| RCP INV Holdings Ltd | Financial services | 2023 |
| RCP Invest Ltd | Construction | 2022 |
| RCR Global Limited | Wholesale & retail | 2014 |
| RCT Counselling Space Ltd | Health & social care | 2025 |
| RCT London Limited | Wholesale & retail | 2020 |
| RD Eco Solutions Ltd | Construction | 2023 |
| RD Global Ltd | Information & communication | 2023 |
| RD Mechanical Systems Ltd | Construction | 2024 |
| RDA Engineering Ltd | Professional & scientific | 2022 |
| RDC Solution Ltd | Construction | 2025 |
| RDH Accountants Ltd | Professional & scientific | 2011 |
| RDH Plumbing and Heating Limited | Construction | 2018 |
| RDK Construction Services Limited | Information & communication | 2021 |
| RDM Construction Ltd | Construction | 2025 |
| RDM Works Ltd | Construction | 2019 |
| RDP London Limited | Professional & scientific | 2018 |
| RDP Newmans LLP | | 2010 |
| RDR Furnishing Limited | Real estate | 2025 |
| RDR Heritage Ltd | Real estate | 2025 |
| RDR Ventures Limited | Real estate | 2018 |
| RDS Care Ltd | Health & social care | 2010 |
| RDS Resources Limited | Construction | 2020 |
| Rdvp UK Limited | Wholesale & retail | 2015 |
| Re-Fin Legal Consultants Ltd | Financial services | 2015 |
| Reach Accountants and Management Analysts Ltd. | Professional & scientific | 2017 |
| Reach Active Group Limited | Construction | 2005 |
| Reach Active Infrastructure Limited | Construction | 2007 |
| Reach Active Properties Limited | Real estate | 2004 |
| Reach Care Holdings Limited | Financial services | 2020 |
| Reach OUT Plumbing & Services Ltd | Construction | 2022 |
| Reactional Music UK Ltd | Arts & recreation | 2020 |
| Reading Construction Group Ltd | Construction | 2026 |
| Reading Corporate Limited | Real estate | 2018 |
| Ready Repairs & Maintenance Ltd | Construction | 2024 |
| Ready to Deliver Ltd | Administrative & support | 2007 |
| Real Construction Limited | Other services | 2010 |
| Real Dreams Consultancy Services Ltd | Education | 2011 |
| Real Health (NL) Limited | Health & social care | 2006 |
| Real Health (UK) Limited | Health & social care | 2003 |
| Real Life Care Ltd | Health & social care | 2011 |
| Real London Estates Ltd | Real estate | 2022 |
| Real Pharma Solutions Ltd | Wholesale & retail | 2020 |
| Realised Software Limited | Professional & scientific | 2011 |
| Reall Invest Ltd | Hospitality | 2019 |
| Really Wild Publishing Co Limited | Wholesale & retail | 2008 |
| Realmcraft Ltd | Professional & scientific | 2010 |
| Realrippers (Colindale) Ltd | Hospitality | 2021 |
| Realrippers Ltd | Hospitality | 2018 |
| Realtime DC Ltd | Information & communication | 2003 |
| Realty Invest Ltd | Real estate | 2023 |
| Reamaton Ltd | Wholesale & retail | 2023 |
| Rear 10 Effingham Ltd | Construction | 2024 |
| Reas Trade Ltd | Wholesale & retail | 2009 |
| Reassist Limited | Professional & scientific | 2019 |
| Reaval World Limited | Water & waste | 2022 |
| Rebel Camco Ltd | Wholesale & retail | 2025 |
| Rebel Rebel Hub Ltd | Professional & scientific | 2024 |
| Rebel Rebel Investments Ltd | Financial services | 2022 |
| Rebel Rebel Power Brands Ltd | Other services | 2024 |
| Rebi Trans Limited | Transport & logistics | 2019 |
| Rebmar Ltd | Construction | 2025 |
| Rebul UK Ltd | Manufacturing | 2019 |
| Recall Publishing Ltd | Information & communication | 2022 |
| Recirc Limited | Manufacturing | 2025 |
| Reckless EGO Ltd | Wholesale & retail | 2021 |
| Reco Medical Ltd | Professional & scientific | 2019 |
| Recons Civil Ltd | Construction | 2024 |
| Recoverie UK Limited | Health & social care | 2023 |
| Recovery for ALL Ltd | Transport & logistics | 2025 |
| Recovery International Ltd | Transport & logistics | 2020 |
| Recoverymen Limited | Transport & logistics | 2006 |
| Recreate Beauty Limited | Other services | 2022 |
| Recruit UNO Limited | Information & communication | 2025 |
| Red and Gold Limited | Arts & recreation | 2026 |
| Red Arowana Limited | Administrative & support | 2021 |
| Red Aura Trading Ltd | Wholesale & retail | 2025 |
| Red Blossom Properties Ltd | Real estate | 2021 |
| Red Brick UK Properties Ltd | Real estate | 2015 |
| Red Cannon Games Ltd | Manufacturing | 2024 |
| Red Car Parts Ltd | Water & waste | 2026 |
| Red Cherry Properties Ltd | Real estate | 2013 |
| Red Chilli Production Limited | Wholesale & retail | 2025 |
| Red Elephant Properties Limited | Real estate | 2023 |
| Red Ents Limited | Arts & recreation | 2015 |
| Red Event Logistics Limited | Arts & recreation | 2014 |
| Red Farm London Ltd | Hospitality | 2016 |
| Red Giant Films Ltd | Information & communication | 2026 |
| Red Health Ltd | Education | 2023 |
| Red Hot Goods Ltd | Manufacturing | 2025 |
| Red House Care Home (MM) Ltd | Health & social care | 2024 |
| Red Key Properties Ltd | Real estate | 2019 |
| Red Lester Pictures Ltd | Arts & recreation | 2025 |
| Red Macaw Ltd | Administrative & support | 2016 |
| Red MUD Capital Ltd | Financial services | 2011 |
| Red Ocean International Limited | Professional & scientific | 2017 |
| Red Ocean Limited | Hospitality | 2017 |
| Red Ochre Enterprises Limited | Professional & scientific | 2004 |
| Red Ochre Limited | Professional & scientific | 2012 |
| Red PIG Limited | Extraterritorial | 2015 |
| Red Python Limited | Hospitality | 2015 |