| Plane Tree Farm Services Limited | Billingham | 2024 |
| Planet Gardening Limited | Biggleswade | 2018 |
| Planet Trading Limited | Chipping Norton | 1999 |
| Planethon 365 UK Amazon CIC | London | 2024 |
| Plank Brothers Limited | Reading | 2011 |
| Planmac UK Limited | Bingley | 2006 |
| Planmajor Limited | Holmrook | 1988 |
| Plant a Tree Ltd | Coventry | 2021 |
| Plant Addict Ltd | Cambridge | 2023 |
| Plant an Oyster Ltd | Cowes | 2022 |
| Plant Breeding International Limited | Stratford-Upon-Avon | 2022 |
| Plant Collector Ltd | London | 2020 |
| Plant Ecology Beyond Land (Pebl) CIC | Swansea | 2019 |
| Plant Force (UK) Ltd | Liverpool | 2026 |
| Plant Force Britain Limited | London | 2025 |
| Plant Grow Share Ltd | Glasgow | 2021 |
| Plant Health Solutions Ltd | Warwick | 2010 |
| Plant House Ltd | Rotherham | 2025 |
| Plant One Cornwall Community Interest Company | Truro | 2021 |
| Plant Raisers 2005 Limited | Goole | 1999 |
| Plant Raisers Limited | Goole | 2004 |
| Plant Rescue Ltd | Hemel Hempstead | 2025 |
| Plant Revelations Limited | Rugeley | 2021 |
| Plant World Devon Ltd | Totnes | 2003 |
| Plant Your Future Trading Limited | Oxford | 2023 |
| Plant-Tech Innovations Limited | King''S Lynn | 2011 |
| Plant.Ng Wild Community Tree Nursery C.I.C. | Nottingham | 2023 |
| Plantae Limited | London | 2020 |
| Plantagation Ltd | Market Harborough | 2024 |
| Plantaigo Ltd | Manchester | 2023 |
| Plantara Ltd | Pontypridd | 2025 |
| Plantation Capital Limited | Fareham | 2008 |
| Plantation Farm Ltd | Tadley | 2010 |
| Plantations Lakes Ltd | Clevedon | 2023 |
| Plantbox Marine Ltd | London | 2026 |
| Plantex Connect Ltd | Canterbury | 2025 |
| Plantex Group Ltd | Canterbury | 2020 |
| Plantex Systems Ltd | Canterbury | 2025 |
| Plantgrow Ltd | Attleborough | 2009 |
| Planting Ideas Ltd | Stratford-Upon-Avon | 2016 |
| Plantinlab Ltd | Haywards Heath | 2023 |
| Plantm Limited | Cambridge | 2015 |
| Plantmetrics (UK) Limited | London | 2021 |
| Planton Farm Ltd | Ludlow | 2021 |
| Plantopia (N.I.) Ltd | Newtownards | 2018 |
| Plantosphere Ltd | Hamilton | 2023 |
| Plants 4 U Ltd | Tyne & Wear | 2003 |
| Plants and Minds | Bournemouth | 1989 |
| Plants for ALL Seasons Ltd | Leeds | 2019 |
| Plants for Nature Ltd | Colchester | 2025 |
| Plants Galore Horticulture Limited | Roydon | 2014 |
| Plantscape Tree Services Ltd | East Carleton | 2011 |
| Plas Bach Poultry Limited | Meifod | 2019 |
| Plas Contracting Limited | Porthmadog | 2012 |
| Plas Dolanog Ltd | Welshpool | 2019 |
| Plas Iolyn Ltd | Gyffin | 2021 |
| Plas Llanfair Limited | Holyhead | 2019 |
| Plas Llanfihangel CYF | Llangefni | 2015 |
| Plas Milk Limited | Llangefni | 2022 |
| Plas Newydd Ltd | Holyhead | 2020 |
| Plas Pedol CYF | Cardigan | 2025 |
| Plas Tirion Farm Limited | Tarporley | 2014 |
| Plasgwyn Farm Ltd | Carmarthen | 2009 |
| Plasterpitts Limited | Ripon | 1949 |
| Plasvacc UK Limited | Glasgow | 2022 |
| Platinum Bloodstock Ltd | London | 2026 |
| Platinum Retrievers Limited | Middlesbrough | 2021 |
| Platinum Services Ltd | Chislehurst | 2025 |
| Platinum Sport Horses Ltd | Gosport | 2018 |
| Platinum Stud Limited | Reading | 2023 |
| Platt Farms Ltd | Wells | 2015 |
| Platts Huneez Ltd | Aberystwyth | 2020 |
| Platts Specialist Services Ltd | Worksop | 2020 |
| Play by Nature Forest School Ltd | Runcorn | 2020 |
| Play PIT CIC | London | 2025 |
| Playatuna Ltd | Truro | 2024 |
| Playfair Farming Limited | Kelso | 2025 |
| Playle Construction Limited | Leicester | 2008 |
| Playters New Farm Limited | Beccles | 2022 |
| PLB Ecowood Limited | Barry | 2011 |
| PLB Ecowood South Limited | Cowbridge | 2022 |
| Pleasant Pastures Limited | Kington | 2023 |
| Pleasantview Limited | Barnoldswick | 2008 |
| Pleasure Marine UK Limited | Weeley | 2004 |
| Pledgdon Hall Farm Limited | Bishops Stortford | 2003 |
| Pleistocene Ltd | London | 2020 |
| Plena Terra Ltd | Twickenham | 2023 |
| Plenty Divitiae Trade Limited | Beckenham | 2024 |
| Plenty of KOI (Bristol) Limited | Bristol | 2022 |
| Plenty Sense Limited | Norwich | 2023 |
| Pleroma Limited | Co Tyrone | 1972 |
| Plessey Checks Farming Limited | Newcastle Upon Tyne | 2014 |
| PLF Farming Limited | Chippenham | 2023 |
| Plll Ltd | Ramsey | 2017 |
| PLM Agri & Livestocks Limited | Nuneaton | 2025 |
| Plockton Oyster Company Ltd | Plockton | 2021 |
| Plot 23 Ltd | Brixham | 2025 |
| Plot Keepers Limited | Letchworth Garden City | 2023 |
| Plots Farm Estate Ltd | Lincoln | 2022 |
| Ploughfield Farms Limited | Uckfield | 1972 |