| Salisbury House Freehold Limited | Households | 2016 |
| Salkaara Ltd | Hospitality | 2026 |
| Sall Residential Ltd | Real estate | 2021 |
| Salloway Accounting & Advisory Ltd | Professional & scientific | 2025 |
| Sals Hot Chicken Ltd | Hospitality | 2025 |
| Salt and Light Estates Ltd | Real estate | 2026 |
| Salters Music Limited | Information & communication | 2016 |
| Salters Properties Ltd | Real estate | 2023 |
| Saltlightluxe Ltd | Wholesale & retail | 2025 |
| Saltwhistle Ltd | Professional & scientific | 2022 |
| Salvatex Collections Limited | Water & waste | 2002 |
| Salvesen Insulated Frames Limited | Construction | 2010 |
| Salvesen Logistics Holdings Limited | Extraterritorial | 1992 |
| Salvesen Logistics Limited | Professional & scientific | 1938 |
| Salvum Limited | Professional & scientific | 2013 |
| Salz Hot Chicken Ltd | Hospitality | 2024 |
| SAM Films Limited | Information & communication | 2010 |
| SAM Gornall Racing Ltd | Arts & recreation | 2026 |
| SAM Imperial Autos Ltd | Wholesale & retail | 2026 |
| SAM Lewis Tiling Ltd | Construction | 2025 |
| SAM Minimart Ltd | Wholesale & retail | 2025 |
| SAM Mortgages Ltd | Financial services | 2023 |
| Sam&Co Ltd | Transport & logistics | 2016 |
| Sam&Daughters Enterprise Limited | Wholesale & retail | 2024 |
| Sam&Jess Courier Ltd | Transport & logistics | 2022 |
| Sam's Hot Chicken Ltd | Hospitality | 2025 |
| Sama Cleaning Services Ltd | Administrative & support | 2025 |
| Sama Group Holdings Limited | Financial services | 2024 |
| Sama Logistics Solution Limited | Wholesale & retail | 2025 |
| Sama Trading Ltd | Other services | 2019 |
| Samad Capital Ltd | Financial services | 2025 |
| Samantha Cameron Social Media Coaching Ltd | Administrative & support | 2020 |
| Samba Tedesco Ltd | Financial services | 2024 |
| Samba Wholesale Ltd | Wholesale & retail | 2024 |
| Sameeha Madeeha Investments Ltd | Real estate | 2022 |
| Samera Contracting Limited | Construction | 2017 |
| Sami's Healthcare Supplies Ltd | Health & social care | 2025 |
| Sammer Ltd | Information & communication | 2018 |
| Sammie Fern Ltd | Public administration | 2020 |
| Sammy a Enterprises Limited | Other services | 2008 |
| Sammy's Socceroos Limited | Education | 2016 |
| Samosa and Sauce Ltd | Hospitality | 2020 |
| Samosa Snack Bar Limited | Hospitality | 2023 |
| Samps Group Limited | Financial services | 2018 |
| Sampurna Foods Ltd | Hospitality | 2025 |
| Samra Realty Ltd | Real estate | 2025 |
| Samrai Associates Limited | Professional & scientific | 2013 |
| Samrunal LLP | | 2021 |
| Samruti Limited | Real estate | 2002 |
| Sams Coffee and Cream Ltd | Hospitality | 2025 |
| Sams Transport Ltd | Transport & logistics | 2026 |
| Samson MD Ltd | Construction | 2026 |
| Samsterdan Property Ltd | Real estate | 2020 |
| Samuel David Properties Limited | Professional & scientific | 2023 |
| Samuel John Construction Ltd | Manufacturing | 2023 |
| Samuel John Properties Ltd | Real estate | 2021 |
| Samuels Christian Nursery | Education | 2004 |
| Samuri Motor Company Limited | Manufacturing | 2018 |
| Samwise Limited | Professional & scientific | 2020 |
| Samy Recovery Ltd | Transport & logistics | 2025 |
| SAN José LLP | | 2023 |
| Sanaa Beauty Studio Ltd | Other services | 2025 |
| Sanaa Holdings Ltd | Wholesale & retail | 2025 |
| Sanabria Autocare Ltd | Wholesale & retail | 2025 |
| Sanctuary Systems (UK) Ltd | Information & communication | 2025 |
| Sand Dams Worldwide Limited | Administrative & support | 2002 |
| Sand Dams Worldwide Trading Limited | Wholesale & retail | 2004 |
| Sandallwood Limited | Wholesale & retail | 1996 |
| Sandalwood & Co UK Ltd | Real estate | 2021 |
| Sanders & Associates Limited | Professional & scientific | 2025 |
| Sanderson Design Limited | Other services | 2021 |
| Sandersons Property Services Ltd | Manufacturing | 2012 |
| Sandko & Co Developments Ltd | Real estate | 2020 |
| Sandko & Co Ltd | Real estate | 2018 |
| Sandro Car Wash Limited | Administrative & support | 2025 |
| Sandton London EC1Y Limited | Administrative & support | 2010 |
| Sandwich Country Caravan Park Ltd | Hospitality | 2024 |
| Sandwich World Ltd | Hospitality | 2019 |
| Sandy Engineering Limited | Professional & scientific | 2015 |
| Sandy Lane Farmers Ltd. | Administrative & support | 2019 |
| Sandy ROY Ltd | Information & communication | 2025 |
| Sandyhill Care Limited | Health & social care | 2026 |
| Sandyy Limited | Public administration | 2022 |
| Sankofa Connect Ltd | Wholesale & retail | 2025 |
| Sankofa Hair Studio Ltd | Other services | 2024 |
| Sannachan Financial Services Ltd | Professional & scientific | 2015 |
| Sano Homes Ltd | Real estate | 2025 |
| Santa Margarita LLP | | 2023 |
| Santab Limited | Wholesale & retail | 2021 |
| Santander Guarantee Company | Extraterritorial | 1992 |
| Santina's Wood Fired Pizza Co Limited | Hospitality | 2021 |
| Sanwar Ltd | Health & social care | 2023 |
| Saoirse Property Management Limited | Real estate | 2023 |
| Saponaria Limited | Manufacturing | 2018 |
| Sapphire Ambulance Service Limited | Transport & logistics | 2025 |
| Sapphire Care Solutions Ltd | Education | 2020 |
| Sapwell Properties Limited | Real estate | 2005 |
| Sara Infotech Limited | Information & communication | 2024 |
| Sara Young & Co Ltd | Professional & scientific | 2012 |
| Sarag ALI Investments Ltd | Real estate | 2024 |