| Realistic Estate Planning Ltd | Financial services | 2023 |
| Realistic Financial Planning Ltd | Financial services | 2013 |
| Realtime Promo Ltd | Arts & recreation | 2016 |
| Reason Property Holding Ltd | Real estate | 2026 |
| Rebel Counselling & Coaching LLP | | 2021 |
| Rebel Inns Limited | Real estate | 2011 |
| Rebel Restaurants Limited | Hospitality | 2012 |
| Rebel Riders Motorcycles Limited | Wholesale & retail | 2021 |
| Recel Limited | Wholesale & retail | 2023 |
| Recruis Ltd | Information & communication | 2025 |
| Recruit Hub Limited | Administrative & support | 2017 |
| Recyc-Line Ltd | Water & waste | 2019 |
| Red Lion Court Developments Limited | Administrative & support | 2008 |
| Red Portfolio Limited | Real estate | 2018 |
| RED28 Trans Ltd | Transport & logistics | 2026 |
| Redbridge Civic Services Ltd | Water & waste | 2019 |
| Redbridge Regeneration Limited | Administrative & support | 2016 |
| Reddo Care and Support C.I.C. | Health & social care | 2010 |
| Redec Industrial Limited | Professional & scientific | 2005 |
| Redec Industrial Management Limited | Professional & scientific | 2002 |
| Redington Developments (Apsley) Limited | Construction | 2020 |
| Redkara Limited | Financial services | 2021 |
| Redland Construction Limited | Construction | 2019 |
| Redline Building & Maintenance Ltd | Construction | 2024 |
| Redline Fire Protection Ltd | Construction | 2025 |
| Reece Management Limited | Financial services | 1990 |
| Reef Ventures Limited | Real estate | 2011 |
| Reefmark Limited | Administrative & support | 1999 |
| REF Builders Ltd | Construction | 2025 |
| Refan Beauty Ltd | Wholesale & retail | 2022 |
| Refargo Limited | Wholesale & retail | 2025 |
| Reflex Bridging Limited | Administrative & support | 2011 |
| Reflex Property Finance Ltd | Administrative & support | 2022 |
| Reformed Pilates Studio Limited | Arts & recreation | 2024 |
| Refraym Ltd | Professional & scientific | 2026 |
| Regal Court NO. 4 Limited | Administrative & support | 2001 |
| Regalrent Limited | Real estate | 1996 |
| Regalzest Limited | Administrative & support | 2006 |
| Regent Gate Estate (Management) Limited | Real estate | 1989 |
| Regenta Development Limited | Construction | 2014 |
| Regenta International Limited | Real estate | 2025 |
| Regenta Ltd | Real estate | 1989 |
| Regulatory Strategies Limited | Administrative & support | 2020 |
| Reign Renewables Ltd | Other services | 2023 |
| Reis DO Cabaz Ltd | Wholesale & retail | 2025 |
| Rejuvaderm Aesthetics Ltd | Health & social care | 2025 |
| Reliable Space Ltd | Transport & logistics | 2025 |
| Reliance Trade & Investments Ltd | Real estate | 2024 |
| Remedy Medical Solutions Limited | Professional & scientific | 2006 |
| Remedy Recruitment Group Limited | Administrative & support | 2003 |
| Remedy Tutors Limited | Administrative & support | 2025 |
| Remi Contractors Ltd | Construction | 2014 |
| Remway Ltd | Real estate | 2025 |
| Renaissance Flooring Limited | Construction | 2019 |
| Renatus Construction Ltd | Construction | 2023 |
| Renderseal Limited | Administrative & support | 1999 |
| Renegade Life Ltd | Public administration | 2025 |
| Reneviato Limited | Professional & scientific | 2013 |
| Renewable Energy Waste Solutions UK PLC | Manufacturing | 2017 |
| Renfoproperties Ltd | Real estate | 2019 |
| Renford Builders Limited | Construction | 1983 |
| Renova Recycling Ltd | Water & waste | 2024 |
| REP Industrial Holdings Limited | Financial services | 2014 |
| REP Installations Limited | Construction | 2001 |
| REP Southern Limited | Construction | 2019 |
| Replica Solutions Limited | Administrative & support | 2009 |
| Reputeone Limited | Information & communication | 2025 |
| Research International Limited | Information & communication | 2018 |
| Reserve Company 2026 Limited | Information & communication | 2026 |
| Resett Ltd | Public administration | 2023 |
| Resi Developments Limited | Real estate | 1995 |
| Residential Fire Safety Ltd | Education | 2025 |
| Resolution Periodontics Limited | Health & social care | 2023 |
| Resto Restoration Limited | Construction | 2026 |
| Restore and Flow Ltd | Health & social care | 2025 |
| Restored Alchemy Ltd | Manufacturing | 2020 |
| Retail Pro-Fit Ltd | Professional & scientific | 2008 |
| Retainabl. Ltd | Manufacturing | 2026 |
| Retallack Holidays Limited | Administrative & support | 2012 |
| Reumart Limited | Construction | 2017 |
| Revolution Leisure Limited | Arts & recreation | 2003 |
| Revospace Consulting Ltd | Professional & scientific | 2025 |
| Rewt Asset Management Limited | Professional & scientific | 2015 |
| REX Publications Limited | Information & communication | 1990 |
| Rey's Properties Ltd | Real estate | 2025 |
| Reynolds Fire and Security Ltd | Administrative & support | 2026 |
| RFM Management Ltd | Professional & scientific | 2007 |
| Rhobok Contractors Limited | Construction | 2019 |
| Rhoka Ltd | Construction | 2025 |
| Richard Bradley Limited | Real estate | 2023 |
| Riches Bespoke Furniture Specialist Ltd | Manufacturing | 2018 |
| Richie's Audit Services Limited | Professional & scientific | 2008 |
| Richter & Law Consultation Ltd | Health & social care | 2026 |
| Rickshaw Properties Ltd | Real estate | 2021 |
| Ricky Paul Flowers Limited | Other services | 2012 |
| Ridgeton Limited | Administrative & support | 2005 |
| Ridley Hall Consultancy Limited | Professional & scientific | 2001 |
| Right Removals London Ltd | Transport & logistics | 2023 |
| Rinat Ltd | Construction | 2012 |
| Rinatel Limited | Real estate | 2017 |