| Land & Lakes (Anglesey) Limited | Real estate | 2010 |
| Land and Lakes (Cumbria) Limited | Real estate | 2009 |
| Langrigge House (North) Management Company Limited | Households | 2012 |
| Larkrigg Garage Ltd | Wholesale & retail | 2015 |
| Lefton Properties Limited | Real estate | 2021 |
| Lesketh HOW Management Company Limited | Households | 2018 |
| Life Saving Solutions UK Ltd | Professional & scientific | 2024 |
| Limoncello Windermere Limited | Hospitality | 2020 |
| Lingmoor Hamlet Management Limited | Real estate | 1983 |
| London Climbing Walls Limited | Arts & recreation | 2021 |
| Lonestar Advertising Limited | Administrative & support | 2002 |
| Lontime Hotel Co., Ltd. | Hospitality | 2019 |
| Lorian Properties Limited | Real estate | 1994 |
| LOW Moor Howe Farm Limited | Agriculture & fishing | 1981 |
| Luchie Limited | Wholesale & retail | 2023 |
| Lucky Dragon Chinese Takeaway Ltd | Hospitality | 2016 |
| Lukas Partners Ltd | Professional & scientific | 2014 |
| LUX Lake District Ltd | Other services | 2026 |
| Lynstead (Windermere) Residents Association Limited | Households | 1994 |
| M&M Bowness Ltd | Hospitality | 2015 |
| Mabel & MU Ltd | Wholesale & retail | 2017 |
| Machell Limited | Construction | 2013 |
| Magennis Plumbing and Heating Ltd | Construction | 2019 |
| Maho Catering Ltd | Hospitality | 2017 |
| Maid in the Lakes Ltd | Administrative & support | 2025 |
| Make IT Better Ltd | Professional & scientific | 2023 |
| Make Specialist Manufacture and Installation Limited | Manufacturing | 2014 |
| Mandarin Lakes Ltd | Professional & scientific | 2025 |
| Mark Howarth Building Contractors Ltd | Construction | 2022 |
| Mark Martin Garden Services Limited | Other services | 2025 |
| Marshall Radio Telemetry Limited | Information & communication | 2019 |
| Marvic Management Company Limited | Real estate | 2008 |
| Matrosie Limited | Hospitality | 2021 |
| Matthews Benjamin Lettings Ltd | Real estate | 2018 |
| Matthews Benjamin Limited | Real estate | 2001 |
| MAX Turner Adventures Limited | Other services | 2021 |
| MAX Turner Properties Limited | Other services | 2023 |
| MBE Accountancy Ltd | Professional & scientific | 2015 |
| Mcfilmsuk Limited | Extraterritorial | 2024 |
| Mela Spice Fusion Limited | Hospitality | 2009 |
| Mere Local Convenience Store Ltd | Wholesale & retail | 2025 |
| Mere Local Store Ltd | Wholesale & retail | 2024 |
| Mere Property Services Limited | Construction | 2025 |
| Merewood Lodge Management Company Limited | Households | 2001 |
| Mhhm (UK) Ltd | Hospitality | 2014 |
| MIA & Mere Ltd | Hospitality | 2026 |
| Micklemoss Lodges Limited | Hospitality | 2017 |
| Middle Entrance Drive Associates Limited | Real estate | 2016 |
| Miller Howe Hotel | | 2002 |
| Miramar Management Company Limited | Households | 2001 |
| Miss Kirsty's Performers CIC | Arts & recreation | 2026 |
| MJP Business Limited | Manufacturing | 2020 |
| MND Accountancy Limited | Professional & scientific | 2009 |
| Moore & Co Butchers Limited | Wholesale & retail | 2025 |
| Mountain Goat Garage Limited | Wholesale & retail | 2015 |
| Mountain Goat Limited | Administrative & support | 1993 |
| MOX & Munchies Ltd | Wholesale & retail | 2025 |
| MRP Retail Cumbria Limited | Wholesale & retail | 2024 |
| MRS B'S Bakehouse Ltd | Wholesale & retail | 2025 |
| Mrxh Ltd | Professional & scientific | 2024 |
| Mtcs (UK) Ltd | Professional & scientific | 2003 |
| Murphy's Hot Sauce Ltd | Manufacturing | 2025 |
| Mushroomsynth Ltd | Wholesale & retail | 2026 |
| Musicman Productions Limited | Professional & scientific | 1997 |
| Must Management Limited | Hospitality | 2025 |
| Mylnbeck Flats (Windermere) Limited | Households | 1960 |
| Naik Media Ltd | Professional & scientific | 2020 |
| National Park Print Shop Limited | Wholesale & retail | 2021 |
| Neaum Catering Services Limited | Hospitality | 2026 |
| Neaum Hospitality Ltd | Hospitality | 2020 |
| Nemus Group Ltd | Wholesale & retail | 2026 |
| Nice and Associates LLP | | 2006 |
| Nicoh Consulting Ltd | Professional & scientific | 2022 |
| Nicoh Limited | Real estate | 2021 |
| Nielsen House Design Ltd | Professional & scientific | 2023 |
| Nikki Hayton Ltd | Real estate | 2014 |
| Nine Oaks Housing Trust Limited | Hospitality | 1969 |
| NM Airport Transfers Ltd | Transport & logistics | 2025 |
| NO. 5 Belsfield Ltd | Real estate | 2024 |
| Nomad Events Ltd | Hospitality | 2012 |
| Northern Earthworks Ltd | Construction | 2025 |
| Northwest Coffee House Ltd | Hospitality | 2018 |
| Northwest Technology Ltd | Other services | 2006 |
| Norwest Quarries Limited | Transport & logistics | 1995 |
| Norwood 1875 Ltd | Real estate | 2026 |
| Nsnrg Ltd | Energy | 2015 |
| O R G (Windermere) Limited | Wholesale & retail | 2018 |
| Oakdene Software Limited | Information & communication | 2011 |
| Oakthwaite Garages Limited | Hospitality | 2020 |
| Oakthwaite Holdings Limited | Households | 2026 |
| Oakwood Farm Bakery Ltd | Manufacturing | 2025 |
| OCTOPUS3 CIC | Professional & scientific | 2025 |
| Old College (Windermere) Limited | Households | 1998 |
| Oldfield Properties (Windermere) Limited | Hospitality | 2021 |
| Omnia Leather (Windermere) Ltd | Wholesale & retail | 2024 |
| Operation Groombridge Ltd | Information & communication | 2022 |
| Orrest Head Cleaning Ltd | Administrative & support | 2021 |
| Outlet Store Windermere Ltd | Wholesale & retail | 2025 |
| P. & D. Clarke Limited | Construction | 2002 |
| Pacerpole Limited | Manufacturing | 2003 |