| M J Wood Solutions Limited | Haywards Heath | 2006 |
| M K Property Developers Limited | Dewsbury | 2012 |
| M Keeling Farming Ltd | Frome | 2020 |
| M Knight Forestry and Civil Site Clearance Ltd | Kettering | 2014 |
| M L L (Shetland) Ltd | Shetland | 2014 |
| M L Smith & Sons Ltd | Spalding | 2011 |
| M Large Limited | Newtownabbey | 2017 |
| M Large Tree Services Limited | Newtownabbey | 1992 |
| M Lloyd Services Ltd | Whitchurch | 2022 |
| M M Self Ltd | Ipswich | 2013 |
| M Mackenzie Services Ltd | Thurso | 2025 |
| M Madders Farming Limited | Staffordshire | 2008 |
| M Metcalfe Contracting Limited | Richmond | 2015 |
| M Morris Contracting Limited | Kidderminster | 2024 |
| M Naylor Enterprises Ltd | Wickford | 2018 |
| M New Contracting Ltd | Darlington | 2021 |
| M Nicholson Limited | Carlisle | 2007 |
| M O S Nature UK Ltd | Inverurie | 2019 |
| M P & E Leigh-Firbank Limited | Sturminster Newton | 2007 |
| M P Harris Contracting Ltd | Bury St. Edmunds | 2024 |
| M P Wright Ltd | Ashbourne | 2013 |
| M Peck Contracting Limited | Harleston | 2023 |
| M Potts Tree Services Limited | Wakefield | 2015 |
| M R Durrans Fishing Ltd | Newton Abbot | 2003 |
| M R E & B a Hawker Limited | Chippenham | 2009 |
| M R G Taylor Limited | Taunton | 1992 |
| M R Hendy Limited | Wellington | 2002 |
| M R Jibson Farmer | York | 2002 |
| M R L (Shropshire) Ltd | Wrexham Technology Park | 2018 |
| M R Tizzard Limited | Sherborne | 2008 |
| M R Young & Sons (Rural) Limited | Swindon | 2012 |
| M Raynor Crop Consultants Limited | Honiton | 2003 |
| M Raywood Ltd | Carlisle | 1974 |
| M Read Game Limited | Halesworth | 2019 |
| M Rees Limited | East Preston | 2013 |
| M Reid & Sons | Dumfries | 2004 |
| M Rudge Tree Services Limited | Kidlington | 2012 |
| M Russell Tree Specialists Ltd | Emsworth | 2015 |
| M S Contracting Ltd | Melton Mowbray | 2006 |
| M S Dunster Groundworks Ltd | Taunton | 2010 |
| M S Frenchies UK Ltd | Burton-On-Trent | 2022 |
| M S Vernon Limited | Darlington | 2014 |
| M Salter & SON Limited | Honiton | 2015 |
| M Sutherland Contracting Ltd. | Alness | 2024 |
| M T Commercial Fishing Limited | Hastings | 2020 |
| M T Equipment Limited | Wiltshire | 2003 |
| M Tester & S Edwards Ltd | Tiverton | 2024 |
| M Toms Plant & Enginnering Ltd | Launceston | 2009 |
| M Triggs & SON Limited | Wirral | 2010 |
| M V Silver Fern Ltd. | | 2002 |
| M W Coombes Limited | Bridgwater | 2012 |
| M W Fisher Agriservices Limited | Cumbria | 2003 |
| M W Pigs Limited | Richmond | 2018 |
| M W S Fishing Ltd | London | 2013 |
| M W Services SOT Ltd | Stoke-On-Trent | 2021 |
| M W Snare Plant Hire Limited | Norwich | 2011 |
| M Watts Countryside Contracting Limited | Bristol | 2017 |
| M Weaver Limited | Stone | 2014 |
| M Welby Ltd | Petersfield | 2019 |
| M Whitehouse Contractors Limited | Stoke On Trent | 2018 |
| M Winterbottom Limited | Glossop | 2015 |
| M Y Services Southwest Ltd | Wellington | 2025 |
| M&A Combined Limited | Glasgow | 2018 |
| M&B Humphry Ltd | Taunton | 2023 |
| M&C Agri Services Ltd | Peterborough | 2021 |
| M&C Racing , PRE Training & Rehabilitation Limited | Cheltenham | 2025 |
| M&E Farm Limited | Bideford | 2023 |
| M&E Landscaping & Clivi Ltd | Motherwell | 2026 |
| M&G Cash Ltd | Carlisle | 2019 |
| M&G Mushrooms Limited | Armagh | 2016 |
| M&G Paulson Limited | Retford | 2012 |
| M&G Trading Ltd | Milton Keynes | 2020 |
| M&H Stewart Farms Ltd | Ballyclare | 2020 |
| M&J Hoofcare Ltd | Leeds | 2018 |
| M&J Hotel Ltd | Chadderton | 2023 |
| M&J Norquay Holdings Ltd | Orkney | 2026 |
| M&K Bloodstock Limited | Farnborough | 2022 |
| M&L Trawlers Limited | Brixham | 2007 |
| M&L Wiles Ltd | Birmingham | 2025 |
| M&M Poultry Limited | Leominster | 2015 |
| M&O Storage Limited | Northwood | 2018 |
| M&P Resources Ltd | Horsham | 2021 |
| M&S Parratt Livestock Limited | Colchester | 2003 |
| M&S Trees Limited | Farnham | 2018 |
| M&W.A16PALLETS Ltd | Spalding | 2025 |
| M&Y Tewkesbury Ltd | Tewkesbury | 2019 |
| M-W-Architectural Ltd | Alton | 2023 |
| M. & R. Kirkham & Sons Limited | Solihull | 1979 |
| M. and C.Farms Limited | Rye | 1940 |
| M. and J. S. Youdan Limited | Nr Doncaster | 1963 |
| M. Bailey Tree Services Limited | Burton-On-Trent | 2016 |
| M. Bruce & Partners Limited | Ellon | 1995 |
| M. Dent Farming Limited | Darlington | 2015 |
| M. E. Agri Ltd | Devizes | 2015 |
| M. E. Claxton & Sons Limited | Bury St Edmunds | 2025 |
| M. Farnsworth Limited | Danbury | 1983 |
| M. Forbes Farming & Fishing Ltd | Tain | 2022 |
| M. H. Petch Limited | Middlesbrough | 1984 |
| M. H. Rains Limited | King'S Lynn | 1999 |
| M. Higgins Limited | Doncaster | 1979 |