| RCI Plastering Ltd | Construction | 2024 |
| Rcog Holdings Limited | Administrative & support | 2016 |
| RCQ Consultancy Limited | Professional & scientific | 2019 |
| RCS Care Ltd | Professional & scientific | 2020 |
| RCS Commercial Management Ltd | Professional & scientific | 2016 |
| RCS Consulting Ltd | Professional & scientific | 2022 |
| RCS Groundworks Limited | Extraterritorial | 2011 |
| RCS Projects Ltd | Construction | 2025 |
| RCU Consultancy Ltd | Information & communication | 2021 |
| RD Bromley Building Solutions Ltd | Construction | 2023 |
| RD Gray Consultancy Ltd | Professional & scientific | 2025 |
| RD Services (Northampton) Services Limited | Transport & logistics | 2017 |
| RDA Consultant Architects LLP | | 2010 |
| RDB Engineering Solutions Ltd | Administrative & support | 2010 |
| RDF (Investments) Limited | Construction | 2004 |
| Rdpo Enterprises Ltd | Information & communication | 2025 |
| Rdvault Limited | Information & communication | 2017 |
| Re-Gen IT Ltd | Wholesale & retail | 2010 |
| RE4MIT Ltd | Information & communication | 2019 |
| Reaben Ltd | Wholesale & retail | 2024 |
| Reach FAR Performance Improvement Limited | Professional & scientific | 2016 |
| Reach Media Services Ltd | Professional & scientific | 2019 |
| Reach OUT Autism CIC | Health & social care | 2022 |
| Reach-Out Care Limited | Health & social care | 1999 |
| React Brazilian Jiu-Jitsu Academy Ltd | Arts & recreation | 2026 |
| React Computer Partnership Limited | Information & communication | 2002 |
| React Main UK Ltd | Construction | 2015 |
| Reactive Asbestos Management Limited | Professional & scientific | 2025 |
| Reactive Services North West Ltd | Construction | 2022 |
| Read Auto-Tec Limited | Wholesale & retail | 2003 |
| Reading Holdings Limited | Professional & scientific | 1993 |
| Readingsfinest Ltd | Education | 2025 |
| Readlane Property Management Limited | Households | 1983 |
| Ready Golf Ltd | Hospitality | 2025 |
| Ready SET Clean Ltd | Administrative & support | 2025 |
| Readysetgo Ltd | Wholesale & retail | 2025 |
| Real (High Lane) Limited | Construction | 2017 |
| Real Good Research Limited | Professional & scientific | 2025 |
| Real Life Gym CIC | Arts & recreation | 2026 |
| Real Life Health & Fitness Limited | Other services | 2017 |
| Real Life Health and Fitness Online Limited | Arts & recreation | 2019 |
| Real LSE Limited | Construction | 2020 |
| Real Places Limited | Construction | 2021 |
| Real Productions Limited | Professional & scientific | 2025 |
| Real SW Limited | Construction | 2020 |
| Realbest Builders Limited | Construction | 2011 |
| Realbuzz Group Limited | Administrative & support | 2019 |
| REALCARE24/7 Services Private Ltd | Administrative & support | 2026 |
| Realestatereach Ltd | Real estate | 2024 |
| Realine Studio Group Ltd | Wholesale & retail | 2021 |
| Reality Compliance Limited | Other services | 2012 |
| Really Clean JET Wash Services Limited | Administrative & support | 2003 |
| Realtor Properties Limited | Real estate | 2021 |
| Reardon IS Ltd | Information & communication | 2013 |
| Rebecca Conway Psychology Ltd | Health & social care | 2023 |
| Rebirthx Ltd | Information & communication | 2018 |
| Rebrite Limited | Construction | 2011 |
| Receevit Ltd | Information & communication | 2025 |
| Recharge Research Ltd | Professional & scientific | 2023 |
| Recolo Assemblies Limited | Administrative & support | 2012 |
| Record City Creations Limited | Wholesale & retail | 2023 |
| Recovereaze Ltd | Transport & logistics | 2025 |
| Recovery Support Limited | Health & social care | 2015 |
| Recruit Northern Ltd | Administrative & support | 2014 |
| Recruit Regional Limited | Administrative & support | 2026 |
| Recruit Wealth Ltd | Administrative & support | 2020 |
| RECRUITING4YOU Ltd | Administrative & support | 2024 |
| Recruitrite Limited | Administrative & support | 2018 |
| Recruits of Manchester Ltd | Administrative & support | 2025 |
| Recruvision Ltd | Administrative & support | 2026 |
| Recsquared Limited | Information & communication | 2025 |
| Recyc Eco Consultants Ltd | Professional & scientific | 2022 |
| Recycle Centre Inc Ltd | Water & waste | 2023 |
| Recycle-It! (Bolton) CIC | Transport & logistics | 2021 |
| Red 11 Limited | Information & communication | 2015 |
| Red 1978 Ltd | Hospitality | 2019 |
| Red 2 Black Snooker Ltd | Arts & recreation | 2024 |
| Red Autumn Ltd | Professional & scientific | 2005 |
| Red Betty Designs Limited | Administrative & support | 2022 |
| Red Brick Theatre Ltd | Arts & recreation | 2024 |
| Red Bricks Properties Ltd | Real estate | 2015 |
| Red Bridge FM Ltd | Administrative & support | 2025 |
| Red Cat Data Ltd | Information & communication | 2013 |
| Red Chilli Design Limited | Manufacturing | 2009 |
| Red Gables (Shap) Management Company Limited | Households | 2010 |
| Red Lion Builds Ltd | Construction | 2021 |
| Red Offshore Ltd | Professional & scientific | 2024 |
| Red Pepper Nutrition LLP | | 2015 |
| Red Planet Productions Ltd | Administrative & support | 2017 |
| Red RAY Emporium Ltd | Wholesale & retail | 2024 |
| Red RAY Solutions Limited | Wholesale & retail | 2017 |
| Red Rock Software Works Limited | Information & communication | 2022 |
| Red Rose Airport Parking Ltd | Transport & logistics | 2026 |
| Red Rose Consulting Limited | Professional & scientific | 2026 |
| Red Rose Directories Ltd | Information & communication | 2009 |
| Red Rose Magazines Ltd | Extraterritorial | 2024 |
| Red Rose Pallet & Case Co Limited | Wholesale & retail | 2002 |
| Red Rose Plant Service and Repairs Limited | Manufacturing | 2002 |
| Red Rose Strategic Consultancy Ltd | Professional & scientific | 2025 |
| Red Spice Bolton Limited | Hospitality | 2025 |