| Rcwm Group Ltd | Professional & scientific | 2018 |
| RD Group Services Ltd | Administrative & support | 2018 |
| RD Pharma Ltd | Professional & scientific | 2022 |
| RD Private Hire Ltd | Administrative & support | 2021 |
| RDC Roofing Limited | Construction | 2020 |
| RDJ Group Limited | Real estate | 2017 |
| RDJ Utilities Limited | Information & communication | 2015 |
| RDK & Banaras Property Ltd | Real estate | 2025 |
| RDM Traders Ltd | Wholesale & retail | 2025 |
| RDT Capital Investments Limited | Financial services | 2023 |
| RE Facilities Management Limited | Real estate | 2011 |
| Reach Ahead Media Ltd | Information & communication | 2026 |
| Reach Manpower Ltd | Administrative & support | 2021 |
| Reach Properties Ltd | Real estate | 2022 |
| Reach Property Venture Limited | Real estate | 2026 |
| Reachclients Ltd | Information & communication | 2026 |
| Reading Cosmetic Clinic Limited | Health & social care | 2017 |
| Ready II Move Ltd | Transport & logistics | 2019 |
| Ready to Leaning Ltd | Hospitality | 2015 |
| Real Capital Asset Limited | Real estate | 2017 |
| Real DAN Construction Ltd | Construction | 2020 |
| Real Edge Consultancy Limited | Information & communication | 2024 |
| Real Estate Connection Ltd | Hospitality | 2026 |
| Real Estate Portfolio Ltd | Real estate | 2017 |
| Real Estate Property Ltd | Real estate | 2021 |
| Real Time Construction Ltd | Construction | 2026 |
| Real Tokenization Ltd | Information & communication | 2025 |
| Real Vantage Ltd | Wholesale & retail | 2016 |
| Reality Management Services Limited | Professional & scientific | 2001 |
| Realmost Ltd | Administrative & support | 2009 |
| Realtimeseismic Limited | Professional & scientific | 2019 |
| Reanne’S Retreat Ltd | Real estate | 2025 |
| Reap Capital Advisory Ltd | Professional & scientific | 2024 |
| REB Logistics Ltd | Administrative & support | 2016 |
| Rebounce Place Limited | Health & social care | 2021 |
| Recaud Ltd | Information & communication | 2022 |
| Rechi’S Kitchen Ltd | Hospitality | 2024 |
| Recica Engineering Ltd | Manufacturing | 2017 |
| Reckless Law Ltd | Wholesale & retail | 2024 |
| Recruiture Growth Limited | Wholesale & retail | 2025 |
| Recsource Limited | Administrative & support | 2023 |
| Recycling With Skips Limited | Water & waste | 2010 |
| Red Apple Care Ltd | Health & social care | 2023 |
| Red Apple Logistics Ltd. | Administrative & support | 2012 |
| Red Envelopes Ltd | Wholesale & retail | 2023 |
| Red Feather Solutions (RFS) Ltd | Information & communication | 2023 |
| Red Light & Bell Productions Limited | Information & communication | 2024 |
| Red Line Motors Ltd | Wholesale & retail | 2016 |
| Red Mountain Estates Ltd | Real estate | 2023 |
| Red Nine Developments Limited | Real estate | 2019 |
| Red One Nutrition Ltd | Hospitality | 2022 |
| Red Panda Solutions Ltd | Transport & logistics | 2016 |
| Red Sky Group (Uk&I) Ltd | Administrative & support | 2023 |
| Red Sky Personnel Ltd | Administrative & support | 2020 |
| Red Sky Referencing Limited | Administrative & support | 2023 |
| Redacted Interactive Limited | Professional & scientific | 2025 |
| Redbox Finance Ltd | Financial services | 2024 |
| Redcroft London Ltd | Professional & scientific | 2020 |
| Reddi Limited | Transport & logistics | 2020 |
| Redditch Food Ltd | Hospitality | 2019 |
| Redefine and Future Construction Ltd | Construction | 2018 |
| Redlabeloutlet Limited | Wholesale & retail | 2012 |
| Redrock Fittings Ltd | Wholesale & retail | 2025 |
| Redrock Flooring Ltd | Wholesale & retail | 2023 |
| Redrose Worldwide Ltd | Manufacturing | 2025 |
| Reds Limited Partnership | | 2019 |
| Redtop 41 Limited | Wholesale & retail | 2025 |
| Redz Investments Ltd | Real estate | 2023 |
| Reed Security and Logistics Ltd | Administrative & support | 2024 |
| Reel Medic Ltd | Health & social care | 2019 |
| Reemskn Ltd | Other services | 2023 |
| Reemsrose Limited | Transport & logistics | 2024 |
| Reets Healthcare Services Ltd | Health & social care | 2023 |
| Reeva Mart Limited | Wholesale & retail | 2025 |
| Refaby Ltd | Wholesale & retail | 2025 |
| Reference Homes UK Limited | Real estate | 2017 |
| Refine Skinn Limited | Other services | 2024 |
| Refine Space Ltd | Construction | 2026 |
| Refined Air Ltd | Energy | 2025 |
| Refined Nutrition Ltd | Wholesale & retail | 2020 |
| Reflections Online Ltd | Wholesale & retail | 2018 |
| Reflections Property Ltd | Real estate | 2016 |
| Refumo Investments LP | | 2021 |
| Regal & General Limited | Administrative & support | 2009 |
| Regal Court Residents' Association Limited | Households | 1970 |
| Regal Exim Ltd | Wholesale & retail | 2019 |
| Regal Mobility Solutions Ltd | Transport & logistics | 2025 |
| Regal Rides Limited | Transport & logistics | 2021 |
| Regal Sounds Music Ltd | Arts & recreation | 2020 |
| Regal Travel Solutions Limited | Transport & logistics | 2006 |
| Regal Vehicle Detailing Ltd | Professional & scientific | 2016 |
| Regalia Enterprises Limited | Wholesale & retail | 2022 |
| Regantology Limited | Information & communication | 2017 |
| Regency Holdings SPV Ltd | Real estate | 2025 |
| Regent Street Management Services Limited | Households | 1995 |
| Regis Star & Co Ltd | Other services | 2016 |
| Regwork Consulting Limited | Professional & scientific | 2021 |
| Rehank Trading Ltd | Real estate | 2024 |
| REI DO Goias Lettings and Management Ltd | Real estate | 2024 |
| Rejuvenesse Ltd | Health & social care | 2020 |