| Keepabeat Training Services Limited | Education | 2018 |
| Kelly & Co Estate Agents Ltd | Real estate | 2013 |
| Kelly & Co Properties Ltd | Real estate | 2013 |
| Kellys Supermarkets Ltd | Wholesale & retail | 2014 |
| Kilmoon Contracts Ltd | Construction | 2025 |
| Kilmoon Developments Limited | Real estate | 2018 |
| Kilmoon Homes Limited | Construction | 2018 |
| Kilmoon Trading Ltd | Construction | 2011 |
| Klubfunder Limited | Administrative & support | 2016 |
| Knockarl Ltd | Real estate | 2021 |
| Knockbann Construction Limited | Construction | 2023 |
| Lagan Property Limited | Real estate | 2013 |
| Lajoa Limited | Extraterritorial | 2016 |
| Leahy Accounting Services Limited | Professional & scientific | 2010 |
| LEC Contracts & Utilities Ltd | Construction | 2021 |
| Life Well NI Ltd | Health & social care | 2016 |
| Ligid Productions Ltd | Information & communication | 2010 |
| Link Electrics Limited | Manufacturing | 2021 |
| Linty Group Ltd | Construction | 2026 |
| Lismoyle Construction Limited | Construction | 2010 |
| Logsplit Limited | Wholesale & retail | 2018 |
| Lucky Dragon Maghera Limited | Hospitality | 2023 |
| M & M Bradley Ltd | Wholesale & retail | 2006 |
| MA Motorcycles Ltd | Wholesale & retail | 2021 |
| MAC Construction Services Ltd. | Administrative & support | 2017 |
| Macknagh Assets Ltd | Real estate | 2024 |
| Maghera Construction Limited | Construction | 2024 |
| Maghera Dental Ltd | Health & social care | 2018 |
| Maghera Development Association Limited | Other services | 1994 |
| Maghera Parish Caring Association | Health & social care | 2012 |
| Maghera Pizza Co Ltd | Hospitality | 2024 |
| Mallon & Co Solicitors Limited | Professional & scientific | 2014 |
| Mame Holdings Ltd | Real estate | 2025 |
| Mceldowney Enterprise Limited | Administrative & support | 2020 |
| Mcgahon Contracts Ltd | Construction | 2017 |
| Mcgonigle Engineering Ltd | Professional & scientific | 2026 |
| Mcgrath Pattison Ltd | Professional & scientific | 2011 |
| Mcguigan Bros Contracts Ltd | Construction | 2021 |
| Mcguigan Energy Ltd | Energy | 2022 |
| Mcguinness Opticians Limited | Health & social care | 2014 |
| Mckeefrys of Maghera Limited | Wholesale & retail | 2000 |
| Mckees Foods Ltd | Manufacturing | 2020 |
| Mckennas' Bar (1908) Ltd | Hospitality | 2011 |
| Mcnicholl Holdings Limited | Real estate | 2019 |
| Mcwilliams Farms Ltd | Agriculture & fishing | 2020 |
| Mcwilliams Group Limited | Financial services | 2019 |
| Meenablagh Ltd | Energy | 2010 |
| Meenan Square Limited | Real estate | 2010 |
| Mel's Chippy Limited | Hospitality | 2018 |
| Melanie S Fishing Limited | Agriculture & fishing | 2009 |
| MFL Plant Machinery Ltd | Manufacturing | 2016 |
| Mg&S Construction Ltd | Construction | 2017 |
| Mgward Limited | Information & communication | 2017 |
| MHS Heritage & Culture Ltd | Education | 2018 |
| MID Ulster Accounting Ltd | Professional & scientific | 2025 |
| MID Ulster Construction Ltd | Construction | 2021 |
| MID Ulster Tyre Centre Limited | Wholesale & retail | 2025 |
| Mid-Ulster Homes Limited | Real estate | 2003 |
| Mill Bank Park Management Company Limited | Real estate | 2025 |
| Millriver Investments Ltd | Construction | 2015 |
| MJQ Electrical Ltd | Construction | 2007 |
| MKM Plastering Contracting Ltd | Construction | 2016 |
| MOD Electrics Ltd | Construction | 2026 |
| MOL Tools & Abrasives Limited | Administrative & support | 2002 |
| Mountain View Lodges and Spa Ltd | Hospitality | 2019 |
| Moyola Farm Ltd | Agriculture & fishing | 2014 |
| Moyola Installation Ltd | Construction | 2024 |
| MR Monochrome Ltd | Arts & recreation | 2021 |
| Mrgn Mechanical Limited | Construction | 2022 |
| MTS (Tank Cleaning) Limited | Administrative & support | 1992 |
| Nelson Construction (N.I.) Ltd | Construction | 2016 |
| Nesbitt Plumbing & Heating Limited | Construction | 2022 |
| Nest Group Counselling (Ireland) Limited | Health & social care | 2003 |
| Nguyen Hieu Ltd | Wholesale & retail | 2024 |
| NKP Songs Ltd | Information & communication | 2026 |
| Noones of Maghera Limited | Wholesale & retail | 2014 |
| North West Ground Care Limited | Administrative & support | 2025 |
| Northern Counties Development Association | Arts & recreation | 1999 |
| Northern Ireland Aquaculture Representative Group | Agriculture & fishing | 2023 |
| Nourishing Those WE Love Limited | Professional & scientific | 2022 |
| OKC Limited | Construction | 2013 |
| Orto Bedford Street Ltd | Hospitality | 2023 |
| Orto Pizza Holdings Limited | Financial services | 2022 |
| Oshra Ltd | Real estate | 2016 |
| Overhead Network Solutions Ltd | Construction | 2019 |
| P & S Fresh Ltd | Hospitality | 2017 |
| P&K Mckaigue Limited | Construction | 2002 |
| P.S.F. Energy Limited | Real estate | 2024 |
| Pagoda 998 Limited | Hospitality | 2024 |
| PAT Cassidy Groundwork Services Ltd | Construction | 2015 |
| Patrick Bradley Architect Ltd | Professional & scientific | 2014 |
| PIO Specialist Autos Ltd | Wholesale & retail | 2025 |
| Pjdon Investments Ltd | Financial services | 2022 |
| PMC Health & Safety Services Ltd | Construction | 2015 |
| PMC Training Services Ltd | Construction | 2015 |
| PMK Concrete Flooring Limited | Construction | 2022 |
| Powertech (N.I.) Limited | Energy | 2015 |
| Prestige Homes (2011) Ltd | Construction | 2011 |
| Prionta Ltd | Manufacturing | 2021 |
| Pro Events and Utility Hire Ltd | Administrative & support | 2026 |