| Raven Blue Trading Ltd | Wholesale & retail | 2020 |
| RAY Hatten Ltd | Information & communication | 2016 |
| RAY ZAY Solutions Limited | Information & communication | 2008 |
| Rays Healthcare Ltd | Administrative & support | 2024 |
| Rayyan AK Homes Ltd | Real estate | 2024 |
| Rayza Appleton Ltd | Other services | 2025 |
| RB Building & Electrical Contractors Limited | Construction | 2014 |
| Rbir Properties Ltd | Real estate | 2021 |
| RC Consulting Services Ltd | Health & social care | 2016 |
| RCA Project Management Services Limited | Professional & scientific | 2018 |
| Rcbb Properties Ltd | Real estate | 2020 |
| Rccg Treasure House of GOD | Other services | 2010 |
| RCR Cleaners and Recruitment Ltd | Administrative & support | 2023 |
| RDH Property Ltd | Real estate | 2025 |
| RDL Infrastructure Ltd | Construction | 2026 |
| RDS Builders Ltd | Construction | 2025 |
| RE Flooring Ltd | Construction | 2024 |
| RE Kabira Ltd | Real estate | 2019 |
| Re:New Beauty Ltd | Wholesale & retail | 1998 |
| React Plant Supplies Limited | Administrative & support | 2003 |
| REACT4 Ltd | Construction | 2017 |
| Ready and Clean Limited | Administrative & support | 2025 |
| Real Hammer Limited | Transport & logistics | 2022 |
| Real Software Solutions Limited | Wholesale & retail | 2020 |
| Real Time Payroll Solutions Limited | Administrative & support | 2020 |
| Reald Europe Limited | Administrative & support | 2008 |
| Realfit VR Ltd | Information & communication | 2020 |
| Realm Associates Limited | Real estate | 2002 |
| Realmuto Building Services Ltd | Administrative & support | 2018 |
| Realmway Limited | Construction | 2007 |
| Reason Gaming Ltd | Arts & recreation | 2019 |
| Reba One Consultancy Ltd | Health & social care | 2012 |
| Rebbeck Limited | Real estate | 2009 |
| Rebel Beauty Brands Limited | Wholesale & retail | 2016 |
| Rebellion Management Company Limited | Households | 2004 |
| Recordati Pharmaceuticals Limited | Wholesale & retail | 2005 |
| Recordati UK Ltd | Wholesale & retail | 2014 |
| Rectory Farm at Grantham Managing Company Limited | Professional & scientific | 2023 |
| Red & Blue Air Conditioning Ltd | Construction | 2024 |
| Red 12 Recruitment Ltd | Administrative & support | 2021 |
| Red Beetle Marketing & Events Limited | Professional & scientific | 2015 |
| Red BUS Movies Limited | Information & communication | 2021 |
| Red DOT Reservoir and Land Conservation Limited | Professional & scientific | 2026 |
| Red DOT Security Limited | Administrative & support | 2020 |
| Red Edition Limited | Transport & logistics | 2016 |
| Red Geranium Accountancy Services Ltd | Professional & scientific | 2015 |
| Red Kite Telecommunications Ltd | Information & communication | 2016 |
| Red Lion Hospitality Ltd | Hospitality | 2025 |
| Red Robin Services Ltd | Professional & scientific | 2022 |
| Red Squirrel Brewery Limited | Manufacturing | 2010 |
| Red Squirrel Group Limited | Financial services | 2015 |
| Redbourn Park Group Ltd | Education | 2020 |
| Redcliff MGT Ltd | Arts & recreation | 2016 |
| Redfit Ltd | Wholesale & retail | 2015 |
| Redington Overseas Limited | Professional & scientific | 2007 |
| Rediscipline Ltd | Arts & recreation | 2020 |
| Redki Ltd | Professional & scientific | 2023 |
| Redlands Grange (Emsworth) Management Limited | Households | 2014 |
| Redserve Electrical Ltd | Financial services | 2025 |
| Redsky IT (Crick) Limited | Information & communication | 1992 |
| Redsky IT (Hemel) Limited | Information & communication | 1975 |
| Redsky IT Holdings Limited | Administrative & support | 1998 |
| Redstocks Ltd | Construction | 2021 |
| Redz Bar Ltd | Hospitality | 2016 |
| Reekhaye Investments Limited | Real estate | 2017 |
| Reel Lighting Ltd | Arts & recreation | 2026 |
| Reengineered Ltd | Professional & scientific | 2025 |
| Reeves Mews Parking Ltd | Financial services | 2024 |
| Refined Solutions UK Limited | Information & communication | 2017 |
| Reflections 2 (Colchester) Residents Company Limited | Households | 2012 |
| Reflections Residents Limited | Households | 2016 |
| Reflexion Associates Limited | Professional & scientific | 2009 |
| Refresh Panty | Manufacturing | 2019 |
| Regal Estates Ltd | Real estate | 2020 |
| Regal Renov UK Limited | Construction | 2024 |
| Regal Valley Homes Ltd | Households | 2025 |
| Regency Builders Ltd | Construction | 2011 |
| Regenerative Mind Ltd | Manufacturing | 2024 |
| Regent Build Works Limited | Manufacturing | 2025 |
| Regent Capital Communications Limited | Other services | 2013 |
| Regents Court Bishops Stortford Management Company Limited | Households | 2016 |
| Regis Park (Earley) Residents Management Company Limited | Households | 2008 |
| Regulation (GB) Limited | Wholesale & retail | 2007 |
| Reichle + DE Massari (UK) Limited | Other services | 1987 |
| Reimagine Property Ltd | Real estate | 2024 |
| REJ Group Limited | Transport & logistics | 2016 |
| Rejuvenate First AID Ltd | Education | 2026 |
| Rejuvenate Mental Health Ltd | Education | 2022 |
| Reliant Strategy Ltd | Real estate | 2025 |
| Remediation Waste Management Services Ltd | Water & waste | 2019 |
| Remia Ltd | Wholesale & retail | 2021 |
| Remikhart Ltd | Wholesale & retail | 2023 |
| Remo Deco Ltd | Construction | 2026 |
| Remo Travel & Tours Ltd | Administrative & support | 2023 |
| Remote Assistance Limited | Information & communication | 2017 |
| Remote Possibility Ltd | Administrative & support | 2026 |
| Rencon Ltd. | Construction | 2015 |
| Rendang Ltd | Water & waste | 2015 |
| Renegade Pearls Ltd | Wholesale & retail | 2025 |
| Renmus & Co Ltd | Real estate | 2025 |