| R&Dk Business Solutions Ltd | Information & communication | 2022 |
| R-Kapsalon Kebab's UK Ltd | Hospitality | 2025 |
| R.A. Latta (Farms) Limited | Agriculture & fishing | 1977 |
| R.A.D Sure Heating Ltd | Administrative & support | 2010 |
| R.A.O Private Hire Ltd | Transport & logistics | 2022 |
| R.H.Topham & Sons Limited | Agriculture & fishing | 1960 |
| R.M. Fields International Limited | Administrative & support | 1997 |
| R.O.S. Property Services Ltd | Real estate | 2023 |
| R2 Kumpukkal Ltd | Health & social care | 2026 |
| R3 Polygon UK Ltd. | Construction | 1946 |
| R9 Asbestos Compliance Limited | Professional & scientific | 2019 |
| R9 Asbestos Removal Ltd | Administrative & support | 2024 |
| R9 Freelance Support Ltd | Administrative & support | 2021 |
| RA Engineering Ltd | Professional & scientific | 2023 |
| RA1 Enterprise Ltd | Professional & scientific | 2017 |
| Rabatins Rentals Ltd | Real estate | 2023 |
| Raby Consulting Limited | Information & communication | 2014 |
| Raby Farming Company Limited | Agriculture & fishing | 2011 |
| Racing Ahead Ltd | Information & communication | 2004 |
| Radcliffe & Rust Limited | Real estate | 2010 |
| Radcliffe & Rust Property Ltd | Real estate | 2021 |
| Radley B. Ltd | Construction | 2006 |
| Rafix&Sow Ltd | Transport & logistics | 2025 |
| RAJ Medical Consultancy Ltd | Real estate | 2015 |
| RAM Properties (Cambs) Ltd | Real estate | 2024 |
| Rampit Solutions Ltd | Professional & scientific | 2020 |
| Ramply Farming Limited | Agriculture & fishing | 2013 |
| Rampton Cultivations Limited | Agriculture & fishing | 1949 |
| Ramsey Barbers Ltd | Other services | 2024 |
| Ramsey Bouncers Ltd | Arts & recreation | 2024 |
| Ramsey Club Company Limited | Hospitality | 1922 |
| Ramsey Dental Limited | Health & social care | 2018 |
| Ramsey Glass & Glazing Ltd | Construction | 2012 |
| Ramsey Global Foods Ltd | Wholesale & retail | 2026 |
| Ramsey Grocery Shop Ltd | Wholesale & retail | 2019 |
| Ramsey Self Store Limited | Real estate | 2017 |
| Ramsey Traditional Butchers Limited | Wholesale & retail | 2022 |
| Ramsey Traditional Investment Ltd | Professional & scientific | 2025 |
| Ramsey Travels Ltd | Transport & logistics | 2024 |
| Ramseyweb Ltd | Other services | 2019 |
| Randolph Group Limited | Information & communication | 2014 |
| Ranis Healthcare Limited | Health & social care | 2019 |
| Raphael Anopa Ltd | Health & social care | 2022 |
| Rapid Diesel Services Ltd | Energy | 2025 |
| Rapleys (Commercial Property and Planning Consultants) Limited | Real estate | 1987 |
| Rapleys Aston Rose Limited | Real estate | 2022 |
| Rapleys Building Consultancy LLP | | 2021 |
| Rapleys Consultants Limited | Real estate | 2016 |
| Rapleys Healthcare LLP | | 2017 |
| Rapleys Limited Liability Partnership | | 2004 |
| Rapunzeled by Caitlin Ltd | Other services | 2025 |
| Ratio Consultancy Limited | Professional & scientific | 2016 |
| Ravdon Health Care Ltd | Health & social care | 2021 |
| Raveikis Ltd | Transport & logistics | 2019 |
| Raveley Limited | Wholesale & retail | 2026 |
| Rawnsley Accountants Limited | Professional & scientific | 2016 |
| Ray's Garage Limited | Wholesale & retail | 2006 |
| Raymond DE Launey Ltd. | Real estate | 2011 |
| Raysocial Solutions Ltd | Information & communication | 2025 |
| RB Golf Limited | Wholesale & retail | 2011 |
| RB Trucking Ltd | Transport & logistics | 2017 |
| Rbdomus Limited | Real estate | 2024 |
| RBR Active Limited | Health & social care | 2018 |
| Rccg Amazing Grace Huntingdon | Other services | 2011 |
| RCE Engineering Ltd | Professional & scientific | 2024 |
| RDR Aerospace Limited | Wholesale & retail | 2006 |
| RDS Cardiology Ltd | Health & social care | 2020 |
| RDS Properties Cambridge Limited | Real estate | 2024 |
| Re-Tech UK Limited | Manufacturing | 2003 |
| Readiness Consulting Limited | Professional & scientific | 2026 |
| Ready Eats Ltd | Manufacturing | 2019 |
| Real CAP Limited | Real estate | 2012 |
| Real Number Seven Limited | Information & communication | 2022 |
| Realtime Holdings Limited | Manufacturing | 2023 |
| Rebserve Limited | Professional & scientific | 2022 |
| Rebuildcare Limited | Public administration | 2022 |
| Recruit Expert Ltd | Administrative & support | 2022 |
| Rectory Farm(Hemingford)Limited | Agriculture & fishing | 1954 |
| Red Dolphin Consultants Ltd | Information & communication | 2012 |
| Red Energy Group Limited | Manufacturing | 2011 |
| Red Energy Limited | Extraterritorial | 2011 |
| Red Human Limited | Professional & scientific | 2018 |
| Red Kite Construction & Renovation Ltd | Construction | 2024 |
| Red Kite Media Ltd | Information & communication | 2026 |
| Red Lion Court Management Limited | Households | 1972 |
| Red Silk Capital Limited | Real estate | 2020 |
| Red Tile Wind Farm Trust Fund Ltd. | Financial services | 2007 |
| Redbrick Print Solutions LLP | | 2003 |
| Redgrave H Ltd | Real estate | 2024 |
| Redwing VA Ltd | Administrative & support | 2021 |
| Redwings Lodge (Birmingham) Limited | Hospitality | 2017 |
| Redwings Lodge (Herts) Limited | Hospitality | 2013 |
| Redwings Lodge (Midlands) Limited | Hospitality | 2015 |
| Redwings Lodge (Rutland) Limited | Hospitality | 2013 |
| Redwings Lodge (Solihull) Limited | Hospitality | 2018 |
| Redwings Lodge Limited | Hospitality | 2004 |
| Redwings Properties Limited | Hospitality | 2015 |
| Redwood Lodge Consultancy Limited | Professional & scientific | 2025 |
| Reece Agricultural Engineering Limited | Manufacturing | 2020 |
| Reed Star Care Ltd | Health & social care | 2023 |