| R.Havens Limited | Wholesale & retail | 1950 |
| R.J.S. Testing Services Ltd | Professional & scientific | 2022 |
| R.O.A.M Contractors Ltd | Construction | 2021 |
| R13 Ltd | Information & communication | 2022 |
| RAA Development Group Ltd | Construction | 2018 |
| Rachael Leigh Johnson Limited | Public administration | 2024 |
| Racon Investments Limited | Hospitality | 2020 |
| Racon Trading Limited | Hospitality | 2020 |
| RAD Catering Limited | Hospitality | 2021 |
| Radiant Media Group Limited | Professional & scientific | 2025 |
| Radley Automations Limited | Professional & scientific | 2018 |
| Radnoel Limited | Extraterritorial | 2012 |
| RAE & Tate Ltd | Real estate | 2021 |
| RAF Consultants Limited | Administrative & support | 2026 |
| Rafael Pacheco Limited | Administrative & support | 2015 |
| Rafaello's Ltd | Hospitality | 2022 |
| Rafiqan Limited | Health & social care | 2015 |
| Rafique & Co Ltd | Professional & scientific | 2019 |
| Rahart Limited | Professional & scientific | 2007 |
| Rahima B Ltd | Real estate | 2022 |
| Rahisi Ltd | Wholesale & retail | 2017 |
| Rahma Coffee Limited | Hospitality | 2026 |
| Rail Ticketing Assets Limited | Administrative & support | 2013 |
| Railway TAV Ltd | Hospitality | 2018 |
| Raimax Investment Company Ltd | Financial services | 2012 |
| Rainbow Express Ltd | Wholesale & retail | 2021 |
| Rainbow Metro Limited | Health & social care | 2012 |
| Raja Boxing UK Limited | Manufacturing | 2025 |
| Raleigh Close Limited | Real estate | 1985 |
| RAM Trading Group Limited | Construction | 2020 |
| Ramkrishna General Trading Limited | Wholesale & retail | 2017 |
| Ramon Holdings Limited | Manufacturing | 2006 |
| Ramon Hygiene Products Limited | Extraterritorial | 2001 |
| Ramp Circle UK Limited | Real estate | 2020 |
| Rams Fish 27 Ltd | Hospitality | 2026 |
| Ranaissance Health Care Ltd | Health & social care | 2025 |
| Rang Apane Ltd | Wholesale & retail | 2025 |
| Rapid Lifeline EMS Ltd | Public administration | 2025 |
| Rapid Removals & Recoverys Ltd | Transport & logistics | 2026 |
| Rapid Transport Solutions Ltd | Transport & logistics | 2024 |
| Rapid Wheels Limited | Administrative & support | 2008 |
| Rapta Properties Ltd | Real estate | 2025 |
| Rascals Childcare Limited | Health & social care | 2004 |
| Raven ROW Traders Ltd | Other services | 2020 |
| RAW Learning Community C.I.C. | Education | 2020 |
| Rayleigh Glass Windows & Conservatories Limited | Construction | 1983 |
| Raynance Limited | Professional & scientific | 2024 |
| Rayzen Ltd | Health & social care | 2026 |
| RB Engineers Ltd | Professional & scientific | 2000 |
| RBA Payroll Services Ltd | Other services | 2023 |
| RBC Carpentry Limited | Construction | 2019 |
| RBM IT Solutions Limited | Information & communication | 2011 |
| RC Knight Limited | Professional & scientific | 2015 |
| RCG Utilities Limited | Energy | 2025 |
| RCW Consulting Ltd | Professional & scientific | 2022 |
| RD Kelly Consulting Ltd | Professional & scientific | 2021 |
| RD Property Group Limited | Real estate | 2025 |
| RD Property Management Limited | Real estate | 2008 |
| RDC Search Limited | Financial services | 2025 |
| RDS Property Limited | Real estate | 2000 |
| Rdsilva Ltd | Construction | 2018 |
| Reach OUT Care Services Limited | Health & social care | 2022 |
| Reaching New Heights CIC | Education | 2025 |
| Reactive Brands Ltd | Wholesale & retail | 2023 |
| Read the Cardboard Ltd | Wholesale & retail | 2022 |
| Readypeople Ltd | Information & communication | 2006 |
| Real Organisation Ltd | Wholesale & retail | 2023 |
| Realgemz Services Limited | Public administration | 2026 |
| Reap and SOW Gardening Limited | Administrative & support | 2016 |
| Reaven Holding (UK) Limited | Professional & scientific | 2011 |
| Reb-Tek-Research Limited | Professional & scientific | 2024 |
| Recho Ward Enterprises Ltd | Information & communication | 2022 |
| Reclaim Mobility Limited | Health & social care | 2024 |
| Recruit & People Services Ltd | Administrative & support | 2026 |
| Recycling Company Essex Limited | Water & waste | 2024 |
| Red Success Lane Holdings Limited | Real estate | 2018 |
| Red Success Lane Limited | Wholesale & retail | 2018 |
| Red Wilson Associates Limited | Professional & scientific | 2017 |
| Redact SAR Ltd | Information & communication | 2025 |
| Reddish Accountancy Services Limited | Professional & scientific | 2020 |
| Redhill Contractors Limited | Professional & scientific | 2022 |
| Redigitised Ltd | Information & communication | 2023 |
| Redlodge (Suffolk) Management Company Limited | Households | 2018 |
| Redram Technology Limited | Information & communication | 2016 |
| Redstock Clothing Limited | Wholesale & retail | 2022 |
| Redwood Tree Care and Services Ltd | Administrative & support | 2023 |
| Reed & Daughter Limited | Administrative & support | 2026 |
| Reed Energy Performance Consultancy Ltd | Administrative & support | 2020 |
| Reed Residential Lettings and Management Ltd | Construction | 2024 |
| Reehana Limited | Financial services | 2017 |
| Reform Property Services Ltd | Construction | 2026 |
| Rega Research Limited | Manufacturing | 1973 |
| Rega Trustees Limited | Professional & scientific | 2024 |
| Regency Gardens (Wath) Management Company Limited | Households | 2014 |
| Regency Gatehouse Limited | Real estate | 2018 |
| Regency Passive Fire Protection Limited | Public administration | 2011 |
| Regentcharm Limited | Extraterritorial | 2017 |
| Regis (Barclays) Holdings Limited | Professional & scientific | 2002 |
| Regis (Directors Nominee) Limited | Extraterritorial | 1999 |
| Regis (UBK) Holdings Limited | Professional & scientific | 2002 |