| RE7CC Limited | Extraterritorial | 2002 |
| Reaal Motors Ltd | Wholesale & retail | 2023 |
| Reactive Marketing Services Ltd | Professional & scientific | 2023 |
| Readings Property Services LLP | | 2017 |
| Ready for AI Ltd | Education | 2026 |
| Ready Steady Sports Ltd | Education | 2026 |
| Real Business Solutions and Services Consulting Ltd | Professional & scientific | 2011 |
| Real Enotion Ltd | Wholesale & retail | 2023 |
| Real Estate Investment Corporation Limited | Real estate | 2006 |
| Real Estates Investments Limited | Financial services | 2025 |
| Real Grill Food Limited | Hospitality | 2026 |
| Real Highways Ltd | Professional & scientific | 2022 |
| Real Reserve Ltd | Real estate | 2023 |
| Real Rhythm School of Dancing Limited | Arts & recreation | 2015 |
| Real Shine Stone Ltd | Construction | 2012 |
| Realgem Investments Limited | Real estate | 2003 |
| Reali Industrial Solutions Ltd | Wholesale & retail | 2022 |
| Reality Shift Ltd. | Information & communication | 2014 |
| Really Good Productions Ltd | Information & communication | 2024 |
| Realm Trade Limited | Wholesale & retail | 2025 |
| Realty Quest Ltd | Real estate | 2024 |
| Rebeca Engineering Limited | Construction | 2017 |
| Rebeca Services Ltd | Construction | 2021 |
| Rebel ERP Ltd | Information & communication | 2023 |
| Rebi Traders Limited | Wholesale & retail | 2019 |
| Rebugo Ltd | Transport & logistics | 2026 |
| Receiptium (UK) Limited | Information & communication | 2019 |
| Recludo Consulting Ltd | Professional & scientific | 2015 |
| Recordglen Limited | Professional & scientific | 1988 |
| Recorr Ltd | Professional & scientific | 2020 |
| Recovery 1 Ltd | Manufacturing | 2025 |
| Recovery Singh Ltd | Transport & logistics | 2026 |
| Recruitment Choice Ltd | Administrative & support | 2019 |
| Recrut Skill Ltd | Administrative & support | 2022 |
| Recycle Logix Ltd | Water & waste | 2025 |
| Red Bike Limited | Professional & scientific | 2015 |
| Red Cube Recruitment Ltd | Administrative & support | 2013 |
| Red Dipes Limited | Wholesale & retail | 2010 |
| Red Electric Designs Limited | Construction | 2001 |
| Red Group 2016 Ltd | Construction | 2016 |
| Red Group Plant Hire Ltd | Administrative & support | 2016 |
| Red Hot Mango Ltd | Wholesale & retail | 2019 |
| Red Line Maintenance Ltd | Construction | 2025 |
| Red Lodge Holdings Ltd | Real estate | 2021 |
| Red Lorry Yellow Lorry Ltd | Professional & scientific | 2024 |
| Red Peak Compliance Limited | Professional & scientific | 2024 |
| Red POT Limited | Professional & scientific | 2024 |
| Red Power 1 Ltd | Wholesale & retail | 2023 |
| Red Radiance Ltd | Wholesale & retail | 2011 |
| Red Squirrel Moves Ltd | Administrative & support | 2006 |
| Red Stone 1 Ltd | Transport & logistics | 2026 |
| Red Trangle IT Solutions Limited | Information & communication | 2010 |
| Red Turtle Integrated Design Limited | Professional & scientific | 2024 |
| Red Velvet Decor UK Ltd | Hospitality | 2024 |
| Red Wind Energy Limited | Energy | 2012 |
| Redbrick (Essex) LLP | | 2023 |
| Redbrick Land & Property Limited | Real estate | 2023 |
| Redbridge Accountant Ltd | Professional & scientific | 2010 |
| Redbridge Amateur Boxing Club | Arts & recreation | 2013 |
| Redbridge Shop Front Limited | Construction | 2016 |
| Redcoat IT Services Limited | Information & communication | 2016 |
| Reddisher Limited | Real estate | 2020 |
| Redeemed Christian Church of GOD Gloryland Connections | Other services | 2019 |
| Redex Support Ltd | Administrative & support | 2025 |
| Redfern Catering Ltd | Hospitality | 2018 |
| Redfern Consulting Solutions Limited | Information & communication | 2013 |
| Redhawk Roofing Contractors Ltd | Construction | 2026 |
| Redin KRD Ltd | Wholesale & retail | 2026 |
| Redlands Farm Limited | Real estate | 2025 |
| Redlaw Contracts Ltd | Construction | 2014 |
| Redlaw Management Ltd | Real estate | 2006 |
| Redrawing the Line Ltd | Health & social care | 2018 |
| Reds Consultancy Ltd | Professional & scientific | 2015 |
| Redwin Sibley Ltd | Professional & scientific | 2005 |
| Reebz Limited | Wholesale & retail | 2021 |
| Rees Fire Ltd | Professional & scientific | 2022 |
| Reeva and RAE Ltd | Wholesale & retail | 2020 |
| Refelects Limited | Wholesale & retail | 2023 |
| Refine BMC Ltd | Construction | 2016 |
| Refine Contractors Limited | Other services | 2025 |
| Reflecto Global Ltd | Wholesale & retail | 2026 |
| Reformedia Ltd | Information & communication | 2025 |
| Refrigerated Shipbroking Limited | Transport & logistics | 2016 |
| Refrigeration Technology Limited | Professional & scientific | 2013 |
| Regal Bespoke Management Limited | Transport & logistics | 2024 |
| Regal Boxing CIC | Other services | 2023 |
| Regal Jewellers Limited | Wholesale & retail | 2025 |
| Regalton Limited | Wholesale & retail | 2016 |
| Regen Homes Group Ltd | Real estate | 2025 |
| Regency Fashions Limited | Manufacturing | 2013 |
| Regenfirst Limited | Real estate | 2021 |
| Regent Court (Gidea Park) Ltd | Households | 2003 |
| Reggie Events Ltd | Hospitality | 2020 |
| Reggie Films Ltd | Information & communication | 2024 |
| Regiment K9 Force Ltd | Administrative & support | 2022 |
| Rehall Holdings Limited | Financial services | 2018 |
| Rehan Automotive Ltd | Wholesale & retail | 2026 |
| Rehan Traders Ltd | Wholesale & retail | 2024 |
| Rehber Limited | Extraterritorial | 2018 |
| Rehmaat Ltd | Hospitality | 2026 |