| Shiny Cleaning London Ltd | Administrative & support | 2024 |
| Shiny Marble Granite Ltd | Manufacturing | 2024 |
| Shiproof Limited | Wholesale & retail | 2024 |
| Shipu Hair and Beauty Ltd | Other services | 2026 |
| Shire 1 Letting Ltd | Real estate | 2022 |
| Shiv Building & Construction Services Ltd | Construction | 2025 |
| Shiva Recruitment Ltd | Administrative & support | 2025 |
| SHK Healthcare Service Ltd | Health & social care | 2021 |
| Shobu & Sons Limited | Real estate | 2020 |
| Shodix Ltd | Manufacturing | 2021 |
| Shoe Avenue Ltd | Wholesale & retail | 2025 |
| Shofa Limited | Other services | 2022 |
| Shop 295 Ltd | Wholesale & retail | 2024 |
| Shop Centre Ltd | Wholesale & retail | 2022 |
| Shop Home Limited | Wholesale & retail | 2026 |
| Shop&Restaurant Ltd | Wholesale & retail | 2015 |
| Shopiness Ltd | Wholesale & retail | 2023 |
| Shopiqo Ltd | Wholesale & retail | 2025 |
| Shopivexa Ltd | Wholesale & retail | 2026 |
| Shoppers Hub Ltd | Wholesale & retail | 2026 |
| Shoskie Ltd | Transport & logistics | 2024 |
| Shukran Baklava and Kunefe Ltd | Hospitality | 2026 |
| Shun Cheong Lung Holding Company Limited | Professional & scientific | 2002 |
| Shvets Construction Services Ltd | Construction | 2026 |
| Sicilian Food Suppliers Limited | Wholesale & retail | 2003 |
| Sida Works Ltd | Construction | 2025 |
| Siddam Solutions Ltd | Information & communication | 2024 |
| Siddique Courier Service Ltd | Transport & logistics | 2024 |
| Side-Xuest CIC | Professional & scientific | 2025 |
| Sideroad Films Ltd | Information & communication | 2026 |
| Sidhu Saab Events Ltd | Hospitality | 2023 |
| Sidney Spice Limited | Hospitality | 2025 |
| Siewierski Limited | Construction | 2017 |
| Sigma International Solutions Limited | Wholesale & retail | 2025 |
| Sigma Personnel Ltd | Professional & scientific | 2019 |
| Signage Artistry Limited | Professional & scientific | 2025 |
| Signature Concept by LE PIN Fondu Ltd | Hospitality | 2026 |
| Siibla Ltd | Real estate | 2008 |
| SIL Construction Ltd | Construction | 2024 |
| Siladi Trans Ltd | Transport & logistics | 2018 |
| Silent Shriek Ltd | Information & communication | 2023 |
| Silicore Electronics Ltd | Wholesale & retail | 2019 |
| Silitra Ltd | Construction | 2018 |
| Silk House Hotel Ltd | Hospitality | 2011 |
| Silk Professional Services Limited | Administrative & support | 2010 |
| Silven Ltd | Information & communication | 2011 |
| Silver Community Housing CIC | Hospitality | 2025 |
| Silver Perry Limited | Hospitality | 2025 |
| Silver Stitch Limited | Wholesale & retail | 2024 |
| Silverback Taekwondo CIC | Education | 2026 |
| Silvercart Ltd | Wholesale & retail | 2025 |
| Silverlake Properties Limited | Real estate | 2003 |
| Silverstone Cars Ltd | Wholesale & retail | 2013 |
| Silviu Move & Trans Ltd | Transport & logistics | 2015 |
| Simargl IT Limited | Information & communication | 2024 |
| Simdee IT Ventures Limited | Information & communication | 2021 |
| Simid Consultancy Limited | Health & social care | 2021 |
| Simids Properties Ltd | Real estate | 2026 |
| Simion TEC Solution Ltd | Wholesale & retail | 2026 |
| Simon Martin Plumbing Ltd | Construction | 2026 |
| Simon Sales Limited | Construction | 2019 |
| Simpa Ltd | Construction | 2025 |
| Simple Concept Ltd | Hospitality | 2025 |
| Simple W&W Limited | Wholesale & retail | 2021 |
| Simply Appliances & Furniture Ltd | Manufacturing | 2020 |
| Simply Chicken Ltd | Hospitality | 2021 |
| Simply Energy Solutions Limited | Other services | 2013 |
| Simplyjob Limited | Administrative & support | 2024 |
| Simplymens Trading Ltd | Wholesale & retail | 2020 |
| Simya Luxury Services Ltd | Transport & logistics | 2025 |
| Sinera Property Ltd | Financial services | 2024 |
| Singh Trade Ltd | Hospitality | 2026 |
| Sinis Cars Ltd | Wholesale & retail | 2025 |
| Sinoposhia S Limited | Health & social care | 2021 |
| SIR Bayu Logistics Ltd | Transport & logistics | 2025 |
| Sira Concepts Limited | Other services | 2009 |
| Siruti Ltd | Administrative & support | 2017 |
| SIS Construct Ltd | Extraterritorial | 2023 |
| Sisters Activities CIC | Education | 2025 |
| Sisters United League Ltd | Arts & recreation | 2026 |
| Site Facilities Services Ltd | Construction | 2021 |
| Site Remedial Services Limited | Construction | 2000 |
| SIX2EIGHT House Ltd | Real estate | 2017 |
| SJA Transport Services Ltd | Transport & logistics | 2026 |
| SJI Sports Ltd | Wholesale & retail | 2019 |
| SJM Business Solutions Limited | Energy | 2026 |
| SJR Hire Limited | Administrative & support | 2019 |
| SJS Management Ltd | Financial services | 2016 |
| SK Buy and Rent Limited | Real estate | 2026 |
| SK Comfort Health Care Limited | Health & social care | 2023 |
| SK Elite Staffing Limited | Administrative & support | 2025 |
| SK Express Retail Ltd | Wholesale & retail | 2026 |
| SKA Beauty Ltd | Other services | 2025 |
| SKA IT Solutions Limited | Information & communication | 2023 |
| Skeja Services Limited | Construction | 2016 |
| Skill Sports Ltd | Education | 2025 |
| Skilled Consulting Ltd | Hospitality | 2014 |
| Skilled DRY Lining Ltd | Construction | 2019 |
| Skilledbeyond Ltd | Information & communication | 2023 |
| Skillesteem Ltd | Financial services | 2023 |