| R.B. Aspirations Limited | Financial services | 2019 |
| RA (Chalfont) Ltd | Wholesale & retail | 2023 |
| RA Convery Limited | Financial services | 2010 |
| RA Creative Designs Limited | Administrative & support | 2021 |
| Rachel Davies Ltd. | Professional & scientific | 2012 |
| Radar Music Limited | Information & communication | 1977 |
| Radcot Construction and Groundworks Ltd | Other services | 2002 |
| Radcot Plumbing & Heating Limited | Construction | 2022 |
| Radhaa Enterprises Ltd | Real estate | 2026 |
| Radiant Barnet Limited | Real estate | 2017 |
| Radiant Broxbourne Limited | Real estate | 2014 |
| Radiant Harrow Limited | Real estate | 2017 |
| Radiant Harrow Weald Limited | Real estate | 2017 |
| Radiant Hatfield Limited | Real estate | 2015 |
| Radiant Isleworth Limited | Real estate | 2021 |
| Radiant Medicare Limited | Health & social care | 2008 |
| Radiant Productions Limited | Manufacturing | 1998 |
| Radiant Properties Limited | Real estate | 2016 |
| Radiant Residential Limited | Real estate | 2017 |
| Radiant South Harrow Limited | Real estate | 2015 |
| Radiant ST Albans Limited | Real estate | 2016 |
| Radiant Studios Limited | Information & communication | 2007 |
| Radiant Ware Limited | Construction | 2025 |
| Radiant Weald Limited | Real estate | 2019 |
| Radiant Wembley Limited | Real estate | 2012 |
| Radicare Limited | Wholesale & retail | 2015 |
| Radichem Limited | Wholesale & retail | 2024 |
| Radipharm Limited | Wholesale & retail | 2016 |
| Radius Estates Limited | Extraterritorial | 2012 |
| Radshaw Solicitors Limited | Professional & scientific | 2014 |
| Rafflescout Limited | Professional & scientific | 2026 |
| Raguso Real Estate Limited | Real estate | 2012 |
| Raindance Inc Limited | Wholesale & retail | 2016 |
| Randall Electrical Services Limited | Construction | 2003 |
| Randle Estates Limited | Real estate | 2018 |
| Raoul of London Holdings Limited | Financial services | 2014 |
| Rarissimaa Ltd | Wholesale & retail | 2022 |
| RAW Pictures Ltd | Information & communication | 2015 |
| Raw-Moon 56 Limited | Real estate | 2022 |
| Rawat Investments Limited | Real estate | 2021 |
| Rayne Scope Ltd | Information & communication | 2023 |
| Rayside Consulting Limited | Information & communication | 2026 |
| RB Design & Display Limited | Professional & scientific | 2005 |
| RC Effects Ltd | Professional & scientific | 2017 |
| RCB Solutions Limited | Construction | 2011 |
| RCD2 Ltd | Professional & scientific | 2025 |
| Reachcode Ltd | Extraterritorial | 2021 |
| Reading Property Investments Ltd | Real estate | 2017 |
| Real Property Tours Limited | Administrative & support | 2003 |
| Recoverwell Ltd | Health & social care | 2025 |
| Recruitpro Limited | Administrative & support | 2011 |
| Red Frog Plumbing and Heating Limited | Construction | 2023 |
| Red Lemon Events Ltd | Professional & scientific | 2022 |
| Red Ring Construction Ltd | Construction | 2020 |
| Red Sea Films Limited | Information & communication | 2012 |
| Reddy IT Services Limited | Information & communication | 2022 |
| Redhouse Ventures Holdings Ltd | Financial services | 2025 |
| Redhouse Ventures Limited | Construction | 2019 |
| Redlotus Services Limited | Professional & scientific | 2012 |
| Redsky Heights Ltd | Real estate | 2023 |
| Redsky Homes Ltd | Construction | 2015 |
| Redsky Rise Ltd | Construction | 2016 |
| Redsky Wholesalers Limited | Construction | 2004 |
| Redsky Willow Tree Ltd | Construction | 2023 |
| Redwood Founders Ltd | Education | 2024 |
| Redwood Law Limited | Professional & scientific | 2025 |
| Reesha Investments Limited | Real estate | 2010 |
| Reesha Limited | Professional & scientific | 2010 |
| Reference Point Limited | Information & communication | 1987 |
| Refherree Ltd | Hospitality | 2024 |
| Reflective Intelligence Limited | Information & communication | 2025 |
| Regal Property Limited | Real estate | 2021 |
| Regen Forestry Limited | Agriculture & fishing | 2019 |
| Regents Gate Reading Ltd | Real estate | 2025 |
| Rehabilitation Education and Community Homes Limited | Health & social care | 1995 |
| Reliable Retreats Limited | Real estate | 2019 |
| Renaissance Data Solutions Limited | Information & communication | 2018 |
| Rent 2 Buy Your Car London Ltd | Wholesale & retail | 2017 |
| Repair My Appliance Limited | Other services | 2014 |
| Research Culture Limited | Professional & scientific | 2021 |
| Reservoir Road Limited | Construction | 2004 |
| Resolve Esports Ltd | Arts & recreation | 2019 |
| Retailistic Limited | Professional & scientific | 2018 |
| Retro Alerts Ltd | Wholesale & retail | 2024 |
| Retrotastic Ltd | Wholesale & retail | 2024 |
| RFJ Music Ltd | Arts & recreation | 2022 |
| RFS Installations Ltd | Construction | 2017 |
| RG Bespoke Creations Ltd | Information & communication | 2021 |
| RGL Clinic Limited | Health & social care | 2018 |
| Ricci Obertelli Consultancy Limited | Professional & scientific | 2008 |
| Richa Enterprises Limited | Health & social care | 2016 |
| Richard Adams Pharma Limited | Other services | 2013 |
| Richard Anthony Classics Ltd | Wholesale & retail | 2017 |
| Richards Lettings Limited | Transport & logistics | 2021 |
| Ride a Cowboy Ltd | Administrative & support | 2024 |
| Ridgeline Partners Limited | Professional & scientific | 2026 |
| Rigby (London) Limited | Construction | 2004 |
| Rigby Investments Limited | Real estate | 2008 |
| Rilake Investments Ltd | Real estate | 2019 |
| Rishilok Limited | Real estate | 2004 |