| Livingston Joiners (Ayrshire) Limited | Construction | 2015 |
| Livvy Long Legs Dog Walking & Pet Services Ltd | Other services | 2024 |
| Liyf Bioethanol Ltd | Manufacturing | 2024 |
| Llpm Contracting Limited | Agriculture & fishing | 2025 |
| LM Consultancy Scotland Ltd | Administrative & support | 2019 |
| LM Accountancy Services Ltd | Professional & scientific | 2021 |
| LM Aero Ltd | Manufacturing | 2019 |
| LM Motor Clinic Limited | Wholesale & retail | 2020 |
| LM Motor Company Limited | Wholesale & retail | 2020 |
| LM Motor Group Limited | Financial services | 2024 |
| LN Electrical Glasgow Ltd | Construction | 2021 |
| LN Holdings Ltd | Construction | 2025 |
| Locard Consulting Ltd | Professional & scientific | 2020 |
| Loch Venachar Lodges Limited | Administrative & support | 2023 |
| Lochlea Distilling Company Limited | Manufacturing | 2016 |
| Lochlea Limited | Agriculture & fishing | 2019 |
| Lockdown Recovery and Storage Ltd | Wholesale & retail | 2025 |
| Lockie Williams Limited | Real estate | 2023 |
| Locksoff Ltd | Professional & scientific | 2024 |
| Logie CPQ Consulting Limited | Information & communication | 2026 |
| Loki Transport Scotland Ltd | Transport & logistics | 2018 |
| London Road Tavern Ltd | Hospitality | 2026 |
| Loot Table Collectibles Limited | Wholesale & retail | 2026 |
| Lord's Work Trust Limited | Other services | 2021 |
| Loreny Outdoor & Leisure Limited | Wholesale & retail | 2009 |
| Loreny Vehicle Body Repair Limited | Wholesale & retail | 2015 |
| LOU SMM Limited | Wholesale & retail | 2025 |
| Loudoun Osteopaths Ltd | Health & social care | 2021 |
| Love IS the Key Weddings Limited | Arts & recreation | 2016 |
| Love LOX Glasgow Ltd. | Other services | 2018 |
| Love Outsource Limited | Information & communication | 2021 |
| Loxe Salon Limited | Other services | 2021 |
| LR Flooring Limited | Construction | 2026 |
| Lruk Property Investing Ltd | Real estate | 2025 |
| LSR by Anna Limited | Other services | 2019 |
| Luca Nails and Spa 1523 Ltd | Other services | 2024 |
| Lucas Psychotherapy & Consultancy Ltd | Health & social care | 2024 |
| Luke Kerr Plant & Agri Limited | Construction | 2024 |
| Lukmar Building Services Ltd | Construction | 2019 |
| Lumac Construction Ltd | Construction | 2019 |
| Lumax Homes (Holdings) Limited | Administrative & support | 2006 |
| Lumenology Ltd | Manufacturing | 2023 |
| Lumiescents Ltd | Manufacturing | 2020 |
| Luminary Craft Co Ltd | Manufacturing | 2024 |
| Luna Lime Ltd | Education | 2024 |
| Lunar Therapies Limited | Other services | 2018 |
| Lusk Construction Limited | Construction | 2003 |
| Lusk Ltd | Professional & scientific | 2022 |
| LWB Ltd | Transport & logistics | 2023 |
| Lygate Properties Limited | Real estate | 2020 |
| Lytra Limited | Real estate | 2015 |
| M & F Travel Ltd | Transport & logistics | 2016 |
| M & W Joinery (Ayrshire) Ltd | Construction | 2025 |
| M L Water Ltd | Water & waste | 2024 |
| M Mcewen Flooring Ltd | Construction | 2024 |
| M Mcewen Flooring Specialists Ltd | Construction | 2024 |
| M&A Scot Ltd | Wholesale & retail | 2020 |
| M&Co Services Limited | Professional & scientific | 2020 |
| M-Tec Networks Ltd | Construction | 2026 |
| M. F. Gill Limited | Arts & recreation | 2003 |
| M.E.G Hydro Co Limited | Energy | 2014 |
| M.K.M Consultancy (UK) Ltd | Professional & scientific | 2020 |
| M.K.M Solutions Ltd | Other services | 2024 |
| MA Ayrshire Ltd | Hospitality | 2026 |
| MA Greetings Ltd | Wholesale & retail | 2018 |
| MA Kilmarnock Ltd | Hospitality | 2021 |
| MA Leadership Ltd | Education | 2026 |
| Maak & Sons Ltd | Hospitality | 2025 |
| MAC JNR Ltd | Wholesale & retail | 2024 |
| Macdonald Computer Services Ltd | Other services | 2015 |
| Macdonald Training CIC | Education | 2022 |
| Macdougall Memorials Ltd | Manufacturing | 2017 |
| Macfarlane Heating Services Ltd | Construction | 2025 |
| Macfarlane Medical Ltd | Health & social care | 2018 |
| Mack Direct Ltd | Wholesale & retail | 2026 |
| Mackays Group Trustees Limited | Professional & scientific | 2001 |
| Mackays Stores (Holdings) Limited | Real estate | 1973 |
| Mackays Stores Group Limited | Professional & scientific | 2001 |
| Mackenzie House (Kilmarnock) Limited | Arts & recreation | 2015 |
| Mackenzie Software Limited | Information & communication | 2015 |
| Mackinnon Clean Ltd | Wholesale & retail | 2022 |
| Mackinnon Construction & Developments Ltd | Construction | 2021 |
| Mackintosh & Wylie LLP | | 2010 |
| Maclaren Anderson Property Ltd | Real estate | 2026 |
| Maclaren Anderson Subsea Ltd | Real estate | 2019 |
| Maclay Murray & Spens Tax Services Limited | Administrative & support | 2001 |
| Macleay Motor Engineering Limited | Wholesale & retail | 2001 |
| Macleod Consultancy Ltd | Professional & scientific | 2015 |
| Maconochies of Kilmarnock Limited | Real estate | 1957 |
| Macpherson Lawnturf Limited | Agriculture & fishing | 2001 |
| Macrocom (947) Limited | Wholesale & retail | 1948 |
| MAD Retail Stores Ltd | Wholesale & retail | 2026 |
| Madden Building Consultancy Limited | Professional & scientific | 2023 |
| Maddison Bryce Aesthetics Ltd | Health & social care | 2019 |
| Madras Plus Ltd | Wholesale & retail | 2016 |
| Maggie's Ayrshire PUB Ltd | Hospitality | 2025 |
| Magnum Contracts Ltd | Extraterritorial | 2014 |
| Mahé Made Ltd | Construction | 2026 |
| Malcolm Bell Decorators Ltd | Construction | 2013 |
| Malcolm Steel Limited | Construction | 2007 |