| RAJ G Food and Wine Ltd | Wholesale & retail | 2025 |
| RAJ Heating Ltd | Manufacturing | 2012 |
| Ralph Bettany Associates Ltd. | Real estate | 1999 |
| Ralrae Limited | Professional & scientific | 2018 |
| RAM 2032 Limited | Extraterritorial | 2021 |
| Ramie Limited | Professional & scientific | 2007 |
| Rampetuss Ltd | Information & communication | 2021 |
| Ramruay Chang Thai Ltd | Hospitality | 2025 |
| Ramsarms Limited | Real estate | 2024 |
| RAND2AI Limited | Financial services | 2025 |
| Randell & Janes Roofing Specialists Limited | Construction | 2006 |
| Rani's Brow & Eyelash Lounge Ltd | Other services | 2019 |
| Rani's File & Style Boutique Limited | Other services | 2025 |
| RAP Communications Limited | Information & communication | 2016 |
| RAPID007 Limited | Wholesale & retail | 2022 |
| Rapidgrid Group of Companies Limited | Financial services | 2021 |
| Rapidleap Ltd | Real estate | 2021 |
| Rascala Limited | Administrative & support | 2017 |
| Rascala Loans Limited | Administrative & support | 2017 |
| Ratecost Limited | Real estate | 1995 |
| Ratelion Limited | Real estate | 2019 |
| Raum Ltd | Professional & scientific | 2014 |
| Raven Delta Limited | Financial services | 2018 |
| Raven Delta R&D Ltd | Professional & scientific | 2026 |
| Ravenhill Kebab Ltd | Hospitality | 2025 |
| Ravfox Limited | Real estate | 1982 |
| Ravs Vintage Ltd | Wholesale & retail | 2024 |
| Ravspec Ltd | Wholesale & retail | 2023 |
| RAW Construction Environmental International Limited | Construction | 2022 |
| RAW Haus Interiors Limited | Wholesale & retail | 2020 |
| Rawand Mostafa Ltd | Other services | 2025 |
| Rawelec Ltd. | Construction | 2021 |
| Rawr&More Ltd | Wholesale & retail | 2023 |
| Raybould Enterprises Limited | Wholesale & retail | 2010 |
| Raymond Wood Enterprises Limited | Extraterritorial | 1998 |
| RAZ UK Property Limited | Real estate | 2025 |
| Razitech Ltd | Professional & scientific | 2026 |
| RB Build and Renovation Ltd | Construction | 2026 |
| RB Construction Services Ltd | Construction | 2016 |
| RB Electrical Swansea Ltd | Construction | 2015 |
| RB Food House Ltd | Hospitality | 2025 |
| RB Kebab House Limited | Hospitality | 2025 |
| RB Wealth Ltd | Financial services | 2026 |
| RBD Decorating Limited | Construction | 2023 |
| RBL Partnership Limited | Construction | 2014 |
| RBM Accountancy Limited | Professional & scientific | 2015 |
| RBS Scaffold Ltd | Construction | 2023 |
| RBS Traders UK Ltd | Wholesale & retail | 2020 |
| Rbuddie Ltd | Other services | 2019 |
| RBW Executive and Professional Coaching Ltd | Professional & scientific | 2023 |
| Rccg Victory Springs Ltd | Other services | 2025 |
| RCF Properties Ltd | Real estate | 2023 |
| Rchala Home Limited | Real estate | 2021 |
| Rcv-Tech Ltd | Professional & scientific | 2013 |
| RD Home Renovations Ltd | Construction | 2021 |
| RD Infotech Ltd | Information & communication | 2024 |
| RD Jones Building Ltd | Construction | 2022 |
| RD Solar and Building Ltd | Construction | 2024 |
| RD Steel Industries Limited | Wholesale & retail | 2024 |
| RDB Logistics Limited | Transport & logistics | 2019 |
| Rddiamond Limited | Transport & logistics | 2023 |
| RDE Developments Limited | Construction | 2000 |
| RDG Consulting Ltd | Professional & scientific | 2019 |
| RDH Companies Ltd | Administrative & support | 2018 |
| RDH Electrical Limited | Manufacturing | 2017 |
| RDM Brands Limited | Manufacturing | 2020 |
| RDM Engineering Solutions Limited | Professional & scientific | 2023 |
| RDM Enterprises Ltd | Financial services | 2023 |
| RDM Retail Ltd | Wholesale & retail | 2019 |
| RDM Services (Property & Landscaping) Limited | Construction | 2013 |
| RDM Swansea Ltd | Wholesale & retail | 2022 |
| RDN Group Limited | Financial services | 2020 |
| RE Controls Ltd | Professional & scientific | 2021 |
| Re-Cycle South Wales Community Interest Company | Arts & recreation | 2011 |
| Re-Source Enterprises Ltd | Financial services | 2021 |
| Re-Treat CBD Ltd | Wholesale & retail | 2018 |
| Re-Vitalize Global Ltd | Arts & recreation | 2023 |
| Re-Worked Limited | Manufacturing | 2025 |
| Re.Tek.B-Design Ltd | Construction | 2019 |
| Reable Ltd | Health & social care | 2006 |
| Reaching for Green UK Ltd | Manufacturing | 2026 |
| Reaching Making Point Ltd | Other services | 2026 |
| Reachout Trust | Information & communication | 2001 |
| React Digital Limited | Information & communication | 2016 |
| React Training Ltd | Education | 2024 |
| React Utilities Group Ltd | Health & social care | 2023 |
| Reactodamp Ltd | Construction | 2018 |
| Reading Support for Parents Ltd | Education | 2022 |
| Real ALM Limited | Information & communication | 2026 |
| Real JET Crew Ltd | Administrative & support | 2025 |
| Real Time Accountancy Services Ltd | Professional & scientific | 2013 |
| Reality 42 Limited | Information & communication | 2002 |
| Really Great Cruises Limited | Administrative & support | 2009 |
| Really Reliable Ltd | Construction | 2023 |
| Realmont Onestop Ltd | Wholesale & retail | 2025 |
| Reasonclever Company Limited | Hospitality | 1993 |
| Reba Khanom Limited | Hospitality | 2018 |
| Rebekah Homes Ltd | Real estate | 2023 |
| Rebel Wholesale Ltd | Wholesale & retail | 2022 |
| Recherche Living Ltd | Real estate | 2020 |