| League of Stitches Limited | Other services | 2024 |
| Leander Risk Associates Ltd | Administrative & support | 2025 |
| LEE Hill Construction Limited | Construction | 1984 |
| Leeming Livestock Limited | Agriculture & fishing | 2012 |
| Legacy Technologies Limited | Information & communication | 2016 |
| Legal Onions Ltd | Administrative & support | 2024 |
| Leighswood Ltd | Administrative & support | 2022 |
| Levelq Ltd | Real estate | 2017 |
| Levxi Limited | Manufacturing | 2023 |
| Lewis Dalton Copywriting Services Limited | Professional & scientific | 2021 |
| LFB Consulting Limited | Professional & scientific | 2023 |
| LI Europe Ltd | Professional & scientific | 2018 |
| Lightnation Limited | Manufacturing | 2012 |
| Lightwater Farms Limited | Agriculture & fishing | 1976 |
| Lightwater Holdings Limited | Professional & scientific | 1986 |
| Lightwater Leisure Limited | Real estate | 1978 |
| Lightwater Quarries Limited | Mining & quarrying | 1976 |
| Lime Tree Farm Earth & Sky Community Interest Company | Education | 2016 |
| Linsley Brothers (Harrogate) Limited | Real estate | 1962 |
| Lishman Sidwell Campbell & Price Limited | Professional & scientific | 1974 |
| Little Bird Made Ltd | Professional & scientific | 2019 |
| Little Harries Farm and Livery Ltd | Real estate | 2017 |
| Little Nest Soft Play Ltd | Arts & recreation | 2025 |
| Little Newby Park Limited | Construction | 2011 |
| Little Pippins Montessori Nursery Limited | Health & social care | 2019 |
| Little Red BUS Company Limited | Transport & logistics | 2004 |
| Little Seed Field Ltd | Hospitality | 2026 |
| Live Well With Pain CIC | Health & social care | 2014 |
| Living Nostalgia Limited | Wholesale & retail | 2019 |
| LJ Commissioning Services Limited | Professional & scientific | 2010 |
| Lloyd Dales Limited | Construction | 2020 |
| Loan the Look Limited | Wholesale & retail | 2020 |
| Logwise Firewood Ltd | Wholesale & retail | 2022 |
| Loheslehurst | Financial services | 2025 |
| Lotus Linguistics Limited | Professional & scientific | 2016 |
| Louisa Seymour Limited | Professional & scientific | 2025 |
| Louise Shorten Limited | Professional & scientific | 2019 |
| Love Hair (Ripon) Ltd | Other services | 2023 |
| LOW Mill Mews Management Company Limited | Households | 2026 |
| LOW Skellgate RTM Company Limited | Households | 2022 |
| Lowdon Site Engineering Services Limited | Administrative & support | 2007 |
| LTG Hospitality Limited | Hospitality | 2011 |
| Lula's Cafe Ltd | Hospitality | 2022 |
| Luxair Holdings Limited | Financial services | 2013 |
| LW Developments (Yorkshire) Limited | Construction | 2008 |
| LYD IT Services Limited | Information & communication | 2010 |
| Lylley Hall Hotel Ltd | Hospitality | 2018 |
| Lyons Plumbing and Heating Solutions Limited | Construction | 2023 |
| M Canavan Associates Limited | Agriculture & fishing | 2003 |
| M G Air Systems Ltd | Manufacturing | 2006 |
| M People Consulting Ltd | Professional & scientific | 2026 |
| M R Hudson Auto Electrics Limited | Wholesale & retail | 2003 |
| M S Architects Limited | Professional & scientific | 2003 |
| M. Kettlewell (Melmerby) Limited | Transport & logistics | 1973 |
| M. Kettlewell Holdings Limited | Financial services | 2019 |
| M.D.L Construction Solutions Ltd | Construction | 2022 |
| M600 Limited | Information & communication | 2011 |
| MAC CUE Sports and Darts Ltd | Hospitality | 2025 |
| MACH5 Events Ltd | Hospitality | 2024 |
| Macindian Ltd | Manufacturing | 2024 |
| Maddison James Associates Limited | Professional & scientific | 2007 |
| Madeira UK Holdings Limited | Manufacturing | 1983 |
| Madeira UK LLP | | 2017 |
| Madeley Yorkshire Limited | Manufacturing | 2018 |
| Magrs and Co Ltd | Other services | 2025 |
| Maj.Kari Limited | Health & social care | 2016 |
| Mamahope Limited | Manufacturing | 2025 |
| Mamas Matter CIC | Health & social care | 2019 |
| Mamas Move CIC | Health & social care | 2024 |
| Mankrus Ltd | Manufacturing | 2025 |
| Manor Estate Properties (UK) Limited | Real estate | 1997 |
| Manor Farm Ventures Limited | Professional & scientific | 2018 |
| Manorpark Designs Ltd | Administrative & support | 2011 |
| Many Incompetent Layabout Outcasts (Milo) Ltd | Transport & logistics | 2022 |
| Maplebeck Properties Ltd | Households | 2019 |
| MAR Services Direct Ltd | Construction | 2015 |
| March Creative Limited | Professional & scientific | 2022 |
| Marine Tech Appledore Ltd | Manufacturing | 2020 |
| Mark's Auto Services Ltd | Wholesale & retail | 2013 |
| Marleys Butchers Limited | Wholesale & retail | 2010 |
| Martin Mann - IT Ltd | Information & communication | 2025 |
| Masham Family Butchers Ltd | Wholesale & retail | 2025 |
| Masham Farmer's Live Stock Mart Company Limited | Real estate | 1915 |
| Masham Micronized Feeds Limited | Extraterritorial | 1986 |
| Masham Sausages and Burgers Limited | Manufacturing | 2011 |
| Masham Town Hall Community Charity | Arts & recreation | 2010 |
| Masterbuild Services Limited | Information & communication | 2002 |
| Matany Residential Ltd | Real estate | 2025 |
| Matombo Newby Limited | Wholesale & retail | 2015 |
| Matthew Box Electrical Ltd | Construction | 2014 |
| Maunby Investment Management Limited | Financial services | 1982 |
| Maunby Nominees Ltd | Financial services | 1986 |
| Maunby Securities Limited | Financial services | 1986 |
| Maverick Technology Ltd | Manufacturing | 2021 |
| Maxcon Limited | Health & social care | 2025 |
| Mayfield Property Management Company Limited | Households | 2014 |
| MC Property Solutions Ltd | Real estate | 2021 |
| Mccaffery Estates Ltd | Real estate | 2017 |
| Mccaffery Financial Limited | Financial services | 2014 |
| Mcconnell Hollins Limited | Professional & scientific | 2014 |