| SS Athletics Performance Ltd | Arts & recreation | 2023 |
| SS Jamal Food Ltd | Hospitality | 2023 |
| SS7 Ltd | Manufacturing | 2011 |
| SS8 Plumbing Limited | Other services | 2007 |
| Sscp Roasting Limited | Hospitality | 2025 |
| Ssiz Ltd | Hospitality | 2025 |
| Sssg Limited | Administrative & support | 2013 |
| ST Edmunds Butchers and Catering Ltd | Wholesale & retail | 2024 |
| ST Optical Services Limited | Wholesale & retail | 2018 |
| Stacie Kinchin Ltd | Other services | 2010 |
| Stag Flooring Ltd | Construction | 2025 |
| Stan & Ollie Productions Ltd | Information & communication | 2019 |
| Stanford Motel Limited | Hospitality | 2007 |
| Stanford-Le-Hope Builders Merchants Limited | Construction | 1981 |
| Stanfords Jewellery and Repairs Limited | Manufacturing | 2023 |
| Stanway Contracts Limited | Agriculture & fishing | 1957 |
| Star Batteries London Ltd | Wholesale & retail | 2025 |
| Star Batteries Ltd | Wholesale & retail | 2023 |
| Star Buys Group Ltd | Other services | 2024 |
| Star Estates (South East) Ltd | Real estate | 2024 |
| Star Estates Holding Ltd | Financial services | 2025 |
| Star Sports and Soccer Limited | Other services | 2008 |
| Stardigo Ltd | Manufacturing | 2024 |
| Starr Angel Limited | Information & communication | 2023 |
| Stars Take Away Ltd | Hospitality | 2020 |
| Start Point (Essex) Ltd | Construction | 2012 |
| Staszewski Consulting Ltd | Information & communication | 2017 |
| Steadfast Structural Engineering Services Limited | Construction | 1992 |
| Steeple Enterprises Ltd | Administrative & support | 2014 |
| Stellar Education Ltd | Administrative & support | 2016 |
| Stellar Trader Academy Limited | Administrative & support | 2021 |
| Stentpack Limited | Manufacturing | 2012 |
| Stephanie Jane Interiors Ltd | Professional & scientific | 2021 |
| Stephanie Stern Architecture & Interiors Ltd | Extraterritorial | 2023 |
| Stepoutinessex CIC | Health & social care | 2024 |
| Sterling Essence Care Ltd | Health & social care | 2023 |
| Sterling FM Services Limited | Administrative & support | 2025 |
| Sterling Group Consultants Limited | Real estate | 2021 |
| Sterling Homestead CIC | Real estate | 2024 |
| Sterling Homestead Properties Ltd | Real estate | 2024 |
| Sterling Housing | Professional & scientific | 2020 |
| Steve's Radio Cars Limited | Transport & logistics | 2003 |
| Stevens Paving Limited | Construction | 2014 |
| Stewart Bespoke Stairs Limited | Manufacturing | 2026 |
| Stiaca Services Ltd | Professional & scientific | 2020 |
| Stockmyshop Ltd | Wholesale & retail | 2026 |
| Storymakers London Ltd | Professional & scientific | 2023 |
| Stratford Waste Management Ltd | Water & waste | 2025 |
| Strawberry Property Group Ltd | Real estate | 2024 |
| Stray Collective Limited | Wholesale & retail | 2026 |
| Streetscope Limited | Information & communication | 2012 |
| Strongwish Limited | Other services | 2000 |
| Studio 35 Fitness Limited | Arts & recreation | 2018 |
| Studio 35 Franchising Ltd | Arts & recreation | 2023 |
| Studio by BEX Ltd | Other services | 2026 |
| Studio Core Activewear Ltd | Wholesale & retail | 2024 |
| Stygrid Property Developers Limited | Construction | 2004 |
| Sub-Zero Airconditioning Ltd | Energy | 2021 |
| Subscription Collections Ltd | Administrative & support | 2018 |
| Suburban Property Services Ltd | Real estate | 2026 |
| Succinctt Care Limited | Other services | 2022 |
| Sudbury Holdings Limited | Real estate | 2020 |
| Sugarflair Colours Limited | Manufacturing | 2010 |
| Sugarflair Group Limited | Financial services | 2016 |
| Sugarflair UK Limited | Other services | 1982 |
| Sullivan and Rothwell Ltd | Real estate | 2017 |
| Sunflower Dachshund Daycare (and Hotel) Ltd | Other services | 2024 |
| Sunita & SON Limited | Other services | 2014 |
| Sunrise Banqueting Ltd | Hospitality | 2025 |
| Supermoon Digital Ltd | Professional & scientific | 2019 |
| Supermoon Digital Media Ltd | Professional & scientific | 2023 |
| Superprogrammes Limited | Administrative & support | 2013 |
| SUPPLEMENTS4ALL Ltd | Wholesale & retail | 2017 |
| Supreme Shotblasting Limited | Manufacturing | 2024 |
| Sure Wise Limited | Information & communication | 2010 |
| Surrey Opera | Arts & recreation | 1990 |
| SUS Style Limited | Wholesale & retail | 2024 |
| Susegad Solutions Ltd | Professional & scientific | 2025 |
| SW Motor Dealers Ltd | Wholesale & retail | 2023 |
| SW Team Ltd | Administrative & support | 2026 |
| Swan Court (Benfleet) Management Company Limited | Households | 1987 |
| Swifin Capital Ltd | Information & communication | 2019 |
| Swifin Holdings Ltd | Information & communication | 2019 |
| Swifin Platform Ltd | Information & communication | 2019 |
| SY Media Ltd | Information & communication | 2010 |
| Sydney Newton Properties Limited | Real estate | 2021 |
| Sylviasolutions Limited | Professional & scientific | 2025 |
| Symeon Electrical Ltd | Construction | 2017 |
| Symmetri Collective Limited | Wholesale & retail | 2021 |
| Synashe Limited | Health & social care | 2013 |
| Synergy Electrical Ltd | Construction | 2016 |
| T & E Property Holdings Ltd | Real estate | 2026 |
| T a B Project Solutions Limited | Financial services | 2012 |
| T E S Southern Limited | Construction | 2018 |
| T Gull Services Ltd | Wholesale & retail | 2016 |
| T K Newman Ltd | Professional & scientific | 2022 |
| T Sawyer Property Services Limited | Real estate | 2020 |
| T Waller Limited | Construction | 2026 |
| T&M Absolute Property Maintenance Ltd. | Construction | 2021 |
| T&N Demolition Ltd | Construction | 2024 |