| Matthew Golding DBA Golding Concrete Sawing | Golding Concrete Sawing | — | (805) 391 0114 | Other | Santa Margarita · San Luis Obispo County | — | — |
| Matthew Scotti Electic | Matthew Scotti Electic | — | (805) 400 8881 | Electricians | Paso Robles · San Luis Obispo County | — | — |
| Maul Construction | Martin Loren Maul | — | (707) 884 1842 | GC, remodel, ADU | Morro Bay · San Luis Obispo County | — | — |
| Maul Plumbing | Maul Plumbing | allplumbing.steve@gmail.com | (805) 610-2598 | Other | Atascadero · San Luis Obispo County | — | — |
| Maximum Services Company | Tom Byron Christensen | — | (805) 358 8605 | HVAC | Los Osos · San Luis Obispo County | — | — |
| May Construction | Thomas Alan May | — | (805) 235 6523 | GC, remodel, ADU | Los Osos · San Luis Obispo County | — | — |
| Mayer Construction | James Bradley Mayer | — | (805) 772 3023 | GC, remodel, ADU | Morro Bay · San Luis Obispo County | — | — |
| Mazzi Well Drilling | Mazzi Well Drilling | — | (805) 610 2509 | Other | Templeton · San Luis Obispo County | — | — |
| Mb Electrical Services | Mark Allen Bundren | — | (805) 400 9260 | Electricians | Templeton · San Luis Obispo County | — | — |
| Mbg Construction | Matthew Bohannon Giles | matt@mbg-construction.com | (805) 695 9662 | GC, remodel, ADU | Morro Bay · San Luis Obispo County | — | — |
| Mc Cann Plumbing | Mc Cann Plumbing | — | (805) 466 5593 | Other | Atascadero · San Luis Obispo County | — | — |
| Mc Closkey Heating Air Cond & Refrigeration | Allen Ray Mc Closkey | — | (805) 441 0997 | HVAC | Paso Robles · San Luis Obispo County | — | — |
| Mc Connell Construction | Stephen Anthony Mc Connell | — | (805) 441 6856 | GC, remodel, ADU | Morro Bay · San Luis Obispo County | — | — |
| Mc Cune Design | Mc Cune Design | — | (805) 550 0631 | Other | Arroyo Grande · San Luis Obispo County | — | — |
| Mc Fadden Electric | Russell Stuart Mc Fadden | — | (817) 713-0359 | Electricians | San Miguel · San Luis Obispo County | — | — |
| Mc Ginty Construction | Patrick Donald Mc Ginty | — | (805) 441 8383 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Mc Lean Roofing INC | Connie Jean Mclean | — | (805) 473 8692 | Other roofers | Nipomo · San Luis Obispo County | — | — |
| Mc Namara Realty | Mc Namara Realty | — | (805) 543-7777 | Property managers | San Luis Obispo · San Luis Obispo County | — | — |
| Mc Nary Construction | James Arthur Mc Nary | — | (805) 473 0155 | GC, remodel, ADU | Arroyo Grande · San Luis Obispo County | — | — |
| Mccaffrey Painting | Mccaffrey Painting | — | (805) 538 4111 | Windows, patio, painters | Templeton · San Luis Obispo County | — | — |
| Mcclure | Michael Joseph Mcclure | — | (805) 440 5593 | GC, remodel, ADU | Morro Bay · San Luis Obispo County | — | — |
| Mcem Construction | Jaime Barajas | — | (805) 260 3518 | GC, remodel, ADU | Nipomo · San Luis Obispo County | — | — |
| Mckenzie Productions | Wade Hiram Mckenzie | mckenzieproinc@gmail.com | (805) 460 6648 | GC, remodel, ADU | Templeton · San Luis Obispo County | — | — |
| Mecham Drywall | Mecham Drywall | — | (805) 674 5106 | Other | Paso Robles · San Luis Obispo County | — | — |
| Meehan Electric | Danny Charles Meehan | — | (805) 218 2415 | Electricians | Paso Robles · San Luis Obispo County | — | — |
| Megna Construction | John Robert Jr Megna | — | (805) 714 8330 | Electricians | Nipomo · San Luis Obispo County | — | — |
| Meissner Construction | Mark Edward Meissner | — | (805) 235 5439 | Electricians | Atascadero · San Luis Obispo County | — | — |
| Mejia Concrete | Mejia Concrete | julian@mejiaconcrete.com | (805) 709 8137 | Other | Nipomo · San Luis Obispo County | — | — |
| Mel Hooper Construction | Melvin Wade Hooper | — | (805) 550 3130 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Mel's Lock & Key Service | Brad Leroy Williamson | — | (805) 927 4250 | Other | Cambria · San Luis Obispo County | — | — |
| Melius Services | Robert Herculano Rea | — | (805) 748 9338 | GC, remodel, ADU | Pismo Beach · San Luis Obispo County | — | — |
| Mello & Sons Pumps & Motors | Wesley Alfred Mello | — | (805) 481 1286 | Other | Arroyo Grande · San Luis Obispo County | — | — |
| Mello Flooring | Mello Flooring | — | (831) 713 6227 | Other | Paso Robles · San Luis Obispo County | — | — |
| Mendez Roofing | Mendez Hernandez Raul | — | (805) 400 9740 | Other roofers | Atascadero · San Luis Obispo County | — | — |
| Mercado Gardening And Hauling INC | Bibiano Luis Mercado Cabrera | — | (805) 927 1314 | Windows, patio, painters | Cambria · San Luis Obispo County | — | — |
| Mercado Landscape | Mercado Landscape | — | (805) 423 4648 | Windows, patio, painters | Paso Robles · San Luis Obispo County | — | — |
| Merit Heating And Air | Merit Heating And Air | — | (805) 550 5654 | HVAC | Pismo Beach · San Luis Obispo County | — | — |
| Merondy INC | Ronald Louis Blaski | — | (805) 462 8133 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Mesa Air Heating / Air Conditioning INC | Stephen James Mongillo | — | (805) 489 5354 | HVAC | Nipomo · San Luis Obispo County | — | — |
| Mfi Limited | Laurie Ann Mangano | — | (805) 704 9364 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |