| Shining Diamond Investments Limited | Real estate | 2022 |
| Shining Diamond Properties Ltd | Real estate | 2021 |
| Shining Light Initiative CIC | Education | 2025 |
| Shinton Limited | Real estate | 2008 |
| Shinwari Dera Restaurant Ltd | Hospitality | 2025 |
| Shiny Touch Cleaning Ltd | Administrative & support | 2025 |
| Ship Mountain Ltd | Real estate | 2023 |
| Shipton Grange Residents Company Limited | Households | 1998 |
| Shipton Healthcare Ltd | Health & social care | 2022 |
| Shire Care (Nursing & Residential Homes) Limited | Health & social care | 1984 |
| Shire Care Holdings Limited | Professional & scientific | 1989 |
| Shire Care Management Services Limited | Extraterritorial | 2002 |
| Shire Care Properties Limited | Construction | 1999 |
| Shire Care Property Developments Limited | Construction | 1995 |
| Shirts.Co.Uk Limited | Wholesale & retail | 2000 |
| Shiv Shakti Leicester Ltd | Wholesale & retail | 2022 |
| Shivay Limited | Transport & logistics | 2020 |
| Shivay Scaffolding Limited | Construction | 2024 |
| SHK Design Ltd | Information & communication | 2010 |
| SHK Services Limited | Health & social care | 2009 |
| Shlama Limited | Wholesale & retail | 2010 |
| Shobha Property Management & Lettings Ltd | Real estate | 2023 |
| Shobika Investments Limited | Real estate | 2025 |
| Shop and Save Forecourt Ltd | Wholesale & retail | 2016 |
| Shop-Pods Limited | Real estate | 2019 |
| Shopkudu Ltd | Wholesale & retail | 2025 |
| Shoplight Holdings Limited | Financial services | 2023 |
| Shoplight Limited | Manufacturing | 2014 |
| Shoplystic Limited | Wholesale & retail | 2025 |
| Shopping Basket Properties Ltd | Real estate | 2017 |
| Shopsozzle Ltd | Wholesale & retail | 2025 |
| Shortall Properties Limited | Real estate | 2024 |
| Shotbolt Close Ramsey Management Company Limited | Households | 2023 |
| Showcase Couriers Ltd | Wholesale & retail | 2020 |
| Showfields Limited | Real estate | 1996 |
| Shrekas Ltd | Transport & logistics | 2025 |
| Shubham Finance Limited | Real estate | 2025 |
| Shumba Meats. Ltd. | Manufacturing | 2019 |
| Shwr Ltd | Hospitality | 2019 |
| Shyzion UK Ltd | Wholesale & retail | 2023 |
| SI FI Films Limited | Information & communication | 2019 |
| SI FI Productions Limited | Information & communication | 2009 |
| Si's Developments Ltd | Construction | 2019 |
| SIA PB Ltd | Hospitality | 2026 |
| Sibga Technical Limited | Manufacturing | 2025 |
| Sibijon Trans Courier Ltd | Transport & logistics | 2026 |
| Sibzone Ltd | Wholesale & retail | 2024 |
| Sicars 80 Ltd | Wholesale & retail | 2020 |
| Sidar Investment Ltd | Wholesale & retail | 2020 |
| Side Income Expert Limited | Wholesale & retail | 2025 |
| Sideselct Limited | Wholesale & retail | 2025 |
| Sidwell Farms Ltd | Agriculture & fishing | 2020 |
| Sieron Trans Ltd | Transport & logistics | 2018 |
| Sight & Sound Security Limited | Public administration | 2006 |
| Sigma Financial Services Ltd | Professional & scientific | 2016 |
| Sigma India Holdings Limited | Energy | 2012 |
| Sigma India Investments Limited | Energy | 2012 |
| Sigma Ledger Ltd | Professional & scientific | 2025 |
| Sigma Scaffolding Solutions Ltd | Construction | 2023 |
| SIGMA47 Solutions Ltd | Health & social care | 2026 |
| Signalpro UK Ltd | Information & communication | 2023 |
| Signature Aesthetic Clinic Ltd | Other services | 2024 |
| Signature Beauty & Co UK Ltd | Other services | 2022 |
| Signature Club Ltd | Professional & scientific | 2023 |
| Signature Joinery & Construction Ltd | Construction | 2017 |
| Signature Labels Ltd | Wholesale & retail | 2025 |
| Signature Labourer Ltd | Administrative & support | 2019 |
| Signature Lets Ltd | Real estate | 2026 |
| Signature Long Haul Ltd | Administrative & support | 2020 |
| Signature Mobility Ltd | Manufacturing | 2025 |
| Signature Music Festival CIC | Arts & recreation | 2019 |
| Signature Precision Flooring Ltd | Construction | 2025 |
| Signature Solutions Ltd. | Professional & scientific | 2017 |
| Signature Suites Ltd | Hospitality | 2017 |
| Signature Transport Ltd | Transport & logistics | 2025 |
| SIK SIX Ltd | Wholesale & retail | 2020 |
| Sika Holdings Limited | Financial services | 2018 |
| Sikla UK Limited | Manufacturing | 2003 |
| SIL Engineering Limited | Professional & scientific | 2024 |
| Silent Chef Ltd | Information & communication | 2024 |
| Silesia Services Ltd | Transport & logistics | 2020 |
| Silinor Limited | Construction | 2025 |
| Silk Road Kitchen Ltd | Hospitality | 2026 |
| Silk Road Spice Limited | Hospitality | 2026 |
| Silnic Trans Ltd | Administrative & support | 2019 |
| Silo Services Limited | Construction | 1988 |
| Silva Road Ltd | Transport & logistics | 2025 |
| Silva Seidi Ltd | Health & social care | 2026 |
| Silver Arrow Cars Ltd | Wholesale & retail | 2025 |
| Silver Badger Technologies Limited | Information & communication | 2025 |
| Silver Tyres Limited | Wholesale & retail | 2021 |
| Silverbirch Property Investments Ltd | Real estate | 2019 |
| Silvercircle PTE Limited | Health & social care | 2025 |
| Silverdock Limited | Information & communication | 1995 |
| Silverlight Property Ltd | Real estate | 2016 |
| Silverline Developments (Cambs) Limited | Construction | 2014 |
| Silverwood Care Peterborough Ltd | Health & social care | 2021 |
| Silverwood Investment Group Limited | Real estate | 2023 |
| Silvra Solutions Ltd | Professional & scientific | 2025 |
| Simba Slots Limited | Information & communication | 2025 |