| S2TRIBE Ltd | Professional & scientific | 2025 |
| S4 Invest Limited | Transport & logistics | 2023 |
| S4I-COMMUNITY Ltd | Extraterritorial | 2023 |
| S6 Travel Ltd | Administrative & support | 2026 |
| S6 Wraps Limited | Other services | 2015 |
| SA & MJ Properties Ltd | Real estate | 2023 |
| SA Claims Ltd | Administrative & support | 2007 |
| SA Drylining Ltd | Construction | 2011 |
| SA Mash Care Solutions Ltd | Health & social care | 2014 |
| SA Property (Northampton) Ltd | Real estate | 2021 |
| SA Taverns Ltd | Hospitality | 2019 |
| SAA Aviation Services Limited | Other services | 2023 |
| Saad London Ltd | Manufacturing | 2017 |
| Saai Collection Limited | Wholesale & retail | 2026 |
| Saascribe Media Ltd | Administrative & support | 2015 |
| Saat Healthcare Limited | Professional & scientific | 2014 |
| SAB Fire Ltd | Construction | 2018 |
| Saba Medical Ltd | Health & social care | 2024 |
| Sabai Sabai (Birmingham) Limited | Hospitality | 2014 |
| Sabai Sabai (Harborne) Ltd. | Hospitality | 2011 |
| Sabai Sabai (Moseley) Ltd. | Hospitality | 2008 |
| Sabai Sabai (Solihull) Ltd | Hospitality | 2022 |
| Sabai Sabai (Stratford) Ltd. | Hospitality | 2015 |
| Sabatera Limited | Hospitality | 2025 |
| Saber Management UK Limited | Professional & scientific | 2013 |
| Saber Productions Limited | Information & communication | 2019 |
| Sabicsarl Limited | Administrative & support | 2014 |
| Sabin Holdings Limited | Real estate | 2025 |
| Sabita Anaesthetics Ltd. | Health & social care | 2015 |
| Sabolik Property Ltd | Real estate | 2023 |
| Sabreclay Limited | Households | 1981 |
| SAC & Co Manufacturing Limited | Manufacturing | 2023 |
| Sachas NG Limited | Administrative & support | 2026 |
| Sackey Car Finance Ltd | Financial services | 2025 |
| Sada Properties UK Ltd | Real estate | 2025 |
| Sada Trans Ltd | Transport & logistics | 2022 |
| Saddler Accessories Ltd | Wholesale & retail | 2021 |
| Saeco Clean Ltd | Administrative & support | 2021 |
| Saeloc Limited | Wholesale & retail | 1999 |
| SAF Security Solutions Ltd | Other services | 2020 |
| Safar Taxis Rental Ltd | Transport & logistics | 2025 |
| Safariclick Ltd | Administrative & support | 2018 |
| Safaris Healthcare. Limited | Health & social care | 2020 |
| Safe FM Services Limited | Administrative & support | 2023 |
| Safe Momentum Limited | Professional & scientific | 2024 |
| Safe Road Tyres Ltd | Wholesale & retail | 2026 |
| Safe Transitions Care Ltd | Health & social care | 2020 |
| Safeguarding SW Limited | Health & social care | 2023 |
| Safehands Music Ltd | Information & communication | 2021 |
| Safelink Operations Limited | Professional & scientific | 2021 |
| Safely Ltd | Administrative & support | 2020 |
| Safely Recruitment Ltd | Administrative & support | 2018 |
| Safer Community Guardian CIC | Transport & logistics | 2026 |
| Safety Consulting Limited | Professional & scientific | 2021 |
| Safety Estate Ltd | Real estate | 2018 |
| Safety Solutions (Northampton) Limited | Professional & scientific | 2003 |
| Safety Training and Consultancy Limited | Professional & scientific | 2016 |
| Saffa Investments Ltd | Construction | 2020 |
| Saffetway Ltd | Hospitality | 2018 |
| Saffron & Silk Lounge Ltd | Hospitality | 2026 |
| Saffron 813 Limited | Wholesale & retail | 2013 |
| Saffron International Ltd | Hospitality | 2023 |
| Saffron Property Group Limited | Real estate | 2025 |
| Saffron Watford Limited | Hospitality | 2024 |
| Safi Holding Ltd | Real estate | 2024 |
| Safov Ltd | Construction | 2019 |
| Safta Andrei Ltd | Administrative & support | 2017 |
| Safwan Hira Real Estate Limited | Construction | 2019 |
| Sagacious Software Ltd | Real estate | 2016 |
| Sage Decorating Limited | Extraterritorial | 2019 |
| Sagma Homes Ltd | Construction | 2022 |
| SAH IT Solutions Ltd | Information & communication | 2021 |
| SAH Property One Ltd | Real estate | 2022 |
| SAH Trans Logistics Ltd | Transport & logistics | 2025 |
| Sahajaanand Limited | Hospitality | 2025 |
| Sahar Healthcare Ltd | Health & social care | 2025 |
| Saharasyd Ltd | Health & social care | 2022 |
| Sahins Supermarket Limited | Wholesale & retail | 2021 |
| SAI SAI Limited | Hospitality | 2012 |
| SAI Studio Ltd | Wholesale & retail | 2024 |
| Saifar Motors Ltd | Wholesale & retail | 2025 |
| Sailvox Ltd | Wholesale & retail | 2025 |
| Saim Technologies Ltd | Information & communication | 2025 |
| Saint Isidore Labourer LLP | | 2023 |
| Saints Electrical & Security Ltd | Construction | 2011 |
| Saints Rugby Limited | Professional & scientific | 1995 |
| Saintsol Holdings Ltd | Financial services | 2026 |
| Saitel Services Ltd | Information & communication | 2022 |
| Sajid ALI Enterprises Ltd | Wholesale & retail | 2024 |
| Sajones Properties Limited | Real estate | 2022 |
| SAK Assistants Limited | Health & social care | 2025 |
| Sakura Sushi Ltd | Hospitality | 2023 |
| Salaam Superstore Limited | Wholesale & retail | 2024 |
| Salcey Limited | Agriculture & fishing | 2017 |
| Salcey Mortgages Ltd | Financial services | 2014 |
| Salcey Precision Engineering Ltd. | Manufacturing | 1987 |
| Saldanha Ltd | Information & communication | 2025 |
| Sales Savvy Limited | Wholesale & retail | 2025 |
| Salestrong (UK) Limited | Professional & scientific | 2013 |
| Salifu Dagarti Foundation | Health & social care | 2006 |