| Sheppard Doors & Windows Limited | Construction | 2021 |
| Sheppard Estates Ltd | Real estate | 2022 |
| Shergill Haulage Limited | Transport & logistics | 2014 |
| Shermuc Solutions Ltd | Manufacturing | 2024 |
| Sherwen Engineering Co Limited | Manufacturing | 1986 |
| Sherwood Place (Langton Green) Management Company Limited | Households | 1996 |
| Shetty Mart Limited | Wholesale & retail | 2020 |
| SHF Holdings Trading Ltd | Professional & scientific | 2017 |
| Shicken Foods Ltd | Manufacturing | 2020 |
| Shift Consultants Ltd. | Other services | 2014 |
| Shilo'Z Ltd | Hospitality | 2016 |
| Shimr Investments Limited | Real estate | 2024 |
| Shine Construction Works Ltd | Construction | 2024 |
| Shine Solar Power Limited | Energy | 2023 |
| Shine Space Management (UK) Limited | Real estate | 2019 |
| Shine Time Car Wash Limited | Other services | 2016 |
| Shinetime Window Cleaners Ltd | Administrative & support | 2017 |
| Shire CONSULTANCY9 Limited | Information & communication | 2014 |
| Shire Contract Consultants Ltd | Other services | 2025 |
| Shiv Industries UK Ltd | Transport & logistics | 2022 |
| Shivasai Sudheshna Technologies Limited | Professional & scientific | 2019 |
| Shock Principle Limited | Other services | 2004 |
| Shogreen Holdings Ltd | Real estate | 2025 |
| Sholongoservices Limited | Other services | 2025 |
| Shop and Send Logistics Ltd | Transport & logistics | 2024 |
| SHOP4ALL Limited | Extraterritorial | 2005 |
| Shopfront Services (London) Limited | Construction | 2010 |
| Shopfront Services (Maintenance) Ltd | Construction | 2023 |
| Shopora Europe Limited | Wholesale & retail | 2026 |
| Short LET Consulting Ltd | Real estate | 2012 |
| SHOTBYP90 Ltd | Professional & scientific | 2025 |
| Shoutybear Ltd | Information & communication | 2021 |
| Shower ME Ltd | Manufacturing | 2015 |
| Shred-On-Site Limited | Administrative & support | 2007 |
| Shree JAY Limited | Real estate | 2023 |
| Shree JSN Limited | Wholesale & retail | 2021 |
| Shree SAI Properties Ltd | Real estate | 2015 |
| Shree SAI Trading Ltd | Wholesale & retail | 2011 |
| Shree Trading Limited | Other services | 2017 |
| Shreemsm Limited | Real estate | 2019 |
| Shreysash Limited | Real estate | 2025 |
| Shri Krisshna Ltd | Health & social care | 2019 |
| Shri Sthira Lettings Limited | Real estate | 2026 |
| Shruthi's Kitchen Ltd | Hospitality | 2022 |
| Shshines Ltd | Other services | 2022 |
| Shuangxi Limited | Transport & logistics | 2025 |
| Shubhadra Estate Limited | Real estate | 2025 |
| Shutter Creations Ltd | Manufacturing | 2025 |
| Shuvyoma Bakery Ltd | Wholesale & retail | 2025 |
| SHW Design Ltd | Administrative & support | 2002 |
| Shypka Ltd | Construction | 2025 |
| SIAM24 Ltd | Hospitality | 2022 |
| Siciliana A.R Limited | Other services | 2011 |
| SID Trucking Limited | Transport & logistics | 2018 |
| Siddhi Vinayak Ltd | Health & social care | 2022 |
| Sidecar Management Ltd | Professional & scientific | 2024 |
| Sidly UK Ltd | Wholesale & retail | 2023 |
| Sierra’S Solutions Ltd | Health & social care | 2025 |
| Signaturej Limited | Professional & scientific | 2017 |
| Signet Consultancy Limited | Administrative & support | 2006 |
| Signet Ring Ltd | Real estate | 2024 |
| Signs Direct (Kent) Ltd | Administrative & support | 2016 |
| Siib Ltd | Administrative & support | 2016 |
| Sila Ltd | Hospitality | 2025 |
| Silqmist.Com Ltd | Wholesale & retail | 2021 |
| Silver & Bold Ltd | Health & social care | 2022 |
| Silver Brothers Ltd | Information & communication | 2021 |
| Silver Sapphire Consulting Limited | Professional & scientific | 2008 |
| Silver Screen Subtitling Limited | Information & communication | 2000 |
| Silver Square Ltd | Financial services | 2022 |
| Silverback Creations Ltd | Professional & scientific | 2024 |
| Silverbirch Healthcare Ltd. | Health & social care | 2017 |
| Silverline Management Consultancy Limited | Professional & scientific | 2025 |
| Silverline Mortgages Limited | Financial services | 2025 |
| Silvertown Limited | Construction | 2022 |
| SIM Group Limited | Transport & logistics | 2026 |
| Simba 53 Ltd | Hospitality | 2025 |
| Simex International Ltd | Wholesale & retail | 2016 |
| Simmons Electrical Services Ltd | Construction | 2020 |
| Simon and ZOE Developments Ltd | Real estate | 2022 |
| Simon James Catering Ltd | Hospitality | 2018 |
| Simon James Group Ltd | Wholesale & retail | 2021 |
| Simple Scaffold Designs Limited | Construction | 2013 |
| Simply Bouncy Castle Hire Ltd | Other services | 2016 |
| Simpson Wilson Associates Limited | Professional & scientific | 2016 |
| Singhraj International (UK) Co. Ltd | Real estate | 2022 |
| Sinusoidal Limited | Information & communication | 2012 |
| Siona Limited | Real estate | 2023 |
| SIP and Sando Ltd | Hospitality | 2024 |
| Sira Homes Ltd | Real estate | 2020 |
| Sira Investments Ltd | Real estate | 2020 |
| Sirca Interiors Limited | Construction | 2007 |
| Sirée Aesthetics Ltd | Health & social care | 2020 |
| Sism Square Limited | Wholesale & retail | 2022 |
| Sissons Holdings Limited | Real estate | 2015 |
| Sister SAX Ltd | Arts & recreation | 2025 |
| Sisters Close Bexley Estate Limited | Real estate | 2022 |
| Sitheni Pilani Ltd | Health & social care | 2019 |
| Sivakamasundari Limited | Health & social care | 2026 |
| Sizmic Limited | Wholesale & retail | 2024 |