M
| M-Lane | AOR/Pop Rock | Русе | 2015 |
| M-otive | Alternative Rock | София | 2013 |
| M.I.R.F. | Black/Death Metal | София | 2010 |
| M.M.M. | Progressive Metal | Враца | 1994 |
| M.R.A.K. | Alternative Rock/Stoner Rock | Варна | 2012 |
| Macrophone | Indie Rock | София | 2004 |
| Made Of Less | Alternative/Grunge | София | 2013 |
| Madhouse Room | Alternative Rock | Пловдив | 2018 |
| Magnetic | Crossover | София | 2012 |
| Malformation | Black Metal | Дупница | 1992 |
| Maltworm | Death Metal | София | 2018 |
| Maniacal Pictures | Punk Rock/Alternative Rock | Варна | 1990 |
| Many More | Heavy Metal | София | 2017 |
| Marauders Inc. | Stoner Rock/Alternative Rock | София | 2013 |
| Mary Boys Band | Pop Rock | София | 1994 |
| Mass Confusion | Thrash Metal | Враца | 2010 |
| Mass Cremation | Thrash Metal/Old School Death Metal | Варна | 2012 |
| Mass Grave | Death Metal/Grindcore | Кюстендил | 2005 |
| Matchpoint | Indie Rock | София | 2006 |
| Matubes | Black Metal | Свищов | 2015 |
| Maze | Alternative Metal | София | 2008 |
| Maze Hunters | Indie Rock | София | 2018 |
| Me And My Devil | Psychedelic Rock/Аlternative | София | 2020 |
| Mean Men | Glam Rock | София | 1992 |
| Meanstream | Hardcore | Варна | 1994 |
| Melancholic Journey | Black Metal | Лом/София | 2011 |
| Melekh | Hardcore/Metalcore | София | 2004 |
| Melissa | Thrash/Speed Metal | Шумен | 1988 |
| Memory Affliction | Doom/Death Metal | София | 2020 |
| Menstrual Cocktail | Goregrind | София | 2009 |
| Mental Architects | Math Rock/Progressive Rock | София | 2001 |
| Mental Destruction | Thrash Metal | Пловдив | 2008 |
| Mental Reborn | Melodic Death Metal | Велико Търново | 2008 |
| Mephistoo | Dark Wave | Радомир | 1990 |
| Merian | Hard Rock | Пловдив | 2013 |
| Meridian Run | Beatdown/Hardcore | Варна/София | 2012 |
| Metal Heart | Alternative Rock | Петрич | 2009 |
| Metal Hit | Heavy Metal | Ямбол | 1991 |
| Metalbolizm | Progressive Metal | София | 2006 |
| Metalwings | Symphonic Gothic Metal | София | 2010 |
| MID | Punk Rock | Враца | 2002 |
| Milenium X | Pop Rock | София | 2015 |
| Militia | Thrash Metal/Alternative/Grunge | Търговище | 2015 |
| Millennium | Progressive Rock | София | 1987 |
| Minaton | Hard Rock/AOR | Бернбург (Германия) | 1990 |
| Mind Disorder | Alternative Rock | София | 2009 |
| Mindflux | Alternative Rock | Пловдив | 2016 |
| Mindfold Express | Progressive Metal/Djent | Русе | 2009 |
| Mindown | Alternative Rock | Асеновград | 1999 |
| Mirror | Alternative Rock | Провадия | 2014 |
| Miry | Indie Rock | Хъдърсвилд (Англия)/София | 2010 |
| Miss Mona | Hard Rock/Glam Rock | Стара Загора/Пловдив | 1993 |
| Missing The Point | Hardcore | Асеновград | 2005 |
| Mister | Heavy Metal | Варна | 1991 |
| Mister Hard | Progressive Rock/AOR | Варна | 1994 |
| Misty | Punk | Враца | 1994 |
| Mitko Trend | Alternative Rock | Бургас | 2015 |
| Mixed Up | Hard Rock/Alternative Metal | Пловдив | 2015 |
| Mizerere | Death Metal/Grindcore | София | 2006 |
| Mneme | Death Metal | София | 2011 |
| Modica | Alternative Rock | Панагюрище | 2013 |
| MoGa | Experimental Death Metal | София | 2022 |
| Mono | Pop Rock | София | 2016 |
| Moon Orchard | Post-Black Metal/Ambient | Розенхайм (Германия) | 2012 |
| Moonparticle | Progressive Rock | Лондон (Англия) | 2017 |
| Moor | Black Metal | Нови пазар | 2015 |
| Morbid | Progressive Metal | София | 2019 |
| Moria | Black Metal | София | 2002 |
| Morion | Gothic Metal | София | 2003 |
| morrum | Progressive Metal/Rock | София | 2009 |
| Mortal Illumination | Black Metal | София/Разлог | 2013 |
| Mortal Remains | Doom/Death Metal | Плевен | 1991 |
| Mortem Animalium | Black Metal | София | 2004 |
| Morth | Melodic Black Metal | Сандански | 2002 |
| Mortuary | Thrash/Death Metal | Враца | 1990 |
| Mosh-Pit Justice | Power Thrash Metal | Бургас | 2012 |
| Mother Elephant | Stoner/Doom Metal | София | 2022 |
| Mother His Mother | Metalcore/Deathcore | Русе/Шумен | 2019 |
| Mother Tribe | Hard Rock | София | 2017 |
| Mr.Pertrubat | Heavy Metal | София | 2018 |
| Mr.Phantom | Power Metal | София | 2008 |
| Muddy | Sludge Metal/Psychedelic Experimental | София | 2013 |
| Murder Of Crows | Doom/Death Metal | София | 2010 |
| Music Station | Progressive Rock | София | 2002 |
| Musicoholic | Alternative/Psychedelic Rock | София | 2014 |
| My Disorder | Alternative Rock | София | 2011 |
| My Own Destiny | Metalcore | Варна | 2013 |
| Mystica | Progressive Metal | София | 2003 |