| Main Care Pharmacy and Clinic, Milton, Services pharmaceutiques | Milton |
| Main Care Pharmacy and Clinic, Milton, Clinique sans rendez-vous | Milton |
| Main Street Pharmacy, Services pharmaceutiques | Milton |
| Maple Medical Pharmacy, Services pharmaceutiques | Milton |
| March of Dimes Canada, West Central Regional Office, Programme de logement avec soutien, Oakville - Jean and Howard Caine Apartments - Services des soins auxiliaires | Oakville |
| Marche des dix sous Canada, Marche des dix sous Canada, Siège social | Toronto |
| Marche des dix sous du Canada (La), Programme d'adaptation des habitations et des véhicules | London |
| Marketplace Medical Centre, Clinique médicale sans rendez-vous avec un cabinet de médecine générale | Milton |
| Marketplace Pharmacy | Milton |
| MaxCare Medical Centre | Oakville |
| Medcare Pharmacy, Services Pharmaceutiques | Oakville |
| Medicare Pharmacy, Services Pharmaceutiques | Oakville |
| Medicine Shoppe (The), Milton - 400 rue Main Est, Services de pharmacie | Milton |
| Medicine Shoppe (The), Oakville, Services de pharmacie | Oakville |
| MedSleep, Respirologie and médecine du sommeil | Milton |
| Métis Nation of Ontario, Direction de la guérison et du mieux-être - Programmes des services aux victimes | Ottawa |
| Métis Nation of Ontario, Métis Nation of Ontario, Ottawa - rue Slater | Ottawa |
| Metro Pharmacy, Georgetown, Services pharmaceutiques | Halton Hills |
| Metro Pharmacy, Milton, Services pharmaceutiques | Milton |
| Metro Pharmacy, Oakville - Chemin North Service Ouest, Services pharmaceutiques | Oakville |
| Metro Pharmacy, Oakville - Chemin Upper Middle Est, Services pharmaceutiques | Oakville |
| Metrolinx | Toronto |
| Milton Family Care Centre, Cabinet de médecine générale et clinique sans rendez-vous | Milton |
| Milton Health Centre, Clinique sans rendez-vous | Milton |
| Milton Life Care Pharmacy, Services pharmaceutiques | Milton |
| Milton Meals on Wheels | Milton |
| Milton Square Pharmacy, Services Pharmaceutiques | Milton |
| Milton Trails Medical Clinic and Walk-In | Milton |
| Milton Urgent Care Clinic | Milton |
| Miltowne Pharmacy | Milton |
| Mindforward Brain Injury Services | Mississauga |
| Mindforward Brain Injury Services, Assisted Living | Oakville |
| Mindforward Brain Injury Services, Programme de jour pour adultes | Oakville |
| Mint Care Medical Centre and Walk In Clinic | Oakville |
| Mint Care Pharmacy, Services Pharmaceutiques | Oakville |
| Mission Ceridian | Winnipeg |
| Mississauga Halton Central West Regional Cancer Program, Trillium Health Partners - Credit Valley Hospital - Carlo Fidani Regional Cancer Centre, Diagnostic Assessment Program (DAP) | Mississauga |
| Mississauga Halton Centre for Complex Diabetes Care, Soins complexes pour le diabète | Oakville |
| Mississauga Woman's Clinic | Cooksville |
| Mood Disorders Association of Ontario | Toronto |
| Morelli's, Services Pharmaceutiques | Oakville |
| Morelli's, Oakville - Chemin Cornwall, Services Pharmaceutiques | Oakville |
| Morelli's, Oakville - Rue Dundas Est, Services Pharmaceutiques | Oakville |
| Morgentaler Clinic (The) | Toronto Centre-ville Nord |
| Moulin Microcrédits, Bureau de Toronto | Toronto |
| Multiple Births Canada, Naissances multiples Canada | Richmond Hill |
| Muslim Community Services, Muslim Community Services, Mississauga | Mississauga |
