| Reed Packaging Limited | Manufacturing | 1933 |
| Reed Thermoformed Packaging Ltd. | Manufacturing | 2016 |
| Reef International Limited | Professional & scientific | 2004 |
| Reel IT Leisure Limited | Hospitality | 2023 |
| Reemc & Co Limited | Real estate | 2026 |
| Reeves Business Services Limited | Information & communication | 2020 |
| Reeves Family Holdings Ltd | Financial services | 2026 |
| Reeves Financial Services Limited | Financial services | 1998 |
| Reeves Group Holdings Limited | Financial services | 2019 |
| Reeves Independent (Acquisitions) Limited | Financial services | 2020 |
| Reeves Independent Limited | Financial services | 2019 |
| Reeves Independent Property Limited | Real estate | 2022 |
| Reeves Independent Wills and Estate Planning Ltd. | Professional & scientific | 2013 |
| Reeves Investment Services Limited | Financial services | 2020 |
| Reeves Personal Investment Company Limited | Financial services | 2025 |
| Referee Consultant Ltd | Education | 2020 |
| Refine Gosforth Ltd | Other services | 2025 |
| Refine Solutions Limited | Information & communication | 2017 |
| Refined Beauty Academy Ltd | Education | 2025 |
| Refined Electricals Ltd | Construction | 2025 |
| Reflect to Rise Ltd | Education | 2024 |
| Reflex Academy Limited | Arts & recreation | 2010 |
| Reflexions Counselling & Psychotherapy Ltd | Health & social care | 2024 |
| Reform Studio Group Limited | Wholesale & retail | 2025 |
| Reformation Church Trust. | Other services | 1926 |
| Refresh Bathrooms Ltd | Construction | 2018 |
| Refresh Energy Limited | Professional & scientific | 2015 |
| Refreshingly Retro Limited | Manufacturing | 2019 |
| Refurbli Limited | Wholesale & retail | 2025 |
| Regal Munchies Ltd | Hospitality | 2025 |
| Regalstone Limited | Real estate | 2025 |
| Regan Solutions Ltd | Information & communication | 2022 |
| Regen Healthcare Limited | Wholesale & retail | 2016 |
| Regen Partner (UK Limited | Professional & scientific | 2023 |
| Regency Home Designs Ltd | Other services | 2018 |
| Regency Place (Chapelgarth) Management Company Limited | Real estate | 2024 |
| Regenerate Newcastle Asset Co Limited | Professional & scientific | 2018 |
| Regent Decorators Limited | Construction | 1983 |
| Regent Properties NE Limited | Real estate | 2026 |
| Regents Court (Darlington) Limited | Households | 1990 |
| Regio Group Limited | Other services | 2016 |
| Regional Group Limited | Administrative & support | 2025 |
| Registration and Support Services C.I.C. | Administrative & support | 2019 |
| Regland Limited | Information & communication | 2023 |
| Regnart Brothers Properties Limited | Real estate | 1985 |
| Regreen Community Interest Company | Manufacturing | 2023 |
| Regulate With Kate Ltd | Health & social care | 2026 |
| Rehaam Limited | Transport & logistics | 2022 |
| Rehan Lettings Ltd | Real estate | 2025 |
| Rehman Brothers Trading Ltd | Wholesale & retail | 2026 |
| Rehman Pharma Ltd | Wholesale & retail | 2025 |
| Rehman Properties Limited | Real estate | 2013 |
| Rehob'Th International Ltd | Wholesale & retail | 2025 |
| Reial Property Investments Limited | Real estate | 1947 |
| Reid Birkett Limited | Professional & scientific | 2014 |
| Reid Hackett Tax & Accountancy Limited | Professional & scientific | 2013 |
| Reid Surfacing Ltd | Construction | 2018 |
| Reigate Specialist Orthodontic Practice Ltd | Health & social care | 2013 |
| Reight Crosby Cleaning Ltd | Administrative & support | 2021 |
| Reight Travel Group Ltd | Administrative & support | 2019 |
| Reiver Flooring Limited | Construction | 2003 |
| Reiver Software Limited | Information & communication | 2023 |
| Rejuvenair Ltd | Manufacturing | 2020 |
| Rejuvi Wellness Ltd | Other services | 2026 |
| Rekendyke Mews Management Limited | Real estate | 2005 |
| Relaunch Collective Limited | Other services | 2025 |
| Relaxris Limited | Administrative & support | 2026 |
| Releaf Physiotherapy Ltd | Health & social care | 2016 |
| Relecy Investment Ltd | Real estate | 2015 |
| Relentless FOX Limited | Professional & scientific | 2019 |
| Reliability Training Lifecycle Global Consultants Ltd | Professional & scientific | 2025 |
| Reliable Waste Ltd | Water & waste | 2022 |
| Reliant Couriers Ltd | Transport & logistics | 2017 |
| Relocategy Ltd | Administrative & support | 2022 |
| Relopro Ltd | Real estate | 2023 |
| Reluctant Hero Limited | Extraterritorial | 2002 |
| REM Innovations Ltd | Professional & scientific | 2026 |
| REM Surgical Ltd | Health & social care | 2020 |
| Remaxyorkshire Ltd | Real estate | 2025 |
| Remedose Ltd | Public administration | 2025 |
| Remember Media Limited | Information & communication | 2011 |
| Remflo Design Ltd | Professional & scientific | 2025 |
| Remora Associates Ltd | Professional & scientific | 2025 |
| Remosc Ltd | Wholesale & retail | 2026 |
| Renderloft Limited | Professional & scientific | 2011 |
| Renegade Clothing Company Limited | Manufacturing | 2019 |
| Renew Electrics Limited | Construction | 2023 |
| Renewable Energy Solutions (RES) Limited | Wholesale & retail | 2020 |
| Renewable Resourcing Limited | Construction | 2024 |
| Renewable Technology Advice Ltd | Other services | 2025 |
| Renna Ltd | Wholesale & retail | 2022 |
| Rennolds Ltd | Education | 2019 |
| Renry Properties Limited | Real estate | 2021 |
| Rentbook Ltd | Information & communication | 2015 |
| Rentdesi Ltd | Administrative & support | 2025 |
| Renwick Flooring Limited | Construction | 2006 |
| Repoint Solutions Ltd | Construction | 2024 |
| Reptile Realm & Aquatics Limited | Administrative & support | 2017 |
| RES Inspection Limited | Professional & scientific | 2024 |
| Rescented Ltd | Wholesale & retail | 2025 |