| Serendipity Media Limited | Administrative & support | 2013 |
| Serendipity Soirees Ltd | Administrative & support | 2026 |
| Serene Apartments Ltd | Hospitality | 2019 |
| Serene Hive Recruitment Ltd | Administrative & support | 2023 |
| Serene Personnel Ltd | Administrative & support | 2021 |
| Serene Specialised Healthcare Limited | Administrative & support | 2021 |
| Serene Vital Care Limited | Health & social care | 2025 |
| Serenicare Limited | Manufacturing | 2025 |
| Serenigy Limited | Health & social care | 2024 |
| Serenity Massage MK Limited | Hospitality | 2026 |
| Serenity Recruitment Group Ltd | Administrative & support | 2023 |
| Serenity Roofing & Guttering Ltd | Construction | 2026 |
| Sergiu Serban Ltd | Construction | 2013 |
| Series 72 Limited | Real estate | 2005 |
| Series 72 Nominees Limited | Real estate | 2016 |
| Seronera Capital Partners Limited | Administrative & support | 2019 |
| Seronera Developments Limited | Real estate | 2020 |
| Serrado Trading Import and Export Ltd. | Wholesale & retail | 2025 |
| Serve First CX Ltd | Information & communication | 2019 |
| Serversource Holdings Limited | Information & communication | 2005 |
| Serversource Limited | Professional & scientific | 2001 |
| Servet Catering Ltd | Wholesale & retail | 2018 |
| Serviced Club Limited | Hospitality | 2023 |
| Serviceedge Tech Ltd | Information & communication | 2024 |
| Servsys Technologies Ltd | Administrative & support | 2022 |
| Servy Investments Ltd | Financial services | 2020 |
| Serwin Synergy Ltd | Extraterritorial | 2019 |
| Sesc Solutions Group Ltd | Construction | 2022 |
| SET Copyrights Limited | Information & communication | 1960 |
| Seth Tolentino Limited | Health & social care | 2023 |
| Sethlands Ltd | Real estate | 2008 |
| Setient Ltd | Information & communication | 2019 |
| Seun Onakoya Properties Limited | Real estate | 2022 |
| Sevan Digital Limited | Information & communication | 2014 |
| Sevastiyan's Electrical Solutions Ltd | Construction | 2021 |
| Seven Enterprises Ltd | Hospitality | 2018 |
| Seven Tiers Ltd | Health & social care | 2023 |
| Sevenhills Assets Ltd | Real estate | 2024 |
| Seventhday Holdings Ltd | Professional & scientific | 2010 |
| Severin Engineering Solutions Ltd | Manufacturing | 2010 |
| Sevinalas Ltd | Construction | 2023 |
| Sevroll UK Ltd. | Wholesale & retail | 2009 |
| SEW and Save Limited | Wholesale & retail | 2023 |
| SEW Glorious Ltd | Manufacturing | 2021 |
| Sew+Sew Winery Ltd | Manufacturing | 2023 |
| Sexton Brothers Limited | Wholesale & retail | 2016 |
| Seykem and Sons Limited | Public administration | 2021 |
| Seymour House Freehold Limited | Households | 2007 |
| Seymour Pharmacie Limited | Wholesale & retail | 2007 |
| SF Conway Holdings Limited | Financial services | 2024 |
| SF Invest Ltd | Real estate | 2024 |
| SFA Horizon Ltd | Administrative & support | 2014 |
| Sfbb Transport Ltd | Construction | 2024 |
| SFG Consulting Ltd | Professional & scientific | 2024 |
| SFS MK Ltd | Financial services | 2024 |
| SFX IT Ltd | Information & communication | 2022 |
| SG Aqua Services & Technologies Limited | Wholesale & retail | 2013 |
| SG Tools Ltd | Professional & scientific | 2025 |
| Sg&P Ltd | Real estate | 2018 |
| SGA Letting Ltd | Real estate | 2023 |
| SGB Courier Ltd. | Transport & logistics | 2016 |
| Sgillani Limited | Real estate | 2024 |
| SGK Care Homes Ltd | Health & social care | 2023 |
| SGK Construction Services Ltd | Administrative & support | 2023 |
| SGK Services Ltd | Administrative & support | 2017 |
| Sgnd Ltd | Transport & logistics | 2026 |
| Sgrn Private Limited | Health & social care | 2021 |
| SGV Accounting Ltd | Professional & scientific | 2023 |
| SGV Styledge Limited | Construction | 2019 |
| SH Bristol Limited | Hospitality | 2019 |
| SH Crown Ltd | Construction | 2024 |
| SH Estimating Services Ltd | Professional & scientific | 2019 |
| SH Exeter Limited | Hospitality | 2019 |
| SH Gloucester Quays Limited | Hospitality | 2019 |
| SH Mechanical Engineering Ltd | Construction | 2026 |
| SH Racing Top Fuel Ltd | Manufacturing | 2026 |
| SH Sonography Ltd | Health & social care | 2025 |
| SH4 Property Ltd | Real estate | 2023 |
| Shaan Aleem Tech Ltd | Information & communication | 2024 |
| Shaan Residencies Ltd | Real estate | 2024 |
| Shabs Bistro Ltd | Hospitality | 2024 |
| Shacare Limited | Health & social care | 2018 |
| Shad Removals and Courier Service Ltd | Transport & logistics | 2026 |
| Shadat Grill Limited | Hospitality | 2026 |
| Shaddai Investments Ltd | Real estate | 2025 |
| Shaddai Properties Ltd | Real estate | 2025 |
| Shadow Autoworx Ltd | Wholesale & retail | 2025 |
| Shadow's Land Limited | Other services | 2010 |
| Shaebridge Estates Limited | Real estate | 2025 |
| Shafisons Ltd | Wholesale & retail | 2025 |
| Shah & Bhatia Properties Ltd | Real estate | 2022 |
| Shah & Sandhu Investments Limited | Real estate | 2024 |
| Shah Interior Designing Ltd | Construction | 2021 |
| Shah's Bletchley Ltd | Hospitality | 2026 |
| Shahena Limited | Hospitality | 2026 |
| Shahr Ltd | Transport & logistics | 2020 |
| Shahram Haider Ltd | Wholesale & retail | 2026 |
| Shahs Cars Ltd | Wholesale & retail | 2025 |
| Shahzadeh Ltd | Transport & logistics | 2018 |
| Shahzadeh Properties Ltd | Real estate | 2023 |