 |
| ST Ives Heating & Plumbing Limited | Construction | 2025 |
| ST Ives Scaffolding Hire Limited | Construction | 2025 |
| ST James Quay (Norwich) Residents Management Company Limited | Households | 2021 |
| ST John's College School, Cambridge | Education | 2021 |
| ST John's Enterprises Limited | Hospitality | 1994 |
| ST Just Housing Limited | Real estate | 2014 |
| ST Leonard's (Sudbury) Management Company Limited | Households | 2018 |
| ST Mary's Junior School Limited | Education | 1987 |
| ST Mary's School Cambridge International Limited | Education | 2020 |
| ST Matthew's Place (Cambridge) Management Company Limited | Other services | 2010 |
| ST Michael's School Limited | Education | 1979 |
| ST Neots Chamber of Commerce Limited | Professional & scientific | 2005 |
| ST Neots Road Management Company Limited | Households | 2016 |
| ST Radegund Group Ltd | Hospitality | 2024 |
| ST Refrigeration Ltd | Administrative & support | 2021 |
| ST Renovations and Building Ltd | Construction | 2025 |
| ST Rumbolds Fields Management Company Limited | Households | 2019 |
| ST Thomas Education Group Ltd | Education | 2025 |
| ST. Albrights (Stanway) Management Company Limited | Households | 2011 |
| ST. Barnabas Road Management Ltd | Households | 2011 |
| ST. John's Innovation Centre Limited | Real estate | 1985 |
| St.Anthony Padova Ltd | Wholesale & retail | 2019 |
| St.Ives Windings Limited | | 1968 |
| St.Neots BP Garage Limited | Wholesale & retail | 2020 |
| STA Catering Limited | Hospitality | 2012 |
| STA Consulting Limited | Professional & scientific | 2023 |
| Stable Car Sales Limited | Wholesale & retail | 1983 |
| Stable Trading Limited | Wholesale & retail | 1991 |
| Stable Yard Lode FEN Management Company Limited | Households | 2025 |
| Stabo Limited | Manufacturing | 2007 |
| Stac Cambridge Limited | Real estate | 2018 |
| Stack Yard Court Management Company Limited | Real estate | 2009 |
| Stacnet Ltd | Manufacturing | 2021 |
| Stadard Davici Circle Martech Limited | Information & communication | 2022 |
| Staff Pulse Ltd | Professional & scientific | 2023 |
| STAFF4U Staffing Solutions Ltd | Administrative & support | 2025 |
| Staffhubair Ltd | Manufacturing | 2026 |
| Stafford House Companies Limited | Financial services | 2007 |
| Stafford House School of English Limited | Education | 1960 |
| Stafford House Study Holidays Limited | Education | 1989 |
| Stafford Legal Engineering Limited | Information & communication | 2019 |
| Staffords Accountants Limited | Professional & scientific | 2012 |
| Stage One Interiors Ltd | Professional & scientific | 2019 |
| Staggs Farm (Great Dunmow) Management Company Limited | Households | 2026 |
| Stagsholt Limited | Financial services | 2020 |
| Stallan Close Management Company Limited | Households | 2021 |
| Stallan Properties Limited | Real estate | 2024 |
| Stallions Strategies Ltd | Wholesale & retail | 2025 |
| Stallions Trade Services Ltd | Wholesale & retail | 2019 |
| Stamelos Service Ltd | Manufacturing | 2026 |
| Stamford Chamber of Commerce Limited | Professional & scientific | 2014 |
| Stamford Drake Consultants Ltd | Professional & scientific | 2021 |
| Stamford Park Homes Ltd | Hospitality | 2016 |
| Stamford Publications Limited | Real estate | 1966 |
| Stan Daniel SMW Ltd | Manufacturing | 2023 |
| Stanaero Ltd | Manufacturing | 2026 |
| Stanbourne Property Limited | Real estate | 2025 |
| Stanes Rand Limited | Professional & scientific | 2025 |
| Stanfield Innovations Limited | Professional & scientific | 2026 |
| Stanfield Law Limited | Professional & scientific | 2026 |
| Stanford`S Jeweller`S Ltd | Wholesale & retail | 2008 |
| STANGROUP723 Ltd | Transport & logistics | 2025 |
| Stanhoe & Co | Financial services | 2022 |
| Stanislava Zhivkova Ltd | Manufacturing | 2024 |
| Stansted House Investments Limited | Real estate | 2016 |
| Stantex Co., Ltd | Extraterritorial | 2013 |
| Stanton Square Management Company Limited | Households | 2000 |
| Stapleford Barbers Ltd | Other services | 2023 |
| Stapleford DBA Limited | Extraterritorial | 2023 |
| Stapleford Granary Limited | Hospitality | 2021 |
| Star Colour Laboratories Limited | Extraterritorial | 2016 |
| Star Creation UK Co., Limited | Wholesale & retail | 2023 |
| Star Estate Services Ltd | Households | 2018 |
| Star Living Properties Limited | Real estate | 2022 |