| Marchese Contracting Services | Jason Elijah Marchese | — | (805) 801 7271 | GC, remodel, ADU | Pismo Beach · San Luis Obispo County | — | — |
| Marcus Stephens Const | Marcus Stephens Const | — | (805) 710 1705 | GC, remodel, ADU | Grover Beach · San Luis Obispo County | — | — |
| Mari Landscaping INC | Margaret Ann Battaglia | info@marilandscaping.com | (805) 226 9787 | Windows, patio, painters | Paso Robles · San Luis Obispo County | — | — |
| Marin Pacific Electric | Marin Fragosa Gonzalez | — | (949) 433 5755 | Electricians | Atascadero · San Luis Obispo County | — | — |
| Mario M Landeros Electric Service | Mario Mora Landeros | — | (805) 268 9091 | Electricians | Nipomo · San Luis Obispo County | — | — |
| Mark A Swan | Mark A Swan | — | (408) 210 2149 | Windows, patio, painters | Atascadero · San Luis Obispo County | — | — |
| Mark Alonzo Construction LLC | Mark Felix Alonzo | — | (805) 801 2616 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Mark E Brunschwiler Contractor | Mark E Brunschwiler Contractor | — | (805) 909 9483 | GC, remodel, ADU | Cambria · San Luis Obispo County | — | — |
| Mark Ginder Construction | Mark Lyle Ginder | — | (805) 550 4867 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Mark Greenaway Construction | Mark David Greenaway | — | (805) 466 7076 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Mark Mitchell Crisp | Mark Mitchell Crisp | — | (800) 359 2747 | Other | Nipomo · San Luis Obispo County | — | — |
| Mark Pinney Painting | Mark Pinney Painting | — | (805) 927 0690 | Windows, patio, painters | Paso Robles · San Luis Obispo County | — | — |
| Mark Scobie Construction | James Mark Scobie | — | (805) 610 6805 | Other | Paso Robles · San Luis Obispo County | — | — |
| Mark Stones Floor Covering | Mark Stones Floor Covering | — | (661) 246 6778 | Other | Morro Bay · San Luis Obispo County | — | — |
| Mark Sullivan Fine Custom Homes INC | Mark Truman Sullivan | — | (805) 710 6200 | GC, remodel, ADU | Pismo Beach · San Luis Obispo County | — | — |
| Mark Switzer Excavating | Mark Irvin Switzer | — | (805) 237 1334 | Other | Paso Robles · San Luis Obispo County | — | — |
| Mark T Nelson Construction | Mark T Nelson | — | (805) 441 3146 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Mark Wallace Plumbing | Mark Wallace Plumbing | — | (559) 359 7348 | Other | Los Osos · San Luis Obispo County | — | — |
| Mark Worrell Construction | Mark Anthony Worrell | — | (805) 619 5138 | GC, remodel, ADU | Arroyo Grande · San Luis Obispo County | — | — |
| Marks Construction Service | Mark Raymond Stoneburner | — | (805) 550 4418 | Other | Nipomo · San Luis Obispo County | — | — |
| Markus Link DBA Link Electrix | Markus Link DBA Link Electrix | — | (714) 566 4317 | Electricians | Paso Robles · San Luis Obispo County | — | — |
| Marquart Plumbing And Contracting | Benjamin Stephen Marquart | — | (805) 423 9338 | Other | Templeton · San Luis Obispo County | — | — |
| Marquina's Landscape | Marquina's Landscape | — | (805) 458 0496 | Windows, patio, painters | Los Osos · San Luis Obispo County | — | — |
| Marseilles Plumbing LLC | William Edwin Marseilles | — | (805) 466 6890 | Other | Atascadero · San Luis Obispo County | — | — |
| Martin Michel General Contractor | Martin Michel General Contractor | — | (805) 286 7597 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Martinez Granite Counter Tops | Martinez Granite Counter Tops | — | (805) 930 7063 | Other | Atascadero · San Luis Obispo County | — | — |
| Marval Landscaping Service | Martin Valdez-Aviles | — | (805) 602 2230 | Windows, patio, painters | Grover Beach · San Luis Obispo County | — | — |
| Marwal Construction INC | Marcia Lynn Walther | — | (805) 441 7548 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Mary E Mc Clure General Building Contractor | Mary Ellen Mc Clure | — | (559) 280 6335 | GC, remodel, ADU | Grover Beach · San Luis Obispo County | — | — |
| Marzo Tile | Marzo Tile | — | (818) 209 9828 | Other | Shell Beach · San Luis Obispo County | — | — |
| Masen's Custom Tile Works | Masen's Custom Tile Works | — | (805) 835 8266 | Other | Templeton · San Luis Obispo County | — | — |
| Master Craft Wood Products | Master Craft Wood Products | — | (805) 995 2078 | Other | Cayucos · San Luis Obispo County | — | — |
| Master Finish Painting | Master Finish Painting | — | (805) 400 9878 | Windows, patio, painters | San Miguel · San Luis Obispo County | — | — |
| Matejcek Landscaping | Matejcek Landscaping | — | (805) 679 8377 | Windows, patio, painters | Atascadero · San Luis Obispo County | — | — |
| Mathers Tile & Stone INC | Michael Phillip Mathers | — | (805) 458 9079 | Other | San Miguel · San Luis Obispo County | — | — |
| Matrix General Engineering Contractor | Matrix General Engineering Contractor | — | (805) 331 5815 | Windows, patio, painters | Templeton · San Luis Obispo County | — | — |
| Matt Clark Tile INC | Matthias William Clark | mctile@gmail.com | (805) 215 4433 | Other | Los Osos · San Luis Obispo County | — | — |
| Matt List Construction | Matthew Richard List | — | (805) 704 6872 | GC, remodel, ADU | Nipomo · San Luis Obispo County | — | — |
| Matt Newman Construction | Matthew Edward Newman | — | (805) 459 5605 | Other | Los Osos · San Luis Obispo County | — | — |
| Matthew Cathey | Matthew Cathey | — | (805) 704 3781 | Windows, patio, painters | Atascadero · San Luis Obispo County | — | — |