| Reign Studio Ltd | Wholesale & retail | 2019 |
| Reignite Construction Limited | Real estate | 2023 |
| Reignite Investments Limited | Real estate | 2023 |
| Reignite Properties Limited | Financial services | 2023 |
| Reina Group Ventures Ltd | Wholesale & retail | 2024 |
| Reine Deluxe Limited | Other services | 2022 |
| Reins Limited | Financial services | 2012 |
| Reinwear Limited | Wholesale & retail | 2023 |
| Relax Limited | Financial services | 2021 |
| Relax U.K. Ltd. | Wholesale & retail | 1997 |
| Relco Property Services Limited | Administrative & support | 2018 |
| Reldas Group Limited | Professional & scientific | 2017 |
| Relec Limited | Manufacturing | 2018 |
| Reliable Freight Ltd | Transport & logistics | 2022 |
| Reliable Software Ltd | Information & communication | 2019 |
| Reliance Construction Group Limited | Construction | 2025 |
| Reliante Ltd | Administrative & support | 2025 |
| Relive Limited | Real estate | 2015 |
| Rellam Homes Limited | Real estate | 2017 |
| Relocon T/A the Weave Limited | Professional & scientific | 2019 |
| REM Lettings Limited | Real estate | 2016 |
| Remappack Limited | Information & communication | 2022 |
| Remaster Your Mind Limited | Other services | 2020 |
| Remnants Care Ltd | Health & social care | 2025 |
| Remnants of Love Ltd | Manufacturing | 2024 |
| Remnnt Ltd | Professional & scientific | 2019 |
| Remote Medic UK Ltd | Health & social care | 2011 |
| Remval Management Limited | Extraterritorial | 2011 |
| Renew Africa Limited | Financial services | 2025 |
| Renkan Limited | Information & communication | 2013 |
| Renova Property Services Ltd | Construction | 2023 |
| Renovate 2 Inspire Ltd | Other services | 2020 |
| Renovatio Fire Safety Limited | Wholesale & retail | 2011 |
| Renovest Properties Ltd | Real estate | 2025 |
| Renovo Engineering Ltd | Professional & scientific | 2006 |
| Rent @ Residential Lettings Limited | Real estate | 2020 |
| Rent NOW Limited | Real estate | 2021 |
| Rentals & Recoveries (South East) Ltd | Administrative & support | 2025 |
| Renting Solutions Limited | Real estate | 2016 |
| Rentopia (East Anglia) Ltd | Real estate | 2023 |
| Rents R.V Limited | Real estate | 2024 |
| Rentville Properties Ltd | Real estate | 2019 |
| Repair Solutions Group Ltd | Construction | 2011 |
| Repark Engineering Ltd | Professional & scientific | 2021 |
| Repgrow Ltd | Administrative & support | 2025 |
| Repiped Group Limited | Construction | 2026 |
| Repto Business LAB Ltd | Information & communication | 2024 |
| Repurpose Ltd | Wholesale & retail | 2016 |
| Reraig Caravan and Camping Limited | Hospitality | 2021 |
| Research Complete Ltd | Professional & scientific | 2023 |
| Reshape Fit Limited | Arts & recreation | 2026 |
| Resicraft Ltd | Construction | 2022 |
| Residents Management (NO. 69) Limited | Hospitality | 1986 |
| Resilience Academy Limited | Education | 2017 |
| Resilire Advisory Services Limited | Professional & scientific | 2023 |
| Resin Flooring Solutions (UK) Limited | Construction | 2014 |
| Resistance Partners Limited | Professional & scientific | 2012 |
| Resmiranda Ltd | Professional & scientific | 2015 |
| Resolve Building Services Limited | Construction | 2006 |
| Resolve Business Management Ltd | Other services | 2018 |
| Resolve Legal Solutions Ltd | Professional & scientific | 2021 |
| Resolve Scaffolding Ltd | Construction | 2022 |
| Response SW Ltd | Other services | 2014 |
| Responsive Property Maintenance Limited | Extraterritorial | 2019 |
| Rest Travel Ltd | Administrative & support | 2026 |
| Restart Racing Ltd | Administrative & support | 2023 |
| Restaurant Galaxy Mambo Limited | Hospitality | 2017 |
| Restbss Ltd | Administrative & support | 2026 |
| Restful Soap Ltd | Professional & scientific | 2023 |
| Resuk Ltd | Construction | 2025 |
| Result Clothing Limited | Wholesale & retail | 1995 |
| Retail Foundation | Real estate | 2018 |
| Rethinking Financial Services Ltd | Financial services | 2022 |
| Retina Properties Limited | Real estate | 2024 |
| Retina Space Limited | Professional & scientific | 2023 |
| Retirement Planning Partnership Ltd | Administrative & support | 1986 |
| Retiva Investments Ltd | Real estate | 2017 |
| Retrac Solutions Ltd | Construction | 2025 |
| Retract Screens Limited | Manufacturing | 2020 |
| Retreat Living Ltd | Real estate | 2023 |
| Retro DUB Suffolk Limited | Other services | 2018 |
| Retro Route UFH Ltd | Construction | 2019 |
| Retroprops Limited | Administrative & support | 2004 |
| Revalprime Ltd | Professional & scientific | 2025 |
| Revamp Paving & Fencing Limited | Administrative & support | 2025 |
| Revant Ltd | Real estate | 2026 |
| Reveal Projects Limited | Real estate | 2018 |
| Reverie Apps Ltd | Information & communication | 2025 |
| Reverie Colchester UK Holdings Limited | Financial services | 2022 |
| Reverie Composites Limited | Real estate | 2014 |
| Reverie EOT Limited | Financial services | 2022 |
| Reverie Limited | Manufacturing | 2000 |
| Revive at Rhigos Retreat Ltd | Hospitality | 2023 |
| Revive Counselling & Psychotherapy C.I.C. | Health & social care | 2025 |
| Revive Health Ltd | Health & social care | 2021 |
| Revive Restorations Ltd | Administrative & support | 2022 |
| Revive Sustainable Design Co Limited | Professional & scientific | 2021 |
| Revlac Auto Engineers Limited | Wholesale & retail | 2011 |
| Revlodge Limited | Real estate | 1977 |
| Revolution Learning and Development Ltd | Education | 2009 |