| Sirius Bidco Limited | Other services | 2021 |
| Sirius Holdco Limited | Other services | 2021 |
| Sirius Midco Limited | Other services | 2021 |
| Sirius OS Solutions Limited | Other services | 2017 |
| Siro Holdings Limited | Real estate | 2022 |
| Siro Investments Limited | Financial services | 2022 |
| Sirom Aviation Limited | Transport & logistics | 2017 |
| Sirtec Limited | Hospitality | 2005 |
| Sister Brows Ltd | Education | 2017 |
| Sisterhood HQ Ltd | Other services | 2022 |
| Sisterhood Salons Limited | Other services | 2024 |
| SIT in Your Throne Ltd | Construction | 2019 |
| SIT Logistics Ltd | Transport & logistics | 2025 |
| SIT Property Solutions Ltd | Construction | 2022 |
| Site Check Solutions Ltd | Construction | 2025 |
| Site Engineering and Management Services Ltd | Professional & scientific | 2023 |
| Site HUT Limited | Construction | 2017 |
| Site Management Service Limited | Construction | 2013 |
| Site One Towers Limited | Information & communication | 2022 |
| Site Safe Traffic Solutions Limited | Transport & logistics | 2016 |
| Site Services (Northern) Limited | Professional & scientific | 2001 |
| Site Supply (NW) Ltd | Construction | 2018 |
| Siti Prop Co Limited | Real estate | 2023 |
| Sitiawan Ltd | Real estate | 2019 |
| Sittacus Solutions Limited | Wholesale & retail | 2019 |
| SIU Design LAB Limited | Professional & scientific | 2018 |
| Siva MK Properties Ltd | Real estate | 2021 |
| Siwail Breakfast Ltd | Hospitality | 2025 |
| Siwail Coffee Shop Ltd | Hospitality | 2024 |
| SIX Aigburth Drive Ltd | Households | 2022 |
| SIX Figure Systems Ltd | Education | 2023 |
| SIX Foot Swan Ltd | Arts & recreation | 2017 |
| SIX Hackins HEY Ltd | Other services | 2018 |
| SIX People Away CIC | Education | 2026 |
| SIX Pieces Limited | Hospitality | 2017 |
| SIX the Crescent Management Company Limited | Households | 2004 |
| SIX Two Five (NW) Ltd | Hospitality | 2022 |
| Sixo Systems Limited | Information & communication | 2011 |
| Sixsmith Ltd | Wholesale & retail | 2022 |
| Sixsmiths ( Renew ) Ltd | Construction | 2017 |
| Sixteenq Ltd | Households | 2020 |
| Sixties Ltd | Wholesale & retail | 2011 |
| Sixty Kitchen Ltd | Hospitality | 2022 |
| Siya Diagnostics Limited | Health & social care | 2013 |
| Siya Imaging Ltd | Professional & scientific | 2022 |
| Sizab Investments Limited | Other services | 2016 |
| Sizaro Ltd | Wholesale & retail | 2024 |
| Sizzaro Ltd | Hospitality | 2025 |
| Sizzlaz County Ltd | Hospitality | 2025 |
| Sizzlaz Old Swan L13 Ltd | Hospitality | 2025 |
| Sizzlaz Two Old Swan Ltd | Hospitality | 2023 |
| Sizzle Fresh Food Ltd | Hospitality | 2024 |
| Sizzle Grill Ltd | Hospitality | 2019 |
| SJ & J Channel Solutions Limited | Information & communication | 2012 |
| SJ Claims Group Ltd | Professional & scientific | 2025 |
| SJ Competitions NW Ltd | Wholesale & retail | 2025 |
| SJ Developments North West Ltd | Construction | 2025 |
| SJ Food & Wine Retail Ltd | Wholesale & retail | 2026 |
| SJ Holiday Lettings Limited | Hospitality | 2021 |
| SJ Mcmurrie Integrated Services Limited | Professional & scientific | 2016 |
| SJ Property Estates Limited | Construction | 2025 |
| SJ Property Liverpool Limited | Real estate | 2026 |
| SJ Services (Liverpool) Limited | Construction | 2012 |
| SJ Services Maintenance Liverpool Limited | Real estate | 2022 |
| SJ Sports Ltd | Arts & recreation | 2026 |
| SJA (Liverpool) Limited | Other services | 2010 |
| SJA Car Sales Ltd | Wholesale & retail | 2016 |
| SJA Karate Ltd | Other services | 2019 |
| SJB GAS Engineer Limited | Construction | 2020 |
| Sjbdrinks Ltd | Hospitality | 2025 |
| SJC Investments Limited | Real estate | 2022 |
| SJD Film Productions Ltd | Information & communication | 2021 |
| SJD Roofing Group Ltd | Construction | 2024 |
| SJD2015 Ltd | Professional & scientific | 2015 |
| SJF Communications Limited | Construction | 2019 |
| SJF Online Ltd | Other services | 2016 |
| SJF Seventy SIX Holdings Ltd | Financial services | 2022 |
| SJHOLDINGS2025 Ltd | Real estate | 2025 |
| Sjhroofing Ltd | Construction | 2022 |
| SJI Haulage Ltd | Transport & logistics | 2021 |
| SJJ Advisory Limited | Professional & scientific | 2022 |
| SJJ Contracts North Limited | Construction | 2023 |
| SJK Incorporated Ltd | Administrative & support | 2024 |
| SJK Properties Ltd | Real estate | 2003 |
| Sjkh Partnership Ltd | Hospitality | 2021 |
| SJL Leisure Ltd | Other services | 2011 |
| SJM Driver Training and Operator Compliance Ltd | Education | 2026 |
| SJM IT Consultancy Ltd | Information & communication | 2023 |
| Sjme Ltd | Professional & scientific | 2024 |
| SJN Developments North West Ltd | Real estate | 2020 |
| Sjon Heating and Plumbing Ltd | Construction | 2021 |
| SJP Electrical (NW) Ltd | Construction | 2011 |
| SJP Joinery and Construction Ltd | Construction | 2025 |
| SJP Secure Solutions Ltd | Administrative & support | 2025 |
| SJP Security Limited | Administrative & support | 2026 |
| SJP Wide Loads Ltd | Transport & logistics | 2025 |
| SJR 2014 Limited | Professional & scientific | 2014 |
| SJR Building & Maintenance Ltd | Construction | 2025 |
| SJR Roofing Ltd | Construction | 2025 |
| SJR Transport Ltd | Transport & logistics | 2026 |