| Rapha Healthcare Solutions Limited | Administrative & support | 2021 |
| Rapid Associates (Commercial) Limited | Construction | 2005 |
| Rapid Associates Limited | Real estate | 1998 |
| Rapid Pixel Racing Ltd | Other services | 2019 |
| Rapid Response Kent Ltd | Construction | 2018 |
| Rapidlei Limited | Other services | 2017 |
| Rapidtrade Ltd | Wholesale & retail | 2025 |
| Rappongi Limited | Transport & logistics | 2021 |
| Rapti Samaj UK CIC | Education | 2023 |
| Rarelive Limited | Construction | 1989 |
| Rasinda Limited | Households | 1978 |
| Rate One Limited | Transport & logistics | 2022 |
| Rated Driving Instructors Ltd | Education | 2017 |
| Ratokar Ltd | Transport & logistics | 2022 |
| Rattle and HUM Ltd | Hospitality | 2011 |
| Ravael Ltd | Transport & logistics | 2014 |
| Rave Property Holdings Limited | Real estate | 2023 |
| Ravelin Ltd | Professional & scientific | 2024 |
| RAX Mortgage Finance Limited | Financial services | 2021 |
| RAY & ROY Limited | Wholesale & retail | 2016 |
| Raykov Ltd | Transport & logistics | 2019 |
| Rayner Brown Construction Limited | Administrative & support | 2011 |
| Rays Qureshi Ltd | Real estate | 2021 |
| Raywood Homes Ltd | Real estate | 2009 |
| Raywood Properties Limited | Construction | 2011 |
| RAZ ALI Ltd | Real estate | 2026 |
| RB Accounting Limited | Professional & scientific | 2002 |
| RB Building Services Construction Ltd | Construction | 2024 |
| RB Kent Property Limited | Real estate | 2024 |
| RB Project Solutions Ltd | Administrative & support | 2026 |
| RBK Catering Limited | Hospitality | 2025 |
| RBL Property Group Ltd | Real estate | 2025 |
| RBT Building Services Ltd | Construction | 2017 |
| RC Care Services Ltd | Health & social care | 2014 |
| RCD Consultants Ltd | Professional & scientific | 2007 |
| RCL Graphics Ltd | Construction | 2010 |
| RCN Motors Limited | Wholesale & retail | 2025 |
| RDB Environmental Consulting Ltd | Professional & scientific | 2020 |
| RDD Expedition Ltd | Transport & logistics | 2023 |
| RDG Logistics Ltd | Transport & logistics | 2025 |
| RDJ Colloids Limited | Manufacturing | 1985 |
| RDL Render Ltd. | Construction | 2010 |
| Re-Fence Ltd | Construction | 2025 |
| Re-Plen Nutrition Ltd | Wholesale & retail | 2024 |
| Re-Wear Fashion Ltd | Wholesale & retail | 2025 |
| Reactive Facilities Services Ltd | Construction | 2011 |
| Real Best Ltd | Hospitality | 2026 |
| Real Connect Estate LLP | | 2018 |
| Real Print & Media Limited | Manufacturing | 2011 |
| Realist Valet Ltd | Wholesale & retail | 2025 |
| Realvine Holdings Ltd | Financial services | 2024 |
| Realvine Properties Ltd | Real estate | 2021 |
| Rear Admiral Games Limited | Information & communication | 2023 |
| Rebecca Court Management Limited | Households | 1990 |
| Rebecca Harle Aesthetics Ltd | Other services | 2023 |
| Rebecca Joy Ltd | Arts & recreation | 2021 |
| Rebirth Clothing Limited | Manufacturing | 2025 |
| Reborn Design Ltd | Professional & scientific | 2026 |
| Rebwar Barber Ltd | Other services | 2023 |
| Recall Medical Ltd | Health & social care | 2024 |
| Reclaim Services Ltd | Wholesale & retail | 2005 |
| Recluse Software Ltd | Information & communication | 2012 |
| Recpro Holdings Limited | Professional & scientific | 1999 |
| Red Balloon Consulting Ltd | Extraterritorial | 2022 |
| Red Camera Studio Ltd | Professional & scientific | 2007 |
| Red FOX Carpentry and Construction Ltd | Construction | 2019 |
| Red Gold 585 Ltd | Manufacturing | 2017 |
| Red Havas Limited | Professional & scientific | 2019 |
| Red House Properties LLP | | 2014 |
| Red Oak Garage Limited | Wholesale & retail | 2004 |
| Red Reform Ltd | Wholesale & retail | 2021 |
| Red Robin Property Management Limited | Real estate | 2025 |
| Red Songs Limited | Information & communication | 2001 |
| RED24 Ltd | Real estate | 2026 |
| RED3 Networks Ltd | Professional & scientific | 2024 |
| Redbud Partners Ltd | Professional & scientific | 2018 |
| Redcoast Property Developments Ltd | Construction | 2022 |
| Redcroft Fire Detection Limited | Extraterritorial | 2006 |
| Redcroft Fire Ltd | Construction | 2002 |
| Redcroft Fire Maintenance Limited | Extraterritorial | 2012 |
| Redesignr Ltd | Professional & scientific | 2025 |
| Redhill Farm Estate Ltd. | Agriculture & fishing | 2015 |
| Redlynch Residential Home Limited | Health & social care | 2002 |
| Redon Consulting Ltd | Administrative & support | 2009 |
| Redorbit Limited | Professional & scientific | 2022 |
| Redsky Aviation Services Limited | Manufacturing | 2025 |
| Redso Ltd | Wholesale & retail | 2021 |
| Redstart Inn Ltd | Hospitality | 2012 |
| Redtea Ltd | Information & communication | 2015 |
| Redtree Estates Ltd | Real estate | 2024 |
| Redwing Building Contractors Ltd | Construction | 2018 |
| Reece News Limited | Administrative & support | 2016 |
| Reedbase Limited | Households | 1989 |
| Reefermech Limited | Manufacturing | 2026 |
| Reel 2 Reel Films Ltd | Information & communication | 2019 |
| Reeve & Sons Limited | Construction | 2011 |
| Reeves & Co. Law Limited | Professional & scientific | 2004 |
| Reeves & Co. Solicitors Limited | Professional & scientific | 2008 |
| Reeves Commercial Property Limited | Real estate | 2026 |
| Reeves Estates Group Company Limited | Real estate | 2026 |