| Shakuran Limited | Public administration | 2025 |
| Sharewood Pezzeria Ltd | Hospitality | 2022 |
| Shas Homes Ltd | Construction | 2019 |
| Shekinah Supreme Ltd | Professional & scientific | 2010 |
| Shell Technology Ltd | Information & communication | 2016 |
| Shimmer Nail & Beauty Ltd | Other services | 2026 |
| Shower Curtain Kicker Limited | Wholesale & retail | 2024 |
| Shree Software Solutions PVT Ltd | Information & communication | 2016 |
| Shum's Holding Ltd | Financial services | 2022 |
| Sibfa Investments Ltd | Real estate | 2017 |
| Siddhivinayak Real Estates Limited | Real estate | 2024 |
| Sifa Investments Ltd | Real estate | 2017 |
| Signature Homes Developments Limited | Construction | 2011 |
| Signature Homes Limited | Construction | 2005 |
| Signature Homes MCO Investments Ltd | Real estate | 2020 |
| Signature Homes Painting & Decorating Limited | Construction | 2013 |
| Sikabeba Limited | Transport & logistics | 2022 |
| Silver Sky Estates Limited | Real estate | 2017 |
| Simbox Golf Limited | Wholesale & retail | 2026 |
| Simply Delicious Limited | Hospitality | 2023 |
| Simply Java Coffee Lounge Limited | Hospitality | 2017 |
| Sine Post Ltd | Information & communication | 2012 |
| Sing Along Limited | Health & social care | 2009 |
| Singapore Catering Ltd | Hospitality | 2012 |
| Singapore Orchid Ltd | Hospitality | 2021 |
| Sisken Solutions Ltd | Construction | 2014 |
| SJ Visuals Ltd | Information & communication | 2025 |
| SJD Services London Ltd | Information & communication | 2015 |
| SJT Property Solutions Ltd | Real estate | 2025 |
| SK Advance Hygienist Ltd | Health & social care | 2026 |
| Skin LAB Surrey Ltd | Health & social care | 2020 |
| SL Properties Ltd | Real estate | 2020 |
| SLM Academy Ltd | Education | 2025 |
| SM Jafry Services Ltd | Health & social care | 2022 |
| Smart Accounting London Ltd | Professional & scientific | 2021 |
| Smart Air Mechanical Services Limited | Energy | 2023 |
| Smart and Cozy Homes Ltd | Financial services | 2023 |
| Smiling Beauty Limited | Other services | 2019 |
| SMJ Kitchen Ltd | Hospitality | 2025 |
| SN Energy Consultants Limited | Professional & scientific | 2023 |
| Snaffle Solutions Ltd | Wholesale & retail | 2016 |
| Snatchi Ltd | Administrative & support | 2025 |
| SNC Engineering Ltd | Professional & scientific | 2024 |
| Snookerfans.Co.Uk Ltd | Information & communication | 2019 |
| Snow Bright Ltd | Hospitality | 2011 |
| Snpc Consulting Limited | Professional & scientific | 2025 |
| Soaring Minds Coaching Ltd | Education | 2024 |
| Softfusion Limited | Information & communication | 2000 |
| Soggee Cleaning Services Ltd | Administrative & support | 2025 |
| Soho Media Club Limited | Other services | 2022 |
| Sojmark Limited | Professional & scientific | 2012 |
| SON Media Ltd | Professional & scientific | 2024 |
| Sonavu Ltd | Health & social care | 2026 |
| Sorania Ltd | Construction | 2024 |
| Sorc Van Hire Limited | Administrative & support | 2025 |
| Soundray Medical Ltd | Manufacturing | 2024 |
| Sounds Good Radio Communications Limited | Other services | 1997 |
| South London & Surrey Fencing Ltd | Construction | 2025 |
| Southern Garden Landscaping Ltd | Administrative & support | 2023 |
| Southern Garden Maintenance Ltd | Administrative & support | 2022 |
| Southern Office Supplies Ltd | Administrative & support | 2014 |
| Southldn Cars Ltd | Wholesale & retail | 2025 |
| Southside Property Services Limited | Construction | 2010 |
| Spartan Motorsports & Engineering Ltd | Wholesale & retail | 2025 |
| SPC Plumbing and Heating Limited | Construction | 2007 |
| Spmu Training Ltd | Other services | 2023 |
| Sporting Chances Creative Limited | Education | 2018 |
| SPR Agency Limited | Professional & scientific | 2024 |
| Spwb Ltd | Health & social care | 2026 |
| Square Foot Design Ltd | Professional & scientific | 2001 |
| SR Commercial Cleaning Services Ltd | Other services | 2016 |
| SR Squared Consulting Ltd | Professional & scientific | 2026 |
| SRC Design and Build Limited | Construction | 2012 |
| SRT Heating and GAS Limited | Manufacturing | 2015 |
| SS Incorporated Limited | Information & communication | 2008 |
| Ssaaz Limited | Information & communication | 2025 |
| ST Aidan's Catholic Primary School | Education | 2016 |
| ST Monicas Building Contractors Ltd | Construction | 2022 |
| ST Philopatir Limited | Transport & logistics | 2009 |
| Standout AV Ltd | Manufacturing | 2026 |
| Starbrite Fuel Services Ltd | Wholesale & retail | 2008 |
| Starshot Money Ltd | Information & communication | 2025 |
| Staywithcre Ltd | Construction | 2026 |
| Steak & Shake Ltd | Hospitality | 2016 |
| Steg Services Limited | Professional & scientific | 2021 |
| Steps Ahead Tutoring Ltd | Education | 2021 |
| Steve Allaman Limited | Other services | 2013 |
| Steve's Windows Ltd | Administrative & support | 2011 |
| Stevie Imaging Limited | Health & social care | 2025 |
| Stewart SMC Limited | Information & communication | 2019 |
| Stokoe Ltd | Construction | 2006 |
| Stone Rainbows Limited | Arts & recreation | 2012 |
| Stpg Management Ltd | Real estate | 2021 |
| STR4TEGIC Investments Ltd | Administrative & support | 2021 |
| Stracey Properties Limited | Real estate | 2018 |
| Straithblaine Road Battersea Ltd | Real estate | 2026 |
| Strapped Eliquid Limited | Wholesale & retail | 2017 |
| Strapper Limited | Information & communication | 2015 |
| Stratus Aviation Ltd | Education | 2025 |
| Streamz Audio Visual Ltd | Information & communication | 2020 |