| SR Kent Consultants Limited | Professional & scientific | 2020 |
| SRC Control Systems Ltd | Professional & scientific | 2023 |
| SRC Steel Services Ltd | Construction | 2026 |
| SRH Commercial Ltd | Professional & scientific | 2022 |
| SRI Josh Solutions Ltd | Information & communication | 2015 |
| Sritechnika Ltd | Information & communication | 2014 |
| SRM Holdings (Essex) Ltd | Extraterritorial | 2016 |
| Srmh Holdings Limited | Financial services | 2025 |
| SRP Care Group Ltd | Professional & scientific | 2026 |
| SRP Care Ltd | Health & social care | 2023 |
| SRP Healthcare Ltd | Health & social care | 2022 |
| SRP Homecare Ltd | Health & social care | 2022 |
| SRP Recruitment Ltd | Professional & scientific | 2018 |
| SRP Supported Living Ltd | Health & social care | 2022 |
| SRS (Southampton) LLP | | 2018 |
| SS Interiors & Exteriors Limited | Construction | 2020 |
| SS Portfolio Management Ltd | Professional & scientific | 2025 |
| SS Testmaster Limited | Professional & scientific | 2025 |
| SS9 Developments Ltd | Construction | 2020 |
| SS9 Plastering Ltd | Construction | 2019 |
| SS9 Property Ltd | Real estate | 2020 |
| SS9 Services Limited | Real estate | 2021 |
| Ssjr Consultancy Ltd | Administrative & support | 2013 |
| ST Agnes Taxis Ltd | Transport & logistics | 2025 |
| ST Bathrooms Limited | Construction | 2024 |
| ST Installations Limited | Construction | 2013 |
| ST James Court (Leigh-On-Sea) Freehold Limited | Households | 2018 |
| ST Pierre Services Limited | Construction | 2020 |
| ST Thomas Street (Bristol) LLP | | 2016 |
| ST Trading & Maintenance Ltd | Construction | 2020 |
| ST Vincents Residents Limited | Households | 2014 |
| ST. Michaels School (Leigh-On-Sea) Limited | Education | 1980 |
| Stabilis Associates Ltd | Administrative & support | 2009 |
| Stadia Design Ltd | Professional & scientific | 2023 |
| Staffwise Global Limited | Information & communication | 2023 |
| Stag Solutions (Essex) Limited | Construction | 2025 |
| STAGE1 Developments Ltd | Construction | 2017 |
| Staging ETC Ltd | Administrative & support | 2024 |
| Stallard Holdings Limited | Financial services | 2019 |
| Stalwart Design Services Limited | Professional & scientific | 2020 |
| Staminier Limited | Administrative & support | 2017 |
| Stanford Wellbeing Limited | Health & social care | 2020 |
| Staniel CAY Properties Ltd | Real estate | 2019 |
| Stannard Property Investments Limited | Real estate | 2025 |
| Stapleford Developments Ltd | Real estate | 2024 |
| Stapleford Farm Limited | Construction | 2018 |
| Stapleford Investments Limited | Real estate | 2019 |
| Stareevee Ltd | Extraterritorial | 2021 |
| Starflare Solutions Ltd | Administrative & support | 2023 |
| Starmer Ltd | Manufacturing | 2002 |
| Startec Solutions Ltd | Professional & scientific | 2011 |
| Station Barberz Ltd | Other services | 2021 |
| Stay Location Properties Ltd | Real estate | 2024 |
| Stay Location Property Management Limited | Real estate | 2025 |
| Steel Arts (UK) Limited | Administrative & support | 2008 |
| Steel Arts Ltd | Extraterritorial | 2002 |
| Steel Arts Metalwork Ltd | Manufacturing | 2010 |
| Steel Stream Traders Ltd | Wholesale & retail | 2024 |
| Steelpower Ltd | Wholesale & retail | 2023 |
| Steephill Homes Limited | Real estate | 2016 |
| Steer Road Safety Training Ltd | Education | 2026 |
| Stefan Bertschi Ltd | Professional & scientific | 2024 |
| Stemology Academy Ltd | Education | 2024 |
| Stephen Homes Consultancy Ltd | Professional & scientific | 2024 |
| Stephen John Taylor Electrical Limited | Construction | 2014 |
| Stephen Moreton Limited | Education | 2026 |
| Stephenson Holdings Ltd | Real estate | 2024 |
| Steve Camps Film Ltd | Information & communication | 2024 |
| Steve Jackson Design Limited | Professional & scientific | 2002 |
| Steve Leigh Limited | Professional & scientific | 2016 |
| Steveweld Limited | Wholesale & retail | 1975 |
| Stewards ELM Management Company Limited | Households | 2024 |
| Stewart House Leigh Limited | Households | 2025 |
| Stewart James Designs Ltd | Construction | 2023 |
| Stickings Holdings Limited | Financial services | 2026 |
| Stifford Forge and Engineering Co. Limited | Other services | 1961 |
| Sting & Co. Property Group Limited | Real estate | 2025 |
| Stir Futures Ltd | Financial services | 2022 |
| STJ Properties Group Ltd | Real estate | 2022 |
| Stoburt Ltd | Transport & logistics | 2014 |
| Stock Homes Limited | Construction | 2012 |
| Stock Road MOT & Servicing Limited | Wholesale & retail | 2011 |
| Stockvale Catering Limited | Hospitality | 2012 |
| Stockvale Investments Limited | Financial services | 2008 |
| Stockvale Limited | Arts & recreation | 1976 |
| Stockvale Properties Limited | Construction | 2013 |
| Stockvale Restaurants Limited | Hospitality | 2008 |
| Stoke ASH Ltd | Construction | 2019 |
| Stone Commercial Holdings Ltd | Real estate | 2025 |
| Stone Installations Limited | Construction | 2018 |
| Stone ME Holdings Limited | Professional & scientific | 2018 |
| Stone ME Limited | Professional & scientific | 2003 |
| Stone Worktop Services Limited | Construction | 2017 |
| Stonebridge Hill Ltd | Real estate | 2026 |
| Stonebridge Marketing Ltd | Information & communication | 2026 |
| Storm Creative Media Limited | Information & communication | 2008 |
| Storm Property Rentals Ltd | Real estate | 2025 |
| Stormstone Holdings Limited | Financial services | 2025 |
| Stornoway Road 1970 Limited | Extraterritorial | 2014 |
| Story London Ltd | Other services | 2020 |