| Sanchi Sisters Ltd | Wholesale & retail | 2025 |
| Sanctuary Medics Limited | Public administration | 2019 |
| Sandel&V Ltd | Construction | 2019 |
| Sanderson Cleaning Service Limited | Administrative & support | 2014 |
| Sandmoore Holdings Limited | Construction | 2025 |
| Sandpiper (London) Limited | Construction | 2000 |
| Sandri Transport Ltd | Transport & logistics | 2023 |
| Sang Saka Ltd | Hospitality | 2025 |
| Sangra Transport Limited | Transport & logistics | 2022 |
| Sanju Properties Ltd | Real estate | 2020 |
| Santi & Santi Holdings Limited | Other services | 2013 |
| Santi & Santi Limited | Hospitality | 2009 |
| Sapphire Court 1 Limited | Real estate | 2023 |
| Sapphire Court 2 Limited | Real estate | 2023 |
| Sapphire Court 3 Limited | Real estate | 2024 |
| Sarelis Estates Limited | Real estate | 2018 |
| Sarl Giorgia Limited | Professional & scientific | 2024 |
| Sarnaptra Properties Limited | Real estate | 2026 |
| Sarp One Ltd | Health & social care | 2015 |
| Sarre AVE Limited | Real estate | 2025 |
| SAS IT Consulting Services Limited | Administrative & support | 2014 |
| SAS Special Projects Limited | Construction | 2009 |
| Sassy Supplements Limited | Wholesale & retail | 2026 |
| Sastroses Ltd | Professional & scientific | 2022 |
| Satinder & Mundeep Ltd | Real estate | 2018 |
| Satnam Natural Limited | Manufacturing | 2026 |
| Satour Builds Ltd | Construction | 2020 |
| Satyam Enterprises Limited | Real estate | 2011 |
| Savannah Services (UK) Ltd | Other services | 1997 |
| Save South Leatherhead Ltd | Other services | 2013 |
| Saviour Apprl Ltd | Other services | 2021 |
| Saxonchart Limited | Construction | 2007 |
| SAY Less Holdings Ltd | Financial services | 2026 |
| Sayaa Grill Ltd | Hospitality | 2020 |
| SB & PK Limited | Hospitality | 2025 |
| SBG Estates Ltd | Financial services | 2025 |
| SBL Ideas Ltd | Administrative & support | 2017 |
| SBL Scaffolding Limited | Construction | 2018 |
| SBR Partners Limited | Information & communication | 2000 |
| Scale Group Holdings Limited | Financial services | 2024 |
| Scalexcel Ltd | Information & communication | 2024 |
| Scam Awareness & Fraud Education CIC | Education | 2025 |
| Scan Data Experts Limited | Administrative & support | 2011 |
| Schaf Invest Ltd | Real estate | 2013 |
| Schengen Office (London) Limited | Administrative & support | 2009 |
| Schmooboo & Co. Ltd | Professional & scientific | 2018 |
| School of Excellence Ltd | Education | 2021 |
| Sciad Ltd | Professional & scientific | 2007 |
| SCL Solutions Limited | Wholesale & retail | 2001 |
| SCM ADV Limited | Professional & scientific | 2025 |
| SCM Capital Limited | Real estate | 2021 |
| SCM E6 Ltd | Real estate | 2025 |
| Scott & Partners Ltd | Administrative & support | 2026 |
| Scott Financial Services Ltd | Financial services | 2020 |
| Scottman Group Limited | Wholesale & retail | 2025 |
| Scottman UK Limited | Wholesale & retail | 2025 |
| Scottmen Limited | Wholesale & retail | 2025 |
| Scuderia Reemax Ltd | Information & communication | 2009 |
| SD Pro Ltd | Public administration | 2017 |
| SDF Consultants Limited | Professional & scientific | 2021 |
| SDG General Trading Ltd | Manufacturing | 2018 |
| SDN Pro Services Ltd | Construction | 2026 |
| Sea the Pearls Ltd | Hospitality | 2024 |
| Sea Wolf Ltd | Real estate | 2023 |
| Sean Mackenzie Film Editing Ltd | Information & communication | 2012 |
| Seas Properties Ltd | Real estate | 2021 |
| Seasonvale Limited | Construction | 2004 |
| Seat VIP Ltd | Transport & logistics | 2025 |
| Seaways Apartment Limited | Real estate | 2022 |
| Seaways Property Ltd | Real estate | 2020 |
| Sebb Associates Limited | Financial services | 2023 |
| Secarch Limited | Professional & scientific | 2011 |
| Second FIX Depot Ltd | Wholesale & retail | 2023 |
| Secret Move Ltd | Administrative & support | 2022 |
| Secret Shoes Ltd | Wholesale & retail | 2025 |
| Secure Alliance Ltd | Other services | 2021 |
| Securitech Recruitment Services Limited | Administrative & support | 2016 |
| SEE Green BL Ltd | Financial services | 2024 |
| SEE Green Contractors LLP | | 2016 |
| SEE Green Properties (Romford) Ltd | Real estate | 2020 |
| SEE Green Properties Limited | Administrative & support | 2016 |
| SEE Green TIA Ltd | Financial services | 2024 |
| Seedwell Limited | Construction | 2004 |
| SEF London Ltd | Hospitality | 2019 |
| Sefnetix UK Ltd | Wholesale & retail | 2020 |
| Segal Business Ltd | Other services | 2011 |
| Sekhon Investments Limited | Real estate | 2011 |
| Selasi Studio Limited | Wholesale & retail | 2021 |
| Selvashine Ltd | Real estate | 2023 |
| SEM Renovation Ltd | Construction | 2022 |
| SEN Manny Mentor Ltd | Professional & scientific | 2025 |
| Senel 71 Ltd | Hospitality | 2019 |
| Senko Construction Ltd | Construction | 2026 |
| Sennik Investments Limited | Financial services | 2017 |
| Sensei Chelle Ltd | Education | 2025 |
| Serendipity Travel Ltd | Administrative & support | 2012 |
| Serhio and Co Ltd | Construction | 2017 |
| Service SA Ltd | Hospitality | 2023 |
| Serviced Living Limited | Administrative & support | 2016 |
| SET LDN Ltd | Arts & recreation | 2016 |