| Qasym Ltd | Administrative & support | 2024 |
| Qbaccountants Ltd | Extraterritorial | 2017 |
| QC Consultancy & Services Ltd | Manufacturing | 2012 |
| Qiconsult Ltd | Professional & scientific | 2024 |
| QMR Consultants Ltd | Information & communication | 2018 |
| QN2M Ltd | Health & social care | 2025 |
| Qnect.Ai Ltd | Information & communication | 2025 |
| Qortuba Capital Ltd | Real estate | 2025 |
| Qosmic Studio Limited | Professional & scientific | 2025 |
| QPS Construction Ltd. | Construction | 2003 |
| QS Copilot Ltd | Other services | 2018 |
| Qtrix Ltd | Information & communication | 2015 |
| Quadir Trading Limited | Manufacturing | 1976 |
| Quadrant Evictions Limited | Other services | 2019 |
| Quadrant Heating & Electrics Limited | Construction | 2022 |
| Quadrant Heating & Plumbing Ltd | Construction | 2023 |
| Qualitas Consortium UK Limited | Administrative & support | 2015 |
| Quality Care Approval Scheme Community Interest Company | Health & social care | 2021 |
| Quality Creation Limited | Health & social care | 2019 |
| Quality Dryliners Ltd | Construction | 2017 |
| Quality Inxs Ltd | Wholesale & retail | 2020 |
| Qualityhandcraft Ltd | Wholesale & retail | 2021 |
| Quantitative Recruiters Ltd | Administrative & support | 2021 |
| Quantulus Limited | Professional & scientific | 2002 |
| Quantum CMS 786 Limited | Professional & scientific | 2023 |
| Quantum CMS FND CIC | Information & communication | 2025 |
| Quantum Liquidity Systems Ltd | Information & communication | 2025 |
| Quantum Vitality Limited | Manufacturing | 2025 |
| Quarrydale Consulting Ltd | Information & communication | 2022 |
| Quatro Holdings Limited | Financial services | 2023 |
| Qube Resin Limited | Construction | 2017 |
| QUE Health Limited | Health & social care | 2017 |
| QUE Technologies Limited | Information & communication | 2008 |
| Quebec Enterprise Ltd | Transport & logistics | 2022 |
| Queen BEE Honey & Cosmetics Ltd | Wholesale & retail | 2024 |
| Queen Eleanor's Heights Residents Association Limited | Extraterritorial | 2002 |
| Queens Acre (High Wycombe) Management Company Limited | Households | 1996 |
| Queens Court (High Wycombe) Limited | Households | 1973 |
| Queensgate House Management Company Limited | Households | 2006 |
| Quench Dispensers Limited | Professional & scientific | 1974 |
| Quench Limited | Professional & scientific | 2008 |
| Quest Group of Companies Limited | Real estate | 2015 |
| Quest Sports Ltd | Education | 2024 |
| Questcost Limited | Professional & scientific | 2000 |
| Questions Matter Ltd | Professional & scientific | 2025 |
| Quex Mews Management Ltd | Households | 2012 |
| Quick Auto Valeting Services UK Limited | Administrative & support | 2015 |
| Quick Fresh Ltd | Hospitality | 2016 |
| Quick Property Solutions London Ltd | Real estate | 2024 |
| QUICK4YOU Limited | Wholesale & retail | 2016 |
| Quickbet Limited | Information & communication | 2025 |
| Quickcold Ltd | Manufacturing | 2022 |
| Quicklime Limited | Wholesale & retail | 2019 |
| Quickparts UK Ltd | Administrative & support | 2021 |
| Quicksmart Ltd | Wholesale & retail | 2008 |
| Quills Tutorials Limited | Extraterritorial | 2015 |
| Quintus Systems Limited | Manufacturing | 1995 |
| Quis Custodiet Limited | Professional & scientific | 2021 |
| Qul-Ahad Enterprise Ltd | Hospitality | 2023 |
| Quora Consulting Limited | Information & communication | 2013 |
| Quranic Ascent Ltd | Education | 2025 |
| Qureshi Property Ltd | Real estate | 2020 |
| Qurhus Services Limited | Financial services | 2019 |
| Qwerty Consultants Limited | Professional & scientific | 2018 |
| R & C Ventures Ltd | Professional & scientific | 2019 |
| R & D Patel Ltd | Wholesale & retail | 2023 |
| R & J Homes Development Limited | Construction | 2018 |
| R & J Trade Limited | Hospitality | 2018 |
| R & L Glow Studio Ltd | Other services | 2025 |
| R & O Estates Ltd | Real estate | 2023 |
| R a Jones (Project Management) Ltd | Construction | 2026 |
| R B Autos Contracts Ltd | Administrative & support | 1996 |
| R C P Telecommunications Consultants Limited | Information & communication | 1992 |
| R Draper Electrical Limited | Construction | 2017 |
| R F D M (London) Ltd | Construction | 2011 |
| R H Packaging Limited | Wholesale & retail | 1991 |
| R I K Logistic Services Ltd | Wholesale & retail | 2026 |
| R J B Marketing Limited | Wholesale & retail | 2000 |
| R Patel Foods Global Ltd | Wholesale & retail | 2026 |
| R Sawhney Properties Ltd | Real estate | 2021 |
| R&A Developers Ltd | Construction | 2020 |
| R&D Waste Removal Ltd | Water & waste | 2024 |
| R&R IT Solutions Ltd | Information & communication | 2014 |
| R&R Painting & Decorating Limited | Construction | 2023 |
| R&R Property Limited | Real estate | 2020 |
| R&R Trade Cars Ltd | Wholesale & retail | 2022 |
| R&R Wright Investments Ltd | Administrative & support | 2020 |
| R&V Roofing Construction Ltd | Construction | 2024 |
| R. a. G. Flynn Limited | Real estate | 2024 |
| R.G.B. Employees Beneficial Trust Limited | Professional & scientific | 1957 |
| R.H.Amar & Co Limited | Administrative & support | 1951 |
| R.K Electric Ltd | Construction | 2019 |
| R.P.W. Limited | Financial services | 2005 |
| R.T. Martin & SON Limited | Construction | 2003 |
| R.Watkins Ltd. | Information & communication | 2025 |
| R2SA Masters Limited | Real estate | 2022 |
| R3VIVAL Records Ltd | Information & communication | 2024 |
| Raabta Property Investments Ltd | Real estate | 2023 |
| Raaj Darbaar Ltd | Hospitality | 2023 |
| Rabia Kamran Ltd | Wholesale & retail | 2025 |