| Ritoa and Co Limited | Health & social care | 2016 |
| River Consulting Ltd | Administrative & support | 2024 |
| River Front Properties Limited | Real estate | 1960 |
| River Kwai 2 Limited | Health & social care | 2022 |
| River Kwai Limited | Health & social care | 2018 |
| River Nine Consultancy Ltd | Professional & scientific | 2019 |
| Riverhay Limited | Wholesale & retail | 2025 |
| Riverton Trading Ltd | Wholesale & retail | 2025 |
| Riverwoodhousingsolutions Ltd | Real estate | 2026 |
| Riviera Car Services Ltd | Wholesale & retail | 2015 |
| Riviera Maritime Media Limited | Information & communication | 2001 |
| Rivulet Counselling and Psychotherapy Ltd | Health & social care | 2026 |
| RIX (UK) Limited | Construction | 1996 |
| RJ & KJ Consulting Limited | Transport & logistics | 2016 |
| RJ Empire Ltd | Administrative & support | 2025 |
| RJ Fabrication & Design Ltd | Manufacturing | 2019 |
| RJ Green Tree Ltd | Real estate | 2025 |
| RJ Rents Ltd | Real estate | 2023 |
| RJK Security Holdings Limited | Real estate | 2018 |
| RJM and Sons Limited | Real estate | 2001 |
| RJT Traffic Management and Traffic Marshall Ltd | Construction | 2024 |
| RK Trading UK Ltd | Wholesale & retail | 2017 |
| Rk's Foods Limited | Hospitality | 2025 |
| RK8 Limited | Real estate | 2017 |
| RKD Futures Ltd | Wholesale & retail | 2023 |
| Rkfg Holdings Ltd | Real estate | 2022 |
| Rkfg Property Limited | Real estate | 2023 |
| RKP Adventures Ltd | Real estate | 2023 |
| RLR Automotive Ltd | Wholesale & retail | 2025 |
| RMA Grow Ltd | Real estate | 2025 |
| RMB Facilities Ltd | Administrative & support | 2024 |
| RMC Plastering London Ltd | Construction | 2023 |
| Rmfilmmaker Productions Limited | Information & communication | 2015 |
| RMN 24/7 Care Support Limited | Administrative & support | 2013 |
| RMV Storage & Removals Limited | Wholesale & retail | 2013 |
| Rnbaby Limited | Hospitality | 2025 |
| RND Accountants Limited | Professional & scientific | 2013 |
| RNG PVT Limited | Hospitality | 2020 |
| RO Elite Transport Logistics Ltd | Transport & logistics | 2026 |
| RO Enterprises Ltd | Real estate | 2025 |
| Roacc Limited | Construction | 2011 |
| Road Star Hire Ltd | Administrative & support | 2025 |
| Roadways Transport Services Limited | Transport & logistics | 2022 |
| Roam Villa Ltd | Other services | 2025 |
| Roar and Explore Ltd | Administrative & support | 2025 |
| Roar Cacao Ltd | Wholesale & retail | 2025 |
| ROB Weller Design Limited | Professional & scientific | 2025 |
| ROB17TAT Ltd | Other services | 2018 |
| Robbins Candle Company Ltd | Manufacturing | 2019 |
| Roberant Ltd | Administrative & support | 2018 |
| Roberk Ltd | Wholesale & retail | 2019 |
| Robert Anthony Limited | Real estate | 1947 |
| Robert Mclachlan Limited | Professional & scientific | 2016 |
| Roberts Builders Ltd | Construction | 2016 |
| Robin Kendall and Co Limited | Professional & scientific | 2019 |
| Robin Martin Antiques Limited | Wholesale & retail | 2015 |
| Robu Group Ltd | Construction | 2026 |
| Robur.Virtus Limited | Professional & scientific | 2025 |
| Roburn Limited | Administrative & support | 2026 |
| Rocana Ltd | Health & social care | 2012 |
| Rock Driving School Ltd | Education | 2024 |
| Rocks Electrical Services Ltd | Construction | 2026 |
| Rodinik Limited | Hospitality | 2025 |
| Rodizio Rico Birmingham Limited | Hospitality | 2011 |
| Roen Builders Ltd | Construction | 2023 |
| Roger Bikes (Enfield) Ltd | Other services | 2023 |
| Rokai Capital Ltd | Wholesale & retail | 2022 |
| Roland House RTM Company Limited | Households | 2013 |
| Roljan Investments Limited | Extraterritorial | 2013 |
| Roma Bella Enfield Ltd | Hospitality | 2024 |
| Roma Global Ltd | Wholesale & retail | 2024 |
| Roma Joinery and Glazing Limited | Construction | 2013 |
| Roma Property Limited | Real estate | 2017 |
| Romaas Ltd | Construction | 2023 |
| Roman Kabab Ltd | Hospitality | 2019 |
| Romana 777 Ltd | Transport & logistics | 2019 |
| Romans Plumbing and Heating Ltd | Construction | 2025 |
| Rona Properties Ltd | Real estate | 2026 |
| Ronik Consulting & Training Ltd | Other services | 2012 |
| Ronirm Property Ltd | Construction | 2025 |
| Ronnoco (Properties) Limited | Construction | 1974 |
| Ronnoco Plant Limited | Administrative & support | 1987 |
| Roof Leak Experts Ltd | Construction | 2025 |
| Rooftop Rooms Limited | Construction | 2004 |
| Rook Developments Limited | Information & communication | 2025 |
| Rootone Consultancy Limited | Professional & scientific | 2026 |
| Rosa Electrical Ltd | Construction | 2018 |
| Rosa Retail Ltd | Wholesale & retail | 2024 |
| Rosbion Limited | Information & communication | 2007 |
| Rosco Construction Limited | Construction | 2023 |
| Rose -T Hair & Beauty Limited | Other services | 2020 |
| Rose Barber Ltd | Administrative & support | 2017 |
| Rose Estates & Lettings Ltd | Real estate | 2025 |
| Rose Fresh Foods Ltd | Wholesale & retail | 2025 |
| Rosebud Support Solutions Limited | Information & communication | 2018 |
| Rosecroft Consultants Ltd | Professional & scientific | 2016 |
| Rosei Nail Limited | Other services | 2024 |
| Roselight Care Limited | Health & social care | 2026 |
| Rosemary Auto Ltd | Wholesale & retail | 2025 |
| Rosenberg Construction and Metals Ltd | Manufacturing | 2026 |