| Pyecam Company Limited | Professional & scientific | 1977 |
| Pyrix Ltd | Wholesale & retail | 2025 |
| Q -Aura Ltd | Arts & recreation | 2020 |
| Qacnc Limited | Manufacturing | 1996 |
| Qbox Corp Ltd | Other services | 2022 |
| Qftech Ltd. | Information & communication | 2011 |
| Qinetic Limited | Professional & scientific | 2006 |
| Qinetiq Estates Limited | Extraterritorial | 2001 |
| Qinetiq Group Holdings Limited | Professional & scientific | 2010 |
| Qinetiq Group PLC | Professional & scientific | 2002 |
| Qinetiq Holdings Limited | Administrative & support | 2001 |
| Qinetiq Limited | Professional & scientific | 1999 |
| Qinetiq Overseas Holdings Limited | Professional & scientific | 2002 |
| Qinetiq Overseas Trading Limited | Administrative & support | 2007 |
| Qinetiq Pension Scheme Trustee Limited | Other services | 2012 |
| Qinetiq Target Services Limited | Professional & scientific | 2006 |
| Qinetiq Target Systems Limited | Manufacturing | 1985 |
| Qinetiq Training and Simulation Limited | Information & communication | 1988 |
| Qritikal Limited | Information & communication | 2017 |
| Qserve Group UK Ltd | Professional & scientific | 2019 |
| QSX Technology Limited | Information & communication | 1989 |
| Quality A/C Limited | Construction | 2023 |
| Quality Garden Offices Ltd | Construction | 2020 |
| Quality Living at Home Limited | Health & social care | 2021 |
| Quantum Decorating Services Ltd | Construction | 2024 |
| Quarterdeck Solutions Limited | Hospitality | 2018 |
| Queensway Carpentry Ltd | Administrative & support | 2006 |
| Quinntessential Enterprise Limited | Administrative & support | 2007 |
| Quite Vocal Limited | Information & communication | 2016 |
| Quokka Education Ltd | Administrative & support | 2025 |
| Quotalys Limited | Administrative & support | 2002 |
| R & G Fresh Herbs | Manufacturing | 2018 |
| R & G Ventures Limited | Real estate | 2018 |
| R & R Omega Ltd | Construction | 2022 |
| R J a (UK) Limited | Administrative & support | 2001 |
| R&B CNC Ltd | Manufacturing | 2021 |
| R&S Brothers Ventures Limited | Real estate | 2026 |
| R. Brooks Electrical Services Limited | Construction | 2001 |
| R.A.B. Global Limited | Manufacturing | 2009 |
| R.B. Construction (LDN) Limited | Construction | 2016 |
| R.C. Grant & Sons Limited | Administrative & support | 1998 |
| R2 Cleaning & Maintenance LLP | | 2024 |
| RA Autos Mobile Mechanic Limited | Wholesale & retail | 2021 |
| RAA Capital Ltd | Financial services | 2017 |
| RAA Partners Ltd | Real estate | 2022 |
| RAA Planning Ltd | Real estate | 2017 |
| RAA3 Ltd | Real estate | 2024 |
| RAA7 Ltd | Real estate | 2024 |
| Rabbit and Dowling Plant Hire Limited | Administrative & support | 1999 |
| Radiant Party Decor Ltd | Arts & recreation | 2024 |
| RAE Inspirations Ltd | Health & social care | 2019 |
| Rags Hall Farm Ltd | Real estate | 2013 |
| Raheja Realventures Limited | Real estate | 2024 |
| Rahib CAB Services Ltd | Transport & logistics | 2025 |
| Rainbow Technologies Limited | Real estate | 2009 |
| Raindrop Limited | Administrative & support | 2018 |
| Raise Professionals Ltd | Information & communication | 2022 |
| RAJ Cluster Limited | Wholesale & retail | 2009 |
| RAM Power UK Services Ltd | Construction | 2021 |
| Ranas Hub Ltd | Wholesale & retail | 2024 |
| Rang London Ltd | Wholesale & retail | 2022 |
| Rapallo Close Management Company Limited | Households | 1979 |
| Rapid Returns Limited | Real estate | 2020 |
| Rapid Space Technologies Ltd | Transport & logistics | 2011 |
| Rasmaya Ltd | Hospitality | 2020 |
| Rastra Accountants Limited | Professional & scientific | 2025 |
| Ratchet Straps UK Ltd | Wholesale & retail | 2016 |
| Raven Applied Intelligence Limited | Manufacturing | 2026 |
| RAW Gold Media Ltd | Information & communication | 2009 |
| Razorfish Ltd | Information & communication | 2019 |
| RBR Decorating Limited | Construction | 2008 |
| RBS Account and Tax Consultation Ltd | Education | 2012 |
| RD Construction & Property Services Ltd | Construction | 2026 |
| RD Worldwide Ltd | Wholesale & retail | 2018 |
| RDF Electrical Ltd | Manufacturing | 2020 |
| RDM (UK) Limited | Wholesale & retail | 2007 |
| RE Flooring Works Limited | Construction | 2025 |
| Rebelvend UK Limited | Wholesale & retail | 2015 |
| Red Clay Media Agency Limited | Professional & scientific | 2024 |
| Red Cube Events Ltd | Hospitality | 2018 |
| Red Electrical Contracting Services Ltd | Construction | 2009 |
| Red House Property Holdings Ltd | Real estate | 2026 |
| Red Oak Property Investment Ltd | Financial services | 2022 |
| Red Rooster Graphic Design Company Ltd | Administrative & support | 2005 |
| Redan Residents Association Limited | Households | 1983 |
| Rede Court Residents Association Limited | Real estate | 1993 |
| Redinvest Limited | Construction | 1986 |
| Redsky Support Services (UK) Limited | Administrative & support | 2014 |
| Redspace Ltd | Professional & scientific | 2023 |
| Redstripes the Barbers Ltd | Other services | 2026 |
| Redteq Analytical Ltd | Manufacturing | 2013 |
| Redwing Estates (Andover) Limited | Construction | 1991 |
| Redwing Estates (Nuneaton) Limited | Real estate | 2001 |
| Redwing Estates Limited | Construction | 1988 |
| Redwood Group Ltd | Construction | 2018 |
| Redy Inc Ltd | Construction | 2019 |
| REE Marketing Ltd | Administrative & support | 2025 |
| Rees Homes Limited | Construction | 2003 |
| Reflex Courier & Freight Solutions Limited | Transport & logistics | 2012 |
| Refract Technologies Ltd | Information & communication | 2025 |