| RAT Race Consulting Ltd | Professional & scientific | 2014 |
| Rauceby Estates Limited | Real estate | 2022 |
| Ravair Limited | Manufacturing | 2015 |
| Ravenswood Property Consulting Ltd | Professional & scientific | 2021 |
| RAW Copenhagen Ltd | Manufacturing | 2015 |
| RAW Honey Ltd | Hospitality | 2026 |
| RAW IT Ltd | Professional & scientific | 2023 |
| RAX2 Assets Limited | Wholesale & retail | 2019 |
| RAY Mullett Consultants Ltd | Water & waste | 2014 |
| RAY Mullett Solutions Limited | Professional & scientific | 2015 |
| Raynet Limited | Professional & scientific | 1980 |
| Rayo Cloud Ltd | Information & communication | 2023 |
| Raystrong Limited | Extraterritorial | 1989 |
| Razor Blades Ltd | Wholesale & retail | 2018 |
| Razor Thorn Security Ltd | Information & communication | 2007 |
| Razzle&Dazzle Ltd | Wholesale & retail | 2019 |
| RBD Sales Automation Ltd | Information & communication | 1995 |
| RBS Electrical Contractors Limited | Construction | 2003 |
| Rcas Properties Limited | Agriculture & fishing | 2012 |
| RD9 Automotive Ltd | Wholesale & retail | 2024 |
| Rdfr Ltd | Real estate | 2016 |
| RDW Design Ltd | Professional & scientific | 2023 |
| Reaching My Best Ltd | Extraterritorial | 2022 |
| React Swiftly Limited | Information & communication | 2026 |
| Readingworks Limited | Education | 2011 |
| Readybridge Ltd | Education | 2025 |
| Real Dine Ltd | Hospitality | 2025 |
| Real Time Accounting Ltd | Professional & scientific | 2002 |
| Realist Internet Consultants Limited | Information & communication | 2002 |
| Really Awesome Developments Limited | Real estate | 2021 |
| Realpoint Property Limited | Real estate | 2003 |
| Rearden Ltd | Information & communication | 2025 |
| Rebalance Pilates Ltd | Arts & recreation | 2024 |
| Rebecca Adams Post Limited | Information & communication | 2019 |
| Rebecca Dancer Music LLP | | 2012 |
| Rebecca Industries Ltd | Information & communication | 2023 |
| Rebecca Perkins Digital Ltd | Professional & scientific | 2024 |
| Rebeccanomics Limited | Professional & scientific | 2016 |
| Rebel Distillers Ltd | Manufacturing | 2015 |
| Recruitment Answers LLP | | 2012 |
| Red 7 Consultants Limited | Information & communication | 2007 |
| Red and Grey Creative Limited | Professional & scientific | 2015 |
| Red Dog Digital Limited | Information & communication | 2021 |
| Red Dragon Associates Limited | Professional & scientific | 2002 |
| Red Forest Limited | Professional & scientific | 2026 |
| Red Hire South Ltd | Administrative & support | 2022 |
| Red Kestrel Consulting Limited | Information & communication | 2007 |
| Red Nectar Limited | Professional & scientific | 2006 |
| Red Square Developments (Havant) LLP | | 2006 |
| Redboat Design Ltd | Information & communication | 2013 |
| Redbow Consulting Group Limited | Professional & scientific | 2014 |
| Redbox Construction and Project Management Ltd | Administrative & support | 2012 |
| Redfoot Limited | Information & communication | 2019 |
| Redhill Industrial Properties Limited | Real estate | 2016 |
| Redkitecrm Limited | Information & communication | 2015 |
| Redleaf VI (Stockton) Limited Partnership | | 2005 |
| Redspa Limited | Information & communication | 2010 |
| Reed Software Ltd | Information & communication | 2022 |
| Reel Impact Films Ltd | Information & communication | 2023 |
| Reel Productions Ltd | Arts & recreation | 2018 |
| Reflections Print Limited | Manufacturing | 1988 |
| Reflex Studio Limited | Manufacturing | 1978 |
| Regal Gate (Management) Limited | Real estate | 2017 |
| Regalpoint Clarence House Management Co. Limited | Real estate | 2007 |
| Regen Roasting Company Ltd | Hospitality | 2025 |
| Regency House (Tunbridge Wells) Limited | Households | 2009 |
| Regent Place Management Limited | Households | 2002 |
| Regent's Consulting Limited | Professional & scientific | 2025 |
| Regina Court Residents Association Limited | Households | 1990 |
| Rehab Pilates Ltd | Other services | 2019 |
| Reid Consultancy Services Ltd | Information & communication | 2024 |
| Reign When It's Raining Ltd | Professional & scientific | 2023 |
| Reinar Properties Limited | Real estate | 2020 |
| Rekt Industries Ltd | Wholesale & retail | 2021 |
| Relevant Bookkeeping & Accounts Ltd | Professional & scientific | 2019 |
| Relevare Midco Limited | Extraterritorial | 2026 |
| Relevare Topco Limited | Extraterritorial | 2026 |
| Reliance Recovery Limited | Other services | 1977 |
| Renand Assets LLP | | 2018 |
| Renand Holdings Limited | Other services | 2018 |
| Renand Properties Limited | Construction | 1997 |
| Renand Residential Limited Liability Partnership | | 2006 |
| Renicks Ltd | Information & communication | 2018 |
| Repack Clothing Limited | Wholesale & retail | 2010 |
| Reprimard Limited | Hospitality | 1977 |
| Reprobus Ltd | Construction | 2014 |
| Reputation Value Limited | Professional & scientific | 2013 |
| Resident Property Software Limited | Information & communication | 2014 |
| Residential & Domestic Fire Sprinkler Company Limited | Construction | 2004 |
| Residents 138 Upper Grosvenor Road Ltd | Households | 2018 |
| Resilience by Design Ltd | Professional & scientific | 2017 |
| Resilientos Ltd | Information & communication | 2026 |
| Resolis Consultancy Ltd | Professional & scientific | 2024 |
| Resolveyourclaim Limited | Financial services | 2020 |
| Respace Ltd | Construction | 2009 |
| Respirex International Limited | Manufacturing | 1957 |
| Retail Electrical Solutions Limited | Construction | 2013 |
| Retoucherie Ltd | Information & communication | 2020 |
| Retrocards Ltd. | Wholesale & retail | 2011 |
| Reuben J Cogburn Ltd | Professional & scientific | 2023 |