| Rentcab Ltd | Transport & logistics | 2026 |
| Renteze Limited | Real estate | 2025 |
| Rently Solutions Limited | Information & communication | 2024 |
| Rentology Group Ltd | Real estate | 2024 |
| Rentreward Technologies Ltd | Information & communication | 2025 |
| Rentway Ltd | Wholesale & retail | 2012 |
| René House CIC | Hospitality | 2018 |
| Reobuildingsolutions Ltd | Arts & recreation | 2024 |
| Reorg Developments Limited | Real estate | 2019 |
| Reorg Installations Limited | Construction | 2019 |
| Reorg Investments Limited | Real estate | 2020 |
| Repair and Refinish Coatings Limited | Other services | 2020 |
| Repair My Car Ltd | Wholesale & retail | 2013 |
| Repair My Engine Ltd | Wholesale & retail | 2020 |
| Repeat Digital Ltd | Professional & scientific | 2017 |
| Replan Architects Ltd | Professional & scientific | 2019 |
| Replenish Collective Ltd | Hospitality | 2025 |
| Reporapro Ltd | Information & communication | 2025 |
| Reportassist Limited | Information & communication | 2012 |
| Repton Estates Ltd | Real estate | 2021 |
| Repton Projects Limited | Information & communication | 2009 |
| Reputation Management Group Limited | Professional & scientific | 2024 |
| Rera Private Limited | Real estate | 2025 |
| Reraw Ltd | Information & communication | 2017 |
| Rerender Ltd | Professional & scientific | 2023 |
| Rerrie Rail EM Limited | Construction | 2016 |
| Rerum Consultancy UK Ltd | Wholesale & retail | 2021 |
| Rerum Ingredients Limited | Professional & scientific | 2009 |
| Res-Q ME Ltd | Transport & logistics | 2024 |
| Rescue ME Ltd | Information & communication | 2026 |
| Research Consulting Limited | Professional & scientific | 2013 |
| Research Force Ltd | Professional & scientific | 2023 |
| Research Nexus Limited | Professional & scientific | 2025 |
| Research Wise AI Limited | Information & communication | 2023 |
| Reserve Power Trading Limited | Energy | 2015 |
| Reset, Reshape & Thrive Ltd | Arts & recreation | 2023 |
| Reshungha Foods Ltd | Hospitality | 2022 |
| Residential Mortgage Services Limited | Financial services | 2017 |
| Residential Structural Services Limited | Professional & scientific | 2022 |
| Residentures Group Ltd | Real estate | 2024 |
| Resie Limited | Financial services | 2025 |
| Resilience HCP Ltd | Administrative & support | 2021 |
| Resilience Power Limited | Energy | 2024 |
| Resilient Wealth Ltd | Real estate | 2024 |
| Resin Anchor Limited | Manufacturing | 2020 |
| Resin Bonded Surfacing Limited | Construction | 2008 |
| Resin Tanking & Tiling Ltd | Construction | 2017 |
| Resinique Ltd | Wholesale & retail | 2025 |
| Resolute Care Holdings Ltd | Public administration | 2023 |
| Resolute Care Ltd | Health & social care | 2014 |
| Resolve Educate Advocate Lead CIC | Education | 2025 |
| Resolve Electrical Services Ltd | Construction | 2013 |
| Resolve Heating and Plumbing Limited | Construction | 2015 |
| Resonance AI Ltd | Information & communication | 2026 |
| Resource 5 Ltd | Professional & scientific | 2022 |
| Resource Recovery Midlands Ltd | Water & waste | 2023 |
| Resourcefully Ltd | Education | 2021 |
| Respcare Ltd | Health & social care | 2024 |
| Respect Couriers Ltd | Transport & logistics | 2023 |
| Respect for Animals Educational Trust Limited | Education | 1996 |
| Response Auto Repair Centre Ltd | Wholesale & retail | 2015 |
| Response Healthcare Group Ltd | Other services | 2016 |
| Response Occupational Health Ltd | Other services | 2021 |
| Response Physiotherapy DL Limited | Other services | 2016 |
| Response Physiotherapy Limited | Arts & recreation | 2005 |
| Response Physiotherapy Partners LLP | | 2018 |
| Response Primary Care Ltd | Extraterritorial | 2023 |
| Response-Able Solutions Ltd | Transport & logistics | 2006 |
| Responsive Analytix Limited | Professional & scientific | 2022 |
| Responsive Consultancy Ltd | Health & social care | 2020 |
| Restaurant SAT Bains Ltd | Hospitality | 2004 |
| Restoration Architecture Ltd | Information & communication | 2025 |
| Restoration HUT Ltd | Other services | 2016 |
| Restore Empower Perform Physiotherapy Limited | Health & social care | 2025 |
| Restore Your Looks Ltd | Other services | 2015 |
| Restorea Limited | Wholesale & retail | 2019 |
| Result Construction&Maintenance Limited | Construction | 2026 |
| Resunga Ltd | Real estate | 2026 |
| Retail Express HK Ltd | Wholesale & retail | 2025 |
| Retail Parking Solutions (UK) Limited | Transport & logistics | 2012 |
| Retail-Ready Consulting Limited | Professional & scientific | 2018 |
| Retex Recycling Limited | Water & waste | 2012 |
| Retford Limited | Wholesale & retail | 2002 |
| Retreat Hair & Beauty Salon Ltd | Other services | 2015 |
| Retro Design and Sign Ltd | Manufacturing | 2021 |
| Retro Engineers Ltd | Professional & scientific | 2016 |
| Retro Technical Ltd | Professional & scientific | 2024 |
| Retslaw Ltd | Real estate | 2022 |
| Retter Medical Services Ltd | Health & social care | 2019 |
| Reubeden Ventures Ltd | Extraterritorial | 2011 |
| Reuben Engineering Ltd | Professional & scientific | 2019 |
| Reubens Court Management Limited | Real estate | 2008 |
| Reunion Management Company Ltd | Hospitality | 2024 |
| Reunion PUB Company Ltd | Hospitality | 2022 |
| Reva Environmental Limited | Water & waste | 2018 |
| Reva Management & Consultancy Ltd | Administrative & support | 2010 |
| Revamp My Kitchen Limited | Administrative & support | 2015 |
| Revastra Global Limited | Information & communication | 2025 |
| Reveal Ceramics Limited | Construction | 2014 |
| Revelectrics Ltd | Construction | 2022 |