| Snackbox Cafe Ltd | Hospitality | 2025 |
| Snacklet Ltd | Wholesale & retail | 2025 |
| SNF Solutions Ltd | Construction | 2025 |
| Snowdrop London Cleaning Services Limited | Administrative & support | 2014 |
| SNOWDROP2020 Ltd | Hospitality | 2022 |
| SNOWDROP2023 Ltd | Hospitality | 2024 |
| Social Interest and Responsibility (SIR) Limited | Information & communication | 2024 |
| Social Magnet Marketing Ltd | Professional & scientific | 2022 |
| Socially Networking Ltd | Professional & scientific | 2025 |
| Sofa-Gazi Ltd | Manufacturing | 2016 |
| Sofia Properties Ltd | Real estate | 2017 |
| Sofia Property Holdings Ltd | Real estate | 2024 |
| Sogut Properties Ltd | Real estate | 2025 |
| Soho Partnership Ltd | Real estate | 2026 |
| Solar Solutions by Steve Limited | Construction | 2026 |
| Solara Enterprises Ltd | Wholesale & retail | 2026 |
| Solomons UK Ltd | Wholesale & retail | 2009 |
| Soma Post Production Limited | Information & communication | 2011 |
| Sombrero Loco Limited | Hospitality | 2020 |
| Soniachi Ltd | Health & social care | 2022 |
| Soulbury Management Company Limited | Households | 1978 |
| Soulscape Shala Ltd | Education | 2022 |
| South Beach Mansions Management Company Limited | Households | 2021 |
| South Cambridgeshire Investment Partnership LLP | | 2020 |
| South Mimms Commercials Limited | Wholesale & retail | 2026 |
| South River Ltd | Hospitality | 2025 |
| Southdown Radio Ltd | Information & communication | 2020 |
| Spanners Tyres & Alignment Centre Ltd | Wholesale & retail | 2024 |
| Spartan FX Limited | Financial services | 2018 |
| Specialist Data Systems Limited | Information & communication | 1997 |
| Specified Contracts Ltd | Administrative & support | 2010 |
| Spectralight Communications Ltd | Information & communication | 2020 |
| Speeders Transport Ltd | Transport & logistics | 2024 |
| Spence Studio Ltd | Manufacturing | 2025 |
| Spick Cars Ltd | Wholesale & retail | 2017 |
| Spicy Chilli Ltd | Hospitality | 2023 |
| Spill the Beans Coffee Box Limited | Manufacturing | 2025 |
| Spoken Word Ministries Limited | Other services | 2013 |
| Sports Calendars Limited | Professional & scientific | 2009 |
| Sports Connoisseur Management Ltd | Other services | 2017 |
| Spotless Building Services Ltd | Administrative & support | 2019 |
| Sprintboxx Ltd | Energy | 2024 |
| Spyrou Medical Ltd | Health & social care | 2017 |
| SR Consultancy London Ltd | Professional & scientific | 2023 |
| SRC Services Ltd | Arts & recreation | 2025 |
| SRF Asset Investments Ltd | Real estate | 2019 |
| SS Creative Ltd | Professional & scientific | 2011 |
| SS Fixing Group Ltd | Construction | 2024 |
| SS Kebab House Ltd | Hospitality | 2024 |
| SS Prestige Trading Ltd | Professional & scientific | 2025 |
| SSB General Builders Limited | Construction | 2025 |
| SSK Property Development Ltd Ltd | Real estate | 2025 |
| ST Albans Home Group Ltd | Real estate | 2026 |
| ST Mary's Court RTM Company Limited | Households | 2023 |
| Stacey Road (North) Freehold Limited | Households | 2021 |
| Stacey Road (South) Freehold Limited | Households | 2021 |
| Stack Property Management Ltd | Professional & scientific | 2024 |
| Stainless Welding & Fabrication Limited | Manufacturing | 2004 |
| Stakz Clothing Limited | Other services | 2024 |
| Stalbridge Kebab Ltd | Hospitality | 2023 |
| Stan Auto Group Limited | Water & waste | 2023 |
| Stanley House Residents Association Limited | Households | 1982 |
| Stanton Design Ltd | Professional & scientific | 2019 |
| Stanwell Close Ltd | Construction | 2022 |
| Star Design Five Ltd | Information & communication | 2023 |
| Star Design Four Ltd | Information & communication | 2023 |
| Star Design Tech 4 Ltd | Information & communication | 2026 |
| Star Design Tech 6 Ltd | Information & communication | 2024 |
| Star Design Three Ltd | Information & communication | 2023 |
| Star Design Two Ltd | Information & communication | 2023 |
| Star Operations Five Ltd | Information & communication | 2024 |
| Star Operations SIX Ltd | Information & communication | 2024 |
| Star Operations Three Ltd | Information & communication | 2024 |
| Star Operations Two Ltd | Information & communication | 2024 |
| Star Tech Operations Five Ltd | Information & communication | 2026 |
| Star Tech Operations Four Ltd | Information & communication | 2026 |
| Star Tech Operations One Ltd | Information & communication | 2025 |
| Star Tech Operations SIX Ltd | Information & communication | 2026 |
| Star Tech Operations Three Ltd | Information & communication | 2025 |
| Star Tech Operations Two Ltd | Information & communication | 2025 |
| Starbury Developments Ltd | Construction | 2021 |
| Starr Engineering Ltd | Construction | 2026 |
| Steaua 86 Ltd | Transport & logistics | 2016 |
| Steffi's Food Limited | Hospitality | 2026 |
| Steph Storm Ltd | Professional & scientific | 2024 |
| Stephens Holdings Ltd | Real estate | 2020 |
| Sterling Diamond London Ltd | Wholesale & retail | 2024 |
| Steve Smith Limited | Wholesale & retail | 2006 |
| STK Drylining Construction Ltd | Construction | 2025 |
| Stone and BBQ Ltd | Hospitality | 2024 |
| Stoneaxis Living Ltd | Construction | 2025 |
| Stones 4U Limited | Construction | 2012 |
| Stoney Clibbens-Stoney Creative Limited | Professional & scientific | 2011 |
| Stoney Engineering Ltd | Wholesale & retail | 2026 |
| Stotfold Juniors Development Centre Ltd | Education | 2016 |
| Strategy Mortgage Solutions Ltd | Financial services | 2026 |
| Streets Ahead Property Management Limited | Construction | 2017 |
| Streetz Ahead Dance Academy Limited | Arts & recreation | 2014 |
| Stromberg Design Limited | Professional & scientific | 2016 |
| Studio 22 Reformer Pilates Limited | Other services | 2025 |