| Rawability C.I.C. | Information & communication | 2021 |
| Raws BMS Limited | Wholesale & retail | 2022 |
| RAY Petty Meccanica Limited | Wholesale & retail | 2026 |
| Rayaanfurniture Ltd | Wholesale & retail | 2019 |
| Raylo Productions Ltd | Arts & recreation | 2020 |
| Rayne Gardens Management Company Limited | Households | 2018 |
| Rayner Properties Limited | Real estate | 2013 |
| Rayyan Global Investments Limited | Financial services | 2025 |
| RB Art & Conservation LLP | | 2019 |
| RB Nanny and Childcare Services Ltd | Health & social care | 2026 |
| RB Property Development Limited | Construction | 2007 |
| RBR Contracts Limited | Construction | 2015 |
| RC Technology Limited | Information & communication | 2010 |
| Rccg Redemption House Parish Manachester CIC | Health & social care | 2025 |
| Rccg- the New Creation Chapel for ALL Nations | Other services | 2024 |
| RCK Cars Ltd | Wholesale & retail | 2026 |
| RCM One Limited | Administrative & support | 2014 |
| RCM Publishing Ltd | Information & communication | 2020 |
| RCS General Contractors Ltd | Construction | 2016 |
| RD Fenner Services Limited | Administrative & support | 2018 |
| RD Media Limited | Professional & scientific | 2022 |
| Rdani Care Limited | Health & social care | 2021 |
| RDG 1971 Limited | Professional & scientific | 2007 |
| RDI Evolve Limited | Information & communication | 2022 |
| RDK Building Construction Limited | Construction | 2025 |
| Rdki Group Limited | Financial services | 2020 |
| RDN Contractors Ltd | Construction | 2024 |
| RDR Design Ltd | Professional & scientific | 2024 |
| RDS Property Group Limited | Real estate | 2024 |
| Rdss Reinforcement Ltd | Construction | 2017 |
| REA Ltd | Health & social care | 2023 |
| REA Wilson Limited | Administrative & support | 2021 |
| React Business Services Ltd | Professional & scientific | 2012 |
| React Secretarial Services Ltd | Administrative & support | 2020 |
| Reading West Aparthotel Limited | Hospitality | 2016 |
| Reading West Development Limited | Construction | 2016 |
| Ready to GLO Ltd | Other services | 2023 |
| READY4U Ltd | Construction | 2025 |
| Real Chauffeurs Limited | Transport & logistics | 2023 |
| Real Digital International Limited | Manufacturing | 2004 |
| Real Estate Business Services Limited | Information & communication | 2017 |
| Real FC Limited | Arts & recreation | 2008 |
| Real Flavour Caribbean Takeaway Ltd | Hospitality | 2015 |
| Real Steppaz Ltd | Manufacturing | 2025 |
| Real Taste of India (PVT) Ltd | Hospitality | 2022 |
| Real Transfers (Private) Limited | Administrative & support | 2015 |
| Real Transfers (UK) Limited | Administrative & support | 2014 |
| Real-Insight Consultants Ltd | Health & social care | 2022 |
| Realign Consulting (UK) Ltd | Information & communication | 2025 |
| Realise Digital Ltd | Information & communication | 2016 |
| Realstyle Ltd | Wholesale & retail | 2025 |
| Realta Project Management Limited | Professional & scientific | 2016 |
| Ream Projects LLP | | 2011 |
| Rebalance Limited | Professional & scientific | 2022 |
| Rebecca Court (Kenley) Management Company Limited | Households | 1999 |
| Rebecca Palmer Ltd | Health & social care | 2025 |
| Rebekah Kipps Ltd | Other services | 2013 |
| Rebirthuk Limited | Wholesale & retail | 2022 |
| Reborn Autos Ltd | Wholesale & retail | 2022 |
| Reborn Packaging Ltd | Administrative & support | 2023 |
| Rebound Healthcare Ltd | Health & social care | 2021 |
| Rebuild and Rebrand Ltd | Health & social care | 2020 |
| REC Builders Ltd | Construction | 2022 |
| Recalibrate Holistic Wellbeing Ltd | Education | 2023 |
| Recfair Ltd | Administrative & support | 2019 |
| Reclaim Yourself Retreats Ltd | Administrative & support | 2022 |
| Recolight Limited | Water & waste | 2005 |
| Reconfigure Ltd | Professional & scientific | 2022 |
| Recore Consultants Ltd | Professional & scientific | 2020 |
| Recovery Palace Ltd | Health & social care | 2022 |
| Recruitment Divisions Limited | Administrative & support | 2003 |
| Recycling Channel Limited | Wholesale & retail | 2022 |
| Red Bird Data Ltd | Financial services | 2021 |
| Red Brusk Ltd | Wholesale & retail | 2025 |
| Red Circle Security Services (Europe) Limited | Administrative & support | 1991 |
| Red Circle Security Services International Limited | Extraterritorial | 2003 |
| Red Circle Security Services Limited | Real estate | 1985 |
| Red Lion Freehold Limited | Households | 2016 |
| Red Phoenix Ventures Limited | Wholesale & retail | 2015 |
| Red Point Cleaning Service Limited | Households | 2016 |
| Red RAW Productions Limited | Information & communication | 2007 |
| Red Socks Press Ltd | Information & communication | 2021 |
| Red Telephone Limited | Professional & scientific | 2017 |
| Red Tusker Ltd | Construction | 2015 |
| Red Valley Limited | Wholesale & retail | 2019 |
| Red White Rose Limited | Wholesale & retail | 2003 |
| Red Wing Media Limited | Administrative & support | 2007 |
| Redana Limited | Extraterritorial | 2004 |
| Reddoor IT Ltd | Information & communication | 2010 |
| Reddoor Money Limited | Information & communication | 2012 |
| Reddy Consultancy Services Ltd | Information & communication | 2012 |
| Redeemed Christian Church of GOD, Faith & Holiness Centre | Other services | 2013 |
| Redhilllogistics Limited | Transport & logistics | 2025 |
| Redit Limited | Real estate | 2001 |
| Redland Court Ltd | Households | 2020 |
| Redlaw Consultants Limited | Professional & scientific | 2018 |
| Redline Music Ltd | Information & communication | 2021 |
| Redmonds Property Rentals Ltd | Real estate | 2023 |
| Redstart Consultancy Ltd | Information & communication | 2019 |
| Redthread Consulting and Coaching Ltd | Information & communication | 2025 |