| Proserco LLC Ltd | London | 2025 |
| Proserv Africa Limited | Westhill | 2026 |
| Prospect & Protocol Ltd. | Maidenhead | 2012 |
| Prospect Petroleum & Mineral Exploration Ltd | London | 2025 |
| Prospectiva Resources Ltd | Hemel Hempstead | 2025 |
| Prosperite MM1 Limited | Great Missenden | 2022 |
| Prospex Consulting Limited | Taunton | 2021 |
| Prospexgeo Limited | Hayle | 2025 |
| Protocol Exploration Limited | Lichfield | 2025 |
| Prusik Limited | Blackpool | 2021 |
| PSG Offshore Limited | Buckie | 2021 |
| PSL Energy Services Limited | Aberdeen | 2003 |
| PSR Oilfield Equipment Ltd | Leicester | 2003 |
| PST Energy Limited | Aberdeen | 2018 |
| PT Minerals Ltd | London | 2024 |
| Ptolemy Mining Limited | Amersham | 2022 |
| PTS Engineering Ltd | Dundee | 2018 |
| Pttep SP Limited | London | 1995 |
| Puffin Subsea Engineering Limited | Dumbarton | 2012 |
| Pulsar Helium (UK) Ltd | Bristol | 2021 |
| Pulsar Measuring Systems Limited | Steyning | 1988 |
| Pure and Green Earth Environmental Services Ltd | London | 2023 |
| Pure Engineers Limited | Bushey | 2024 |
| Pure Land 1 Ltd | London | 2024 |
| Puresalt Offshore Services Ltd | Birmingham | 2022 |
| Purple Dinosaur Geological Services Ltd | Eastbourne | 2015 |
| Purslow NDT Limited | Salford | 2022 |
| Putney Mining Ltd | Weybridge | 2016 |
| PW Enterprises Ltd | Leicester | 2018 |
| PWS Crew Limited | Banchory | 2016 |
| Pxog Marshall Limited | London | 2017 |
| Pxog Muirhill Limited | London | 2017 |
| Pynesfield Limited | West Drayton | 1996 |
| Pyott Offshore Ltd | Arbroath | 2026 |
| Pyxis Royalties Limited | London | 2021 |
| Q M Aggregate Contractors Limited | Felsted | 1990 |
| Q Stone Ltd | Glasgow | 2019 |
| QAI Consultants Limited | Hartlepool | 2017 |
| Qazmoly Limited | London | 2003 |
| QC Inspection Services Ltd | Plymouth | 2018 |
| QED International (UK) Limited | Aberdeen | 1987 |
| QED Technical Hub Limited | Basildon | 2023 |
| QEZ Ltd | Glasgow Central | 2023 |
| Qingdao Hanens Import and Export Co., Ltd | London | 2021 |
| Qingdao Ruixin Petroleum Equipment Manufacturing (UK) Ltd | Canterbury | 2022 |
| Qinghan Holding Liability Company Group Limited | Coventry | 2023 |
| QME Mining Services (NI) Limited | Newry | 2014 |
| QME Mining Services Limited | London | 2012 |
| QMR Services Ltd | Maidstone | 2023 |
| Qnex Energy Services Limited | London | 2023 |
| Quadriga Energy Limited | London | 2018 |
| Qualitas Energy Services Ltd | London | 2006 |
| Quality Fuels Ltd | Ammanford | 2003 |
| Quality NDT Inspection Ltd | Middlesbrough | 2012 |
| Qualitysafe Limited | Balerno | 2007 |
| Qualtech (Scotland) Ltd. | Peterhead | 1998 |
| Quanlin Intelligent Technology Co., Ltd | Stafford | 2022 |
| Quantum Xploration International Limited | London | 2023 |
| Quarries and Haulage Ltd | London | 2022 |
| Quarry Bros Ltd | Knutsford | 2025 |
| Quarry Industries Ltd | Belfast | 2022 |
| Quarry Manufacturing and Supplies Limited | Coalville | 1980 |
| Quarry Project Management Limited | Andover | 2019 |
| Quarry Recycling Parts Ltd | Omagh | 2022 |
| Quarryplan (GB) Limited | Downpatrick | 2009 |
| Quasands Energies Ltd | Reading | 2022 |
| Quattro Energy Limited | London | 2021 |
| Quay Marine Consultancy Limited | Dunoon | 2013 |
| Quest Petroleum Limited | Stonehaven | 2018 |
| Questra Energy Limited | London | 2024 |
| Quickstone Midlands Limited | Grantham | 1996 |
| Qwood Resources Ltd. | Binfield | 2018 |
| R & B Seafoods Limited | | 1993 |
| R & K (West Water) Limited | Turriff | 2000 |
| R & S Peck Ltd | Grangemouth | 2018 |
| R a Gower Geological Services Limited | Wickford | 2012 |
| R Bell Engineering Services Limited | Norwich | 2013 |
| R C Gower CSI & T Limited | Frinton-On-Sea | 2012 |
| R Farrell Plant Hire Limited | Halifax | 2008 |
| R G C (UK) Limited | Scarborough | 2006 |
| R H Geoconsultants Limited | Norfolk | 1999 |
| R H Tank Services Limited | Bicester | 2013 |
| R HAM Holdings Limited | Redcar | 2022 |
| R J & K Mackay Rigging Ltd | Tain | 2013 |
| R J Barclay Developments Ltd | Montrose | 2011 |
| R J H (Yorkshire) Limited | Ripon | 2009 |
| R L T T Services Limited | Montrose | 2014 |
| R M Global Services Limited | Cannock | 2016 |
| R Newton Services Ltd | Hamilton | 2019 |
| R S Aggregates Ltd | Swadlincote | 2020 |
| R S R L Ltd | Turriff | 2015 |
| R Spence Mechanical Limited | Blyth | 2024 |
| R W Evans & SON Limited | Brecon | 2005 |
| R&B Falcon (Caledonia) Limited | Birmingham | 1981 |
| R&B Falcon (U.K.) Limited | Birmingham | 1983 |
| R&R Access Ltd | London | 2026 |
| R. Hogg & Sons Limited | Toomebridge | 1957 |
| R.A.C. Consultants Ltd | Preston | 2011 |
| R.F Engineering Services Limited | Birmingham | 2004 |
| R.H. Roadstone Limited | Birmingham | 1985 |