| Robine Limited | Information & communication | 2017 |
| Robins Barbers Ltd | Other services | 2026 |
| Robinson & Hall (Surveyors) Limited | Extraterritorial | 1986 |
| Robinson & Hall LLP | | 2004 |
| Robinson College (Cambridge) Management Training Limited | Professional & scientific | 1997 |
| Robinson Wiles Ltd | Construction | 2021 |
| Roblea Classic Engineering Company Limited | Professional & scientific | 2006 |
| Robot Industries Ltd | Manufacturing | 2022 |
| Robot Property Management LLP | | 2010 |
| Robotic Agents Ltd | Information & communication | 2023 |
| Robsonking Ltd | Professional & scientific | 2016 |
| Roca Fellas Ltd | Professional & scientific | 2025 |
| Roca Restaurant Ltd | Hospitality | 2022 |
| Rocco's Limited | Hospitality | 2013 |
| Rock Markets International Ltd | Real estate | 2019 |
| Rock of Ages Conglomerates UK Ltd | Agriculture & fishing | 2022 |
| Rock Realty Limited | Real estate | 2024 |
| Rockit Holdings Ltd | Real estate | 2024 |
| Rockit Media Limited | Hospitality | 2018 |
| Rockstonne Ltd | Administrative & support | 2026 |
| Rocky Developments Ltd | Real estate | 2022 |
| Rocky Homes Ltd | Construction | 2022 |
| Roedean Ltd | Households | 2004 |
| Roetta Logistics Limited | Transport & logistics | 2024 |
| Rogers of Bedford Limited | Wholesale & retail | 1993 |
| Roguard Ltd | Transport & logistics | 2025 |
| Rollback Roller Skating Ltd | Wholesale & retail | 2022 |
| Rollback World CIC | Wholesale & retail | 2023 |
| Rollei Films Ltd | Information & communication | 2024 |
| Rollo Art Limited | Arts & recreation | 2023 |
| Rolly H Decor INT Limited | Construction | 2025 |
| Roman Bathrooms Ltd | Construction | 2023 |
| Roman Paddock (Management) Limited | Households | 2015 |
| Roman Production Design Ltd | Professional & scientific | 2024 |
| Romanesc Limited | Wholesale & retail | 2015 |
| Romanian Gros Ltd | Wholesale & retail | 2025 |
| Romanin Food Express Ltd | Wholesale & retail | 2026 |
| Romeland Interiors Limited | Professional & scientific | 2015 |
| Romeo Dance Academy Limited | Education | 2014 |
| Roni Car Valeting Centre Ltd | Real estate | 2012 |
| Ronkets Ltd | Professional & scientific | 2024 |
| Roofline Systems (UK) Ltd | Construction | 2017 |
| ROOM2VIEW Limited | Real estate | 2022 |
| Root Properties Limited | Real estate | 2014 |
| Rootrise Landscapes Ltd | Administrative & support | 2024 |
| Rootz Consulting Limited | Information & communication | 2017 |
| Rope Access London Solutions Ltd | Construction | 2021 |
| Rosa Care Ltd | Health & social care | 2020 |
| Rosado Limited | Wholesale & retail | 2024 |
| Rosbo Ltd | Construction | 2020 |
| Roschainze-Ro Limited | Professional & scientific | 1989 |
| Rosco Risk Management Ltd | Financial services | 2021 |
| Rose & Crown Ashdon Ltd | Hospitality | 2024 |
| Rose & Ribbons UK Limited | Wholesale & retail | 2025 |
| Rose & Sons Capital Group Ltd | Real estate | 2024 |
| Rose Consult Limited | Professional & scientific | 2025 |
| Rose Court Management Company Limited | Households | 1985 |
| Rose Hill People & Organisation Development Limited | Other services | 2005 |
| Rose OWL Psychology Services Ltd | Education | 2023 |
| Roseheart Jewels Limited | Wholesale & retail | 2017 |
| Roselog Residents Association Limited | Households | 1983 |
| Rosiak Transport Ltd | Transport & logistics | 2016 |
| Rossam Limited | Professional & scientific | 2013 |
| Rossdata Services Limited | Professional & scientific | 1981 |
| Rossi Holdings Limited | Real estate | 2020 |
| Rostrum JIU Jitsu Ltd | Arts & recreation | 2018 |
| Rotatrim International Limited | Professional & scientific | 2000 |
| Rotatrim Limited | Manufacturing | 1959 |
| Rothdell Import/Export Limited | | 1992 |
| Rothery Rentals Ltd | Real estate | 2020 |
| Rothesay House Ltd | Hospitality | 2023 |
| Rothsay Locations Limited | Real estate | 2025 |
| Roughs Tower Films Ltd | Information & communication | 2025 |
| Rousbury Building Company Ltd | Construction | 2024 |
| Route One Recruitment Services Ltd | Professional & scientific | 2024 |
| Routetrip USA Ltd | Administrative & support | 2018 |
| Routh Properties Limited | Real estate | 2022 |
| ROW One Media Ltd | Professional & scientific | 2025 |
| Rowan-Baird Ltd | Professional & scientific | 2023 |
| Rowe's Sports and Academic Services Ltd | Education | 2025 |
| Rowington Management Solutions Ltd | Information & communication | 2019 |
| Rowland Charles Goodman Ltd | Public administration | 2011 |
| Roxton Bistro Ltd | Hospitality | 2026 |
| ROY Parry Associates Limited | Wholesale & retail | 2006 |
| Royaal Grill & Sweets Limited | Hospitality | 2016 |
| Royale Personnel Ltd | Education | 2019 |
| Royce Premier Ltd | Other services | 2021 |
| Royles AI Ltd | Manufacturing | 2025 |
| Roylt Aerospace Ltd | Extraterritorial | 2023 |
| Royston Court Residents Company (Potton) Limited | Households | 1977 |
| Royston Holdings Limited | Financial services | 2016 |
| RP Sharma and Sons Limited | Real estate | 2020 |
| Rp-X Fitness Limited | Administrative & support | 2017 |
| Rp-X Health Limited | Administrative & support | 2017 |
| Rp-X Services Limited | Administrative & support | 2018 |
| Rp-X Wellness Limited | Administrative & support | 2017 |
| RP3 Ltd | Other services | 2019 |
| RPA Aviation Ltd | Manufacturing | 2019 |
| RPA82 Properties Ltd | Real estate | 2022 |
| RPJ Emarketing Ltd. | Information & communication | 2012 |