| Putti Cakes Consulting Ltd | Information & communication | 2018 |
| Puur Limited | Administrative & support | 2007 |
| PVL Estate Limited | Construction | 2025 |
| PVZ Holdings Limited | Real estate | 2023 |
| PWD Roofing and Building Ltd | Construction | 2025 |
| Pwlc Partners Ltd | Transport & logistics | 2016 |
| Pwlc Projects LLP | | 2016 |
| PWR Software Ltd | Information & communication | 2019 |
| PY Prosthodontics Limited | Health & social care | 2026 |
| Pyaano Ltd | Hospitality | 2026 |
| Pyaar Investments Limited | Financial services | 2021 |
| Pyramidx Limited | Construction | 2019 |
| Pyro Property Holdings UK Limited | Real estate | 2022 |
| Pyxsis Services Ltd | Professional & scientific | 2019 |
| Q & Q Management Limited | Real estate | 2020 |
| Q Beds Ltd | Wholesale & retail | 2024 |
| Q Homes Limited | Construction | 2011 |
| Q Shaw Limited | Professional & scientific | 2017 |
| Q&Q Handyman Ltd | Construction | 2023 |
| Q-Audio (Products) Limited | Arts & recreation | 2007 |
| Q-Media Group | Education | 2017 |
| Q-Online Limited | Professional & scientific | 2011 |
| Q.M. Dhillon & Sons (UK) Ltd | Real estate | 2016 |
| QA Tech Consultancy Ltd | Information & communication | 2018 |
| Qaardan Care Hub Limited | Health & social care | 2024 |
| Qadop Ltd | Information & communication | 2022 |
| Qahorizon Limited | Information & communication | 2013 |
| Qandil Trasport Ltd | Transport & logistics | 2026 |
| Qatar Hydraulic UK Ltd | Wholesale & retail | 2022 |
| QAZ International Ltd | Other services | 2017 |
| QBB Production Ltd | Information & communication | 2018 |
| Qbwr Construction Limited | Construction | 2024 |
| QCD Holdings Ltd | Financial services | 2019 |
| QH Estates Ltd | Real estate | 2011 |
| QI Financial Solutions Limited | Financial services | 2000 |
| Qibdil Ltd | Wholesale & retail | 2026 |
| Qifar Management Limited | Construction | 2020 |
| Qingdao Bolun Auto Parts Co., Ltd | Wholesale & retail | 2024 |
| QK Meats (Kent) Ltd | Wholesale & retail | 2024 |
| Qmark Development Limited | Real estate | 2016 |
| QML Properties Ltd | Real estate | 2024 |
| Qornerstone Limited | Health & social care | 2020 |
| QQ Properties Limited | Real estate | 2018 |
| Quadrangle Residents Limited | Households | 2002 |
| Quadrant Bespoke Limited | Wholesale & retail | 2024 |
| Quadric Services Ltd | Information & communication | 2024 |
| Qualia Lounge Limited | Hospitality | 2022 |
| Quality Booze Ltd | Wholesale & retail | 2021 |
| Quality Care Homes (UK) Limited | Health & social care | 2005 |
| Quality Code Muse Ltd | Information & communication | 2025 |
| Quality Engineered Ltd | Information & communication | 2019 |
| Quality Investment Solutions Limited | Administrative & support | 2007 |
| Quality Investor Packs Limited | Professional & scientific | 2018 |
| Quality Legal Solutions Ltd | Professional & scientific | 2019 |
| Quality Seafood London Limited | Wholesale & retail | 2017 |
| Quantis Solutions Limited | Information & communication | 2026 |
| Quantum (Barrowsfield) Ltd | Administrative & support | 2019 |
| Quantum (Flimwell) Ltd | Administrative & support | 2017 |
| Quantum (Grays) Management Company Limited | Households | 2013 |
| Quantum (Pollards Hill) Ltd | Administrative & support | 2019 |
| Quantum Aggregates Ltd | Water & waste | 2014 |
| Quantum Change Consulting Ltd | Other services | 2010 |
| Quantum Design & Build Ltd | Construction | 2015 |
| Quantum Group Ltd | Financial services | 2015 |
| Quantum Land & Planning Ltd | Administrative & support | 2014 |
| Quantum Leap Solutions Ltd | Information & communication | 2013 |
| Quantum Strategy International LLP | | 2021 |
| Quantum Strategy Limited | Real estate | 2008 |
| Quarry Place Management Limited | Households | 1984 |
| Quartzstar Limited | Households | 2001 |
| Quay 56 Management Company Limited | Households | 1990 |
| Quays Quality Building Services Limited | Construction | 2017 |
| QUE Omen Ltd. | Wholesale & retail | 2022 |
| Queens Court (Heaton Mersey) Management Company Limited | Households | 1988 |
| Queensbury Place Management Company (Cheam) Limited | Extraterritorial | 2014 |
| Queer Jazz Ltd | Arts & recreation | 2024 |
| Quick Contracts Limited | Construction | 2006 |
| Quick FIX Auto Parts and Car Services Ltd | Wholesale & retail | 2021 |
| Quick Flow Plumbing & Heating Ltd | Construction | 2010 |
| Quick Mark Solutions Ltd | Education | 2024 |
| Quick Nest by J & H Limited | Real estate | 2025 |
| Quick Repair Autos Ltd | Wholesale & retail | 2023 |
| Quick Response Cctv Ltd | Health & social care | 2008 |
| Quick Snackz Limited | Hospitality | 2025 |
| Quick Tech Solution Ltd | Other services | 2018 |
| Quickorbit Ltd | Wholesale & retail | 2025 |
| Quickpack and Move Limited | Transport & logistics | 2025 |
| Quicksilver Flues Limited | | 1987 |
| Quickview Construction Ltd | Construction | 2014 |
| Quidie Limited | Financial services | 2012 |
| Quiet Giant Ltd | Health & social care | 2009 |
| Quiet Storm Music Ltd | Wholesale & retail | 2025 |
| Quik Share Ltd | Wholesale & retail | 2025 |
| Quince Properties Limited | Real estate | 2001 |
| Quincy Road Management Company Ltd | Households | 2009 |
| Quinse Limited | Real estate | 2025 |
| Quinta Keep Ltd | Real estate | 2019 |
| Quiscit Ltd | Information & communication | 2019 |
| Quiva Transfers Ltd | Administrative & support | 2020 |
| Quolour Limited | Professional & scientific | 2019 |