| Monetary Research Ltd | Administrative & support | 2025 |
| Motofix (Scotland) Ltd | Wholesale & retail | 2024 |
| Motojoe Holding Limited | Financial services | 2023 |
| Motorrad Central (Scotland) Limited | Wholesale & retail | 2004 |
| MOY Consultancy Ltd | Professional & scientific | 2019 |
| MPP (East & Midlothian) Ltd | Administrative & support | 2025 |
| MR Melts WAX Ltd | Wholesale & retail | 2022 |
| MR T'S Cattery Ltd | Health & social care | 2023 |
| MRB Properties Ltd | Real estate | 2023 |
| MRB Property Investments Ltd | Real estate | 2025 |
| MRS Mindset Ltd | Other services | 2024 |
| MRS Roof Windows Ltd | Construction | 2024 |
| MSM Contracts Scotland Ltd | Construction | 2016 |
| Muir Access Services Limited | Construction | 2025 |
| Mulsanne Motors GT Ltd | Wholesale & retail | 2023 |
| Mungo Park Limited | Real estate | 2008 |
| Murie Mortgage Services Limited | Extraterritorial | 2022 |
| Murphy Brands Ltd | Wholesale & retail | 2024 |
| My Easy Payroll Limited | Professional & scientific | 2022 |
| My Energy AI CIC | Information & communication | 2025 |
| My JL Constructions Ltd | Construction | 2026 |
| My Scottish Ancestors Limited | Other services | 2019 |
| Myers Photography & Design Ltd | Professional & scientific | 2020 |
| Mysa Enterprises Ltd | Health & social care | 2020 |
| N & L Taxis Ltd | Transport & logistics | 1998 |
| Nation Options Limited | Information & communication | 2025 |
| Naturallyemma Limited | Health & social care | 2015 |
| Naveco Superstore Ltd | Wholesale & retail | 2023 |
| NCM Gastroenterology Ltd | Health & social care | 2024 |
| Neat Barbers Ltd | Other services | 2025 |
| Necessary Cat Limited | Arts & recreation | 2023 |
| Neil Williams Haulage Limited | Water & waste | 2012 |
| Neish Holdings Ltd | Professional & scientific | 2025 |
| Netherview Limited | Hospitality | 2003 |
| New Farm Property Limited | Real estate | 2026 |
| New Friendlies Dalkeith Ltd | Hospitality | 2024 |
| New Home Trades Limited | Construction | 2023 |
| New JG Ltd | Hospitality | 2025 |
| New Life Group Ltd | Construction | 2022 |
| Newbattle Golf Club Limited | Arts & recreation | 1934 |
| Newbattle Yoga Company Ltd | Arts & recreation | 2019 |
| Newhaven HB Ltd | Hospitality | 2023 |
| Newton Store 2 Limited | | 2015 |
| Newtongrange Development Trust Ltd | Other services | 2021 |
| Newtongrange Star Football Club Ltd | Arts & recreation | 2023 |
| Newtown Refurb Ltd | Real estate | 2023 |
| Next Mortgage Services Limited | Financial services | 2024 |
| Nicole Harris Ltd | Health & social care | 2011 |
| Niersite Properties Limited | Hospitality | 1983 |
| Ninja Kidz Parks Dundee Ltd | Arts & recreation | 2016 |
| Ninja Kidz Parks Edinburgh Ltd | Arts & recreation | 2014 |
| NMW Design Limited | Professional & scientific | 2024 |
| Nolan Geoscience Services Limited | Professional & scientific | 2022 |
| North ESK Solutions Limited | Information & communication | 2018 |
| Northfield Farm (Dalkeith) Limited | Agriculture & fishing | 2015 |
| Novice Leasing Ltd | Real estate | 2022 |
| Novus Electrical Ltd | Construction | 2025 |
| NSJ Group Limited | Construction | 2019 |
| Numitor Limited | Information & communication | 2018 |
| NW Scotland Ltd | Information & communication | 2011 |
| NWH Construction Services Ltd | Transport & logistics | 2004 |
| NWH Group Limited | Water & waste | 2007 |
| NWH Waste Services (Middleton) Limited | Water & waste | 2014 |
| O & G Telecom Ltd | Professional & scientific | 2011 |
| O'D Safety Services Limited | Professional & scientific | 2019 |
| Ockloo Ltd | Professional & scientific | 2020 |
| ODG Services Ltd | Mining & quarrying | 2025 |
| Old Mill (North ESK) Limited | Construction | 2010 |
| Old Millhouse Dalkeith Ltd | Hospitality | 2014 |
| Old Smoaky Ltd | Wholesale & retail | 2024 |
| Olectrical Ltd | Construction | 2025 |
| One Stop Office Supplies Ltd. | Wholesale & retail | 2004 |
| Only in Edinburgh Limited | Information & communication | 2011 |
| Onpoint Accounting - Franchising Limited | Professional & scientific | 2020 |
| Onpoint Accounting Group Ltd | Professional & scientific | 2020 |
| Onpoint Accounting Limited | Professional & scientific | 2018 |
| Onpoint R&D Limited | Professional & scientific | 2021 |
| Onyx Energy Limited | Professional & scientific | 2023 |
| Open Safety DLG Ltd | Professional & scientific | 2020 |
| Orchard Devlpmt Ltd | Real estate | 2025 |
| Orchard LEA Developments Ltd | Construction | 2023 |
| Origin Property Maintenance Ltd | Construction | 2023 |
| Ormelie Property Limited | Real estate | 2023 |
| Orocco Developments (Scotland) Ltd | Construction | 2021 |
| Osprey Property Maintenance Ltd | Construction | 2022 |
| Otherworld Bar Limited | Hospitality | 2025 |
| Otherworld Brewing Limited | Manufacturing | 2020 |
| Otonx Limited | Information & communication | 2024 |
| OUT of Office Escapes Ltd | Administrative & support | 2023 |
| Overkill Motorcycle Security Ltd | Wholesale & retail | 2024 |
| Oxlings Ltd | Hospitality | 2019 |
| Oyol Consulting Limited | Other services | 2013 |
| Oyol Group Services Ltd | Other services | 2013 |
| Ozone Lothian Ltd | Professional & scientific | 2011 |
| P a Reid Limited | Health & social care | 2017 |
| P D Carpet Fitting Limited | Construction | 2003 |
| P.X. Publishing Ltd. | Information & communication | 2002 |
| Papa Bear Woodworking Ltd | Manufacturing | 2025 |
| Paper Street Publishing Limited | Extraterritorial | 2019 |
| Paul Whyte Access Limited | Professional & scientific | 2005 |