| Ranking Recordings Ltd | Arts & recreation | 2012 |
| Rapid Route Recruitment Ltd | Administrative & support | 2026 |
| Rapidfix Plumbing Ltd | Construction | 2024 |
| Rare Ice Limited | Wholesale & retail | 2014 |
| Ravensmere Limited | Real estate | 2015 |
| RAW4DOGS Ltd | Wholesale & retail | 2020 |
| Rawganic Passion Ltd | Construction | 2016 |
| RAY Linge Market Stalls Limited | Administrative & support | 2016 |
| RAY Moore Consultancy & Training Ltd | Administrative & support | 2015 |
| Raycubed Properties Limited | Real estate | 2021 |
| RB AME Ltd | Professional & scientific | 2019 |
| RB Corporate Services Limited | Professional & scientific | 2010 |
| RC Carhire Ltd | Administrative & support | 2022 |
| RC Projects Holdings Ltd | Administrative & support | 2023 |
| RD Collier Limited | Other services | 2015 |
| RD Surveying Ltd | Construction | 2014 |
| RDB2 Holdings Limited | Financial services | 2023 |
| RDB3 Holdings Limited | Financial services | 2023 |
| RDB4 Holdings Limited | Financial services | 2024 |
| RDM Transport Limited | Administrative & support | 2009 |
| Rdms Investment Ltd | Real estate | 2018 |
| Rdot Productions Limited | Administrative & support | 2026 |
| Re:Studio Ltd | Professional & scientific | 2022 |
| Read Between the Wines Ltd | Wholesale & retail | 2026 |
| Ready SET Assist Ltd | Information & communication | 2025 |
| Real Fire Sprinkler System Ltd | Construction | 2024 |
| Real Renovations Limited | Construction | 2023 |
| Reales Care Limited | Health & social care | 2015 |
| Realisable Software Limited | Information & communication | 2008 |
| Realness Trading Ltd | Hospitality | 2015 |
| Rebuildr Ltd | Construction | 2020 |
| Recci Ltd | Information & communication | 2026 |
| Record Life Limited | Manufacturing | 2019 |
| Record TV Network Limited | Information & communication | 2004 |
| Recycling and Environmental Service Brokers Limited | Administrative & support | 2005 |
| Red Cedar Property Ltd | Real estate | 2020 |
| Red COW Cheshunt Limited | Hospitality | 2014 |
| Red DOT Cameras Limited | Administrative & support | 2007 |
| Red DOT Photo Books Limited | Administrative & support | 2017 |
| Red London Properties Limited | Administrative & support | 2015 |
| Red PDA Ltd | Financial services | 2020 |
| Redbridge Building Services Limited | Construction | 2021 |
| Redbridge Motor World Limited | Wholesale & retail | 2024 |
| Redcopters Ltd | Professional & scientific | 2012 |
| Reddish Express Pizza Ltd | Hospitality | 2019 |
| Redfin IT Ltd | Information & communication | 2022 |
| Redivivus Worldwide Limited | Energy | 2021 |
| Rednest Properties Limited | Real estate | 2016 |
| Redpill Training Ltd | Other services | 2024 |
| Redwan UK Limited | Hospitality | 2021 |
| REE Holdings Limited | Administrative & support | 2023 |
| Reed Nation Ltd | Administrative & support | 2019 |
| Reform by Energym Ltd | Administrative & support | 2026 |
| Refovea Ltd | Health & social care | 2024 |
| Regalpress Limited | Information & communication | 2000 |
| Regency Jewels Limited | Wholesale & retail | 2012 |
| Regeneration Sub-Ocean (GP) Limited | Administrative & support | 2018 |
| Regeneration Sub-Ocean Limited Partnership | | 2018 |
| Regent Court (Princes Road) Management Company Limited | Households | 1995 |
| Regent Electrical Services Ltd | Construction | 2020 |
| Regents Accountancy and Payroll Service Ltd | Professional & scientific | 2001 |
| Regents Park Youth League Ltd | Arts & recreation | 2020 |
| Regnas Holdings Limited | Real estate | 2025 |
| Regulation Assist Limited | Professional & scientific | 2025 |
| Rehkin Properties Limited | Real estate | 2025 |
| Rejuvenation by Rachel Ltd. | Other services | 2019 |
| REL Holdings Ltd | Real estate | 2019 |
| REL MEP Ltd | Construction | 2011 |
| Reliance Capital Partners Limited | Real estate | 2018 |
| Reliance Transport Limited | Transport & logistics | 1993 |
| Rembrandt Group Ltd | Health & social care | 2024 |
| Renaistre Consulting Ltd | Professional & scientific | 2023 |
| Renda Edumind Limited | Construction | 2019 |
| Renewability Group Limited | Construction | 2023 |
| Renova Lifesciences Limited | Manufacturing | 2023 |
| Rent Back Experts Limited | Extraterritorial | 2007 |
| Rentry Limited | Information & communication | 2014 |
| REO & Rens Ltd | Health & social care | 2015 |
| Replication Technologies Limited | Wholesale & retail | 1995 |
| Repton Consultancy Services Ltd | Information & communication | 2025 |
| Repton Park R a Limited | Other services | 2007 |
| Repton Property Management Limited | Real estate | 2021 |
| Resi Invest Limited | Professional & scientific | 2017 |
| Residential Care Providers Limited | Health & social care | 1997 |
| Residential Land 2 Limited | Financial services | 2017 |
| Residential Land 4 Limited | Other services | 2021 |
| Residential Land Equity Management Ltd | Financial services | 2014 |
| Residential Land Holdings Limited | Professional & scientific | 2006 |
| Residential Land Limited | Construction | 1987 |
| Residential Land Management 2 Ltd | Construction | 2010 |
| Residential Land Management 3 Limited | Administrative & support | 2014 |
| Residential Land Management 4 Limited | Construction | 2012 |
| Residential Land Management 5 Limited | Construction | 2014 |
| Residential Land Management Limited | Construction | 2006 |
| Restore Community | Health & social care | 2015 |
| Restore Community Church | Other services | 2001 |
| Restorer of Paths Limited | Professional & scientific | 2021 |
| Resul's Food & Wine Limited | Wholesale & retail | 2009 |
| Retail Banking Consultancy Ltd | Information & communication | 2014 |
| Retail Direct Limited | Other services | 2014 |