| MADISON RECRUITMENT LIMITED | Registered | NZ Limited Company | 619788 | government contract suppliers |
| MADSEN & GREEN CONTRACTING LIMITED | In Liquidation | NZ Limited Company | 2130595 | government contract suppliers |
| MADSEN CONTRACTORS LIMITED | Registered | NZ Limited Company | 9365343 | government contract suppliers |
| MAEVA GRZES & ASSOCIATES - PSYCHOLOGICAL SERVICES LIMITED | Registered | NZ Limited Company | 8265490 | government contract suppliers |
| MAFIC PARTNERS LIMITED | Registered | NZ Limited Company | 7552996 | government contract suppliers |
| Maggie Barry Trust | Unknown | - | - | mp interest |
| MAGGIE UNLIMITED LIMITED | Removed | NZ Limited Company | 874908 | |
| Magic Moments Foundation | Registered | Charitable Trust | - | corporate donations |
| MAGNETISM SOLUTIONS LIMITED | Registered | NZ Limited Company | 2199955 | government contract suppliers |
| MAGPIE INVESTMENTS LIMITED | Registered | - | - | |
| Magpie Nest Café | Unknown | - | - | corporate donations |
| MAGUIRE AND HARFORD ARCHITECTS LIMITED | Registered | NZ Limited Company | 4037838 | government contract suppliers |
| MAHAANUI KURATAIAO LIMITED | Registered | NZ Limited Company | 1965566 | government contract suppliers |
| MAHANA BERRIES LIMITED | Registered | - | - | |
| Mahara Gallery | Registered | Charitable Trust | - | councillor interest |
| Mahara Gallery Trust | Unknown | - | - | councillor interest |
| MAHARA OKEROA & ASSOCIATES LIMITED | Registered | NZ Limited Company | 2236246 | |
| Mahé Drysdale Promotions Limited | Registered | NZ Limited Company | - | councillor interest |
| MAHI TAHI MEDIA LIMITED | Registered | NZ Limited Company | 6400693 | government contract suppliers |
| Māhia Beach Resort | Unknown | - | - | iwi subsidiaries |
| Mahitahi Trust | Unknown | - | - | government contract suppliers |
| MAHORA PHARMACY LIMITED | Registered | NZ Limited Company | 161279 | government contract suppliers |
| Mahuika House Trust | Registered | Charitable Trust | - | councillor interest |
| Mahurangi College Board of Trust | Unknown | - | - | mp interest |
| Mahurangi College Board of Trustees | Unknown | - | - | mp interest |
| MĀHURU TRUST LIMITED | Registered | NZ Limited Company | 8769267 | iwi subsidiaries |
| Mahuta Whanau Trust | Unknown | - | - | mp interest |
| Mahuta Whānau Trust | Unknown | - | - | mp interest |
| MAI Experience | Unknown | - | - | government contract suppliers |
| Mai Lighthouse Trust | Unknown | - | - | government contract suppliers |
| MĀIA CENTRE FOR SOCIAL JUSTICE AND EDUCATION LIMITED | Registered | NZ Limited Company | 8130968 | government contract suppliers |
| MĀIA COLLECTIVE LIMITED | Removed | NZ Limited Company | 9283025 | corporate donations |
| MAIN ROAD PARTNERS (2024) LIMITED | Registered | NZ Limited Company | 9277936 | government contract suppliers |
| MAINFREIGHT LIMITED | Registered | NZ Limited Company | 102720 | mp interest |
| MAINLAND INTERIORS LIMITED | Registered | NZ Limited Company | 5705391 | government contract suppliers |
| MAINLAND PIPELINE INSPECTIONS LIMITED | Registered | NZ Limited Company | 808389 | government contract suppliers |
| MAINLAND SURVEYING LIMITED | Registered | NZ Limited Company | 4489398 | government contract suppliers |
| MAINLAND VECTOR CONTRACTING LIMITED | Registered | NZ Limited Company | 2264567 | government contract suppliers |
| MAINLINE CONSTRUCTION LIMITED | Registered | NZ Limited Company | 2216680 | government contract suppliers |
| MAINLINE CONTRACTING LIMITED | Removed | NZ Limited Company | 1143411 | government contract suppliers |
| MAINLY FAUNA LIMITED | Registered | NZ Limited Company | 5425323 | government contract suppliers |
| MAINLY NATIVES PLANT NURSERY LIMITED | Registered | NZ Limited Company | 1572323 | government contract suppliers |
| MAINPOWER NEW ZEALAND LIMITED | Registered | NZ Limited Company | 568270 | councillor interest |
| MainPower NZ Trust | Unknown | - | - | councillor interest |
| MAINPOWER TRUST INVESTMENTS LIMITED | Registered | NZ Limited Company | 1208704 | councillor interest |
| MAIRE BELL STEPHENSON TRUSTEE LIMITED | Registered | NZ Limited Company | 8148885 | councillor interest |
| MAJB LIMITED | Removed | NZ Limited Company | 1113810 | |
| Major furnace Australia | Unknown | - | - | government contract suppliers |
| Majulie Trust | Registered | Trust | - | councillor interest |
| Mākara Community Centre Association | Registered | Incorporated Society | - | councillor interest |
