| Residential Signs (UK) Ltd | Construction | 2022 |
| Respair Therapy C.I.C. | Health & social care | 2023 |
| Retro Custom Limited | Wholesale & retail | 2007 |
| Retro Rides Gathering Ltd | Arts & recreation | 2009 |
| Revae Tax Technology Limited | Information & communication | 2023 |
| Rewirement Limited | Professional & scientific | 2022 |
| Richmond House Group Limited | Financial services | 1997 |
| Richmond House Insurance Brokers Limited | Financial services | 1976 |
| Rikta Coaching Ltd | Education | 2026 |
| Rise Accountancy Solutions Ltd | Professional & scientific | 2026 |
| Rise Learning Ltd | Professional & scientific | 2015 |
| Ristol Salvage Limited | Professional & scientific | 2006 |
| RJM Electronics Ltd | Extraterritorial | 2022 |
| RMA Property Investment Limited | Real estate | 2022 |
| Robbtawn Ltd. | Information & communication | 2020 |
| Robecks Ltd | Administrative & support | 2025 |
| Roland Mews Management Limited | Households | 1991 |
| RR Transport Services Ltd | Transport & logistics | 2020 |
| Rubarb Ltd | Wholesale & retail | 2023 |
| Rudi Poon and Company Limited | Professional & scientific | 2022 |
| S and V Aesthetics Ltd | Other services | 2025 |
| S2S Controls Limited | Energy | 2023 |
| Satellite Wifi Ltd | Information & communication | 2024 |
| Savvy Geek Ltd | Wholesale & retail | 2024 |
| Sawbridgeworth Dental Surgery Limited | Health & social care | 2008 |
| Sayson Limited | Education | 2022 |
| Scaffolding IT Solutions Ltd | Information & communication | 2016 |
| Scott Pharma Solutions Ltd | Professional & scientific | 2014 |
| Screenbond Limited | Manufacturing | 1980 |
| Sepa Property Ltd | Information & communication | 2022 |
| Seven Roe's Malting Limited | Households | 2000 |
| Seven Star Resources Ltd | Financial services | 2018 |
| SG7 Baldock Spice Ltd | Hospitality | 2025 |
| SG7 Pizza Ltd | Hospitality | 2026 |
| Sgcs Care Limited | Health & social care | 2015 |
| Shaktishiv Ltd | Wholesale & retail | 2023 |
| Shire END Close Management Company Limited | Real estate | 2016 |
| Siam Candy Limited | Manufacturing | 2025 |
| Sigma Office Limited | Information & communication | 2000 |
| Signal Social Ltd | Professional & scientific | 2025 |
| Simon David Cleaning Services Limited | Administrative & support | 2004 |
| SJT Property Development Ltd | Construction | 2020 |
| Skdl Investment Ltd | Real estate | 2020 |
| Skyline Consulting Ltd | Professional & scientific | 2018 |
| Smart Design Fabrication Limited | Construction | 2021 |
| Smith & Curran Consulting Limited | Professional & scientific | 2022 |
| Smoothie London Ltd | Wholesale & retail | 2022 |
| Snsn Food and Wine Ltd | Wholesale & retail | 2024 |
| SO5 Limited | Information & communication | 2025 |
| South Mansions (Gondar Gardens)Rtm Company Limited | Households | 2009 |
| Space Revive Ltd | Construction | 2025 |
| Sparklebus Limited | Information & communication | 2024 |
| Sports Therapy 4U Ltd. | Health & social care | 2018 |
| Square Point Design Ltd | Professional & scientific | 2023 |
| SRG Gaming Ltd | Professional & scientific | 2026 |
| SRM Events Limited | Hospitality | 2026 |
| SRM Property Investments Limited | Real estate | 2017 |
| ST John's ROW Management Company Limited | Households | 2005 |
| Stanburys Limited | Professional & scientific | 1988 |
| Stanvak Holdings Limited | Financial services | 2024 |
| Stanvak Investments Limited | Financial services | 2024 |
| Stayput Covers Limited | Manufacturing | 1995 |
| Stephen Fleming Limited | Professional & scientific | 2010 |
| Sterling Carpet Care Limited | Administrative & support | 2006 |
| Sterling Paris Ltd | Arts & recreation | 2022 |
| Stevenage Overnight Parcels Limited | Transport & logistics | 2020 |
| STEWARDHEALTHCARE247PROFESSIONALS Ltd | Public administration | 2021 |
| Strickland Search Limited | Administrative & support | 2014 |
| Studio 28UK Limited | Professional & scientific | 2026 |
| Style Dance School Ltd | Arts & recreation | 2017 |
| Sudlow Property Associates Limited | Other services | 2016 |
| Sugar Trades Ltd | Wholesale & retail | 2019 |
| Sunrise Cafe Catering Limited | Hospitality | 2025 |
| Supernormal Graphics Ltd | Professional & scientific | 2026 |
| Sykes Carpentry Ltd | Construction | 2026 |
| T&S Builders (Herts) Limited | Administrative & support | 2022 |
| Tarver Productions Ltd | Manufacturing | 2006 |
| Taylor Bennett Partners LLP | | 2010 |
| Taylor Pipeline Services Limited | Construction | 2017 |
| TC Property Maintenance London Ltd | Construction | 2020 |
| Templar Mortgage Solutions Limited | Financial services | 2016 |
| Templars Building Surveyors Limited | Professional & scientific | 1989 |
| Territory Furniture Ltd | Wholesale & retail | 2025 |
| THE Artisan Food Trail Limited | Extraterritorial | 2008 |
| THE Beauty & Soul Collective Ltd | Other services | 2026 |
| THE Carpet Factory (Herts) Limited | Wholesale & retail | 1998 |
| THE Cock OBH Limited | Hospitality | 2018 |
| THE Colour Room Hair Ltd | Other services | 2019 |
| THE Degree GAP Limited | Education | 2024 |
| THE Extension Centre Limited | Construction | 1995 |
| THE Fauna Flow Ltd | Other services | 2021 |
| THE Good the MAD the Ugly Props Ltd | Water & waste | 2025 |
| THE Great British Sausage Company Ltd | Administrative & support | 2008 |
| THE High END HMO Ltd | Extraterritorial | 2023 |
| THE Hooka LLP | | 2013 |
| THE Image House (UK) Ltd | Professional & scientific | 2005 |
| THE Knights Templar School | Education | 2011 |
| THE Lamp Company Limited | Manufacturing | 1993 |
| THE Media Tree Limited | Information & communication | 2021 |
| THE Mortgage Station Ltd | Financial services | 2019 |