| Q.I. Training Limited | Wholesale & retail | 1988 |
| QAP Trading Ltd | Hospitality | 2026 |
| QED Framing Ltd | Administrative & support | 1999 |
| Qexis Ltd | Information & communication | 2021 |
| QGM Consulting Limited | Professional & scientific | 2023 |
| Qiexe IT Ltd | Information & communication | 2019 |
| Qismat Stores UK PVT Ltd | Wholesale & retail | 2026 |
| QMN Trustees Limited | Financial services | 2016 |
| QMP Group Limited | Real estate | 2016 |
| QMP NO.1 Limited | Real estate | 2025 |
| QMP NO.2 Limited | Real estate | 2025 |
| QMP NO.3 Limited | Real estate | 2025 |
| QMP NO.4 Limited | Real estate | 2025 |
| QMP Rentals Limited | Real estate | 2018 |
| Qnap UK Limited | Information & communication | 2017 |
| Qooqs Operating Company Ltd | Wholesale & retail | 2024 |
| QPD Analytical Solutions Ltd | Professional & scientific | 2013 |
| Qrims Limited | Information & communication | 2003 |
| Qrnt Property Ltd | Construction | 2022 |
| Qrs-Associates Ltd | Professional & scientific | 2013 |
| QS Healthcare Limited | Health & social care | 2018 |
| Qsync Consultancy Ltd | Professional & scientific | 2025 |
| Qtec Services & Solutions Limited | Manufacturing | 2017 |
| Quackers Toys Limited | Wholesale & retail | 2025 |
| Quad Marketing Limited | Information & communication | 2014 |
| Quadpap Resourcing Ltd | Real estate | 2023 |
| Quadratiq Ltd | Financial services | 2025 |
| Quadrum Investments Group Limited | Professional & scientific | 2009 |
| Quality Advocate Limited | Professional & scientific | 2012 |
| Quality Bathroom Ltd | Construction | 2019 |
| Quality DRY Cleaner (UK) Ltd | Other services | 2013 |
| Quality Independent Car Traders Ltd | Wholesale & retail | 2025 |
| Quality Plus Locums Limited | Administrative & support | 2020 |
| Quality Smart Services Ltd | Transport & logistics | 2020 |
| Quantum Culture Ltd | Information & communication | 2024 |
| Quantum Mindset Associates Ltd | Administrative & support | 2023 |
| Quantum Twenty One Ltd | Information & communication | 2019 |
| Quattro Home Solutions Ltd | Construction | 2025 |
| Quattro Technology Ltd | Professional & scientific | 1997 |
| Qubit Tangle Ltd | Information & communication | 2025 |
| Queensgate Management Swindon Limited | Households | 2004 |
| Quercus (RWB) Limited | Hospitality | 2023 |
| Quercus Bistro (Devizes) Ltd | Hospitality | 2026 |
| Quercy Holdings Limited | Financial services | 2021 |
| Queston Ltd | Administrative & support | 2023 |
| Quick Move NOW Limited | Real estate | 1998 |
| Quick Move Properties Limited | Real estate | 2014 |
| Quick Stop Regent Ltd | Wholesale & retail | 2025 |
| Quick Taxi Ltd | Transport & logistics | 2026 |
| Quick Time Recoveries Ltd | Construction | 2024 |
| Quick Time Solutions Ltd | Extraterritorial | 2021 |
| Quick Wash Hand Car Wash Ltd | Administrative & support | 2025 |
| Quickfire Heating Ltd | Construction | 2024 |
| Quickprime Ltd | Wholesale & retail | 2023 |
| Quickskills Ltd | Professional & scientific | 2025 |
| Quicksoft Limited | Other services | 2017 |
| Quicktile Limited | Administrative & support | 2010 |
| Quicktime Transport Ltd | Transport & logistics | 2017 |
| Quidwai Engineering Ltd | Professional & scientific | 2022 |
| Quiet Waters Consulting Limited | Information & communication | 2022 |
| Quinn & Jones Construction Limited | Construction | 2002 |
| Quinn Whitfield Limited | Information & communication | 2013 |
| Quins Specialist Cars Limited | Wholesale & retail | 2003 |
| Quintress Ltd | Transport & logistics | 2024 |
| Quipu Limited | Information & communication | 1990 |
| Quirk & Key Limited | Real estate | 2023 |
| R & a 4X4 Services Limited | Wholesale & retail | 2014 |
| R & B Auto's Swindon Ltd | Wholesale & retail | 2024 |
| R & H Interiors Limited | Construction | 2000 |
| R & J Pearce Limited | Construction | 2001 |
| R & M Plumbing Limited | Construction | 2018 |
| R & R Design and Build Contractors Limited | Construction | 2020 |
| R & R Reinforcement Ltd | Construction | 2024 |
| R & S Care Swindon Limited | Health & social care | 2021 |
| R & S Group (Swindon) Ltd | Construction | 2017 |
| R and M Houses Ltd | Real estate | 2023 |
| R and R UK Automation Ltd | Manufacturing | 2017 |
| R Business Solution Ltd | Wholesale & retail | 2025 |
| R Byrne Holdings Limited | Financial services | 2026 |
| R C Anaesthetic Services Limited | Health & social care | 2010 |
| R C Pharma Limited | Financial services | 2018 |
| R C Services Limited | Wholesale & retail | 2003 |
| R Clarkes Customs Ltd | Wholesale & retail | 2025 |
| R H Pharma Limited | Wholesale & retail | 2010 |
| R Heyes Social Work Assessments Ltd | Health & social care | 2022 |
| R J Crapper Holdings Ltd | Financial services | 2025 |
| R J Neville Limited | Professional & scientific | 1983 |
| R J Plant Limited | Administrative & support | 2013 |
| R K Infosol Limited | Information & communication | 2013 |
| R K Rigging Limited | Information & communication | 2022 |
| R L Electrical (Swindon) Ltd | Construction | 2018 |
| R P Emery Limited | Construction | 2005 |
| R P Sheldon Ltd | Professional & scientific | 2018 |
| R Pearce Construction Limited | Construction | 2018 |
| R&A Barbers Ltd | Other services | 2024 |
| R&A Development (Wiltshire) Limited | Real estate | 2011 |
| R&D Housemartin Limited | Real estate | 2013 |
| R&H Electric (HO) Limited | Wholesale & retail | 2008 |
| R&O Transport Ltd | Transport & logistics | 2025 |
| R&R Investco Ltd | Real estate | 2025 |