| Radiro Ltd | Real estate | 2022 |
| Rainbow Conference Sets Ltd | Professional & scientific | 2011 |
| Rainbow Umbrella Services Ltd | Health & social care | 2013 |
| Rainmaker Energy Holdings UK Ltd | Construction | 2015 |
| Rainmaker Renewables Gamma Ltd | Construction | 2017 |
| Raja Holdings Limited | Real estate | 2007 |
| RAM Electrical Services Group Limited | Construction | 2020 |
| RAM Handyman Ltd | Construction | 2020 |
| Ramps 3 Ltd | Wholesale & retail | 2024 |
| Ranite Group Limited | Hospitality | 2026 |
| Rare Together Ltd | Professional & scientific | 2025 |
| Rarevale Limited | Real estate | 1983 |
| Raspberry Rentals Limited | Real estate | 2015 |
| Rather Clever Solutions Limited | Information & communication | 2023 |
| Razin LV Ltd | Hospitality | 2024 |
| RBI Tattoos Ltd | Arts & recreation | 2021 |
| RBO Creative Ltd | Wholesale & retail | 2026 |
| RCB Logic Limited | Wholesale & retail | 2009 |
| RCL Connectors & Cables Limited | Wholesale & retail | 2005 |
| RDS Security Limited | Extraterritorial | 2024 |
| RDS Security Services Limited | Extraterritorial | 2023 |
| Reactive Parts Limited | Administrative & support | 2013 |
| Read Electrical and Building Services Ltd | Construction | 2017 |
| Real Coffee With Benefits Limited | Professional & scientific | 2026 |
| Recoverly Ltd | Information & communication | 2025 |
| RECRE8 Collective Ltd. | Professional & scientific | 2025 |
| Recycled Products Limited | Water & waste | 2001 |
| Red Brick Publishing Solutions Limited | Information & communication | 2022 |
| Red Cloud Consulting Ltd | Information & communication | 2014 |
| Red Kite Advisory Limited | Professional & scientific | 2023 |
| Red Kite Schools Trust | Education | 2011 |
| Red Legal Practice Management Ltd | Professional & scientific | 2024 |
| Red Lighthouse Consultancy Limited | Professional & scientific | 2023 |
| Red Rose Chesham Ltd | Hospitality | 2025 |
| Red SPV Limited | Real estate | 2022 |
| Red Visual Effects Ltd | Information & communication | 2019 |
| Redding & Webb Limited | Construction | 1945 |
| Rediscover Your Relevance Ltd | Administrative & support | 2025 |
| Reeves Lawson & Co Law Limited | Professional & scientific | 2023 |
| Ref-Tec Ltd | Other services | 2025 |
| Refine Aesthetics Limited | Wholesale & retail | 2025 |
| Relaay Limited | Professional & scientific | 2025 |
| Reliablewares Ltd | Wholesale & retail | 2024 |
| Relyon Cars and Mini Buses Ltd | Transport & logistics | 2014 |
| Remeny Armitage Ltd | Other services | 2017 |
| Renrish Estates Limited | Administrative & support | 2025 |
| Renteq Highways Limited | Administrative & support | 2012 |
| Renteq Holding Company Limited | Financial services | 2025 |
| Rentex Ltd | Real estate | 2026 |
| Reseller Accounting Ltd | Professional & scientific | 2023 |
| Residents Management (NO. 76) Limited | Real estate | 1986 |
| Resolute Dog Security Limited | Administrative & support | 2020 |
| Resolve Optics Limited | Manufacturing | 2002 |
| Restore Hope | Other services | 2002 |
| Restore Hope Latimer | Extraterritorial | 2014 |
| Retirement Postponed CIC | Information & communication | 2018 |
| Retold Art Ltd | Wholesale & retail | 2023 |
| Revenuerise Ltd | Professional & scientific | 2023 |
| Reviewoptic Limited | Information & communication | 2026 |
| REX Advertising Limited | Professional & scientific | 2003 |
| REX Flat 1 Limited | Real estate | 2023 |
| REX Flat 2 Limited | Real estate | 2023 |
| REX Structures Limited | Real estate | 2022 |
| Reynard Entertainment Ltd | Information & communication | 2013 |
| Reza Construction Ltd | Construction | 2021 |
| RF Renewables Ltd | Construction | 2025 |
| RGV Multiservices Ltd | Administrative & support | 2015 |
| RGW Design Innovations Limited | Manufacturing | 2011 |
| Rhino Mobile Bar Systems Ltd | Administrative & support | 2016 |
| RI7 Limited | Information & communication | 2024 |
| Ribcage Cinema Products Ltd | Administrative & support | 2024 |
| Rich Construction Limited | Construction | 2018 |
| Rich Inks IT Limited | Wholesale & retail | 2012 |
| Rich Procurement Limited | Other services | 2018 |
| Rich Resources (UK) Limited | Professional & scientific | 2012 |
| Richard Birch & Company Limited | Wholesale & retail | 2024 |
| Richard Curtis Decorators Limited | Construction | 2016 |
| Richard Williams Cabinetmaker Ltd | Manufacturing | 2026 |
| Richings Park (Iver) Management Company Limited | Extraterritorial | 2015 |
| Rick English Stunts Limited | Information & communication | 2009 |
| Ridgeway Cars Ltd | Wholesale & retail | 2025 |
| Ridgeway Surveys Limited | Professional & scientific | 2012 |
| Right Maintenance Limited | Administrative & support | 2004 |
| Right Way Communications Ltd | Professional & scientific | 2023 |
| Rilep Ltd | Real estate | 2024 |
| Ringham Holdings Limited | Financial services | 2026 |
| Ringham Myers Construction Group Limited | Construction | 2026 |
| RISE8 Productions Ltd | Information & communication | 2026 |
| Rising Sun PVT Ltd | Financial services | 2023 |
| Rivergate House Residents Association Limited | Professional & scientific | 1994 |
| Riverside Publishing Limited | Information & communication | 2018 |
| RJ Haveli Limited | Real estate | 2017 |
| Rjes Consulting Ltd | Administrative & support | 2017 |
| RJK IT Consulting Limited | Information & communication | 2016 |
| RJL Heating & Plumbing Ltd | Construction | 2019 |
| RK Creative Consultancy Limited | Professional & scientific | 2017 |
| RKN Trading Services UK Ltd | Professional & scientific | 2019 |
| RMK Project Solutions Limited | Professional & scientific | 2017 |
| Road Warriors HQ Limited | Wholesale & retail | 2024 |
| ROB Eckland Music Ltd | Arts & recreation | 2012 |