| Mill Valley Cabinet Shop INC | Lee Bennett Goldstein | — | (415) 722 9322 | Other | Fairfax · Marin County | — | — |
| Mill Valley Electric | Paul Lloyd Watson | agustinamingote@gmail.com | (415) 388 3851 | Electricians | Mill Valley · Marin County | — | — |
| Mill Valley Garden Design INC | Jane Van Hook Singer | — | (415) 388 6418 | Windows, patio, painters | Mill Valley · Marin County | — | — |
| Mill Valley Roofing | Mill Valley Roofing | — | (628) 666-6675 | Other roofers | Mill Valley · Marin County | — | — |
| Millar Woodwork & Design | Millar Woodwork & Design | — | (415) 488 0152 | GC, remodel, ADU | Lagunitas · Marin County | — | — |
| Millennial Development INC | Richard Anthony Hynes | — | (415) 847 6301 | GC, remodel, ADU | Novato · Marin County | — | — |
| Millennium Security & Fire | Millennium Security & Fire | — | (415) 342 4013 | Electricians | San Rafael · Marin County | — | — |
| Miller Construction | Joshua Aaron Miller | — | (707) 481 6609 | GC, remodel, ADU | San Rafael · Marin County | — | — |
| Miller Construction | Thomas Fritz Miller | — | (415) 367 5733 | GC, remodel, ADU | Novato · Marin County | — | — |
| Miller Construction | Bradley David Miller | — | (415) 990 4496 | GC, remodel, ADU | Greenbrae · Marin County | — | — |
| Miller Creek Painting Company | Erik Christopher Gaffney | — | (415) 847 4684 | Windows, patio, painters | San Rafael · Marin County | — | — |
| Miller Hicks Building | Jason Miller Hicks | — | (415) 717 8439 | GC, remodel, ADU | Mill Valley · Marin County | — | — |
| Miller Window Covering | Miller Window Covering | — | (415) 328 7517 | Other | Novato · Marin County | — | — |
| Millsap Degnan & Associates INC | Douglas Kevin Degnan | — | (415) 472 4244 | GC, remodel, ADU | San Rafael · Marin County | — | — |
| Millstreet Builders | Craig Alan Fitzpatrick | craigmillstreet@gmail.com | (415) 895 8166 | GC, remodel, ADU | Novato · Marin County | — | — |
| Millwood Construction INC | Juan Carlos Jr Parra | — | (415) 946 9015 | GC, remodel, ADU | San Rafael · Marin County | — | — |
| Millworks Design / Construction | Meredith Stevens Mill | — | (415) 246 4484 | GC, remodel, ADU | Kentfield · Marin County | — | — |
| Milton Woodbury Ghee | Milton Woodbury Ghee | — | (415) 897 7615 | Pool | Novato · Marin County | — | — |
| Mineral Concept INC | Cyril Roland Vanbatten | anapbm@gmail.com | (415) 455 9896 | Other | Sausalito · Marin County | — | — |
| Miracle Mile Management | Miracle Mile Management | jasmin@mimimgmt.com | (415) 456-9622 | Property managers | San Rafael · Marin County | — | — |
| Miranda Construction | Nery Wosvely Miranda Lucas | — | (415) 272 7630 | GC, remodel, ADU | San Rafael · Marin County | — | — |
| Miranda Painting | Miranda Painting | roberto@mirandapainting.com | (415) 849 8813 | Windows, patio, painters | San Rafael · Marin County | — | — |
| Missin Construction | Brendon Michael Missin Woodcock | — | (415) 517 8982 | GC, remodel, ADU | Novato · Marin County | — | — |
| Mitchel Berman Cabinet Makers INC | Mitchel Hue Berman | — | (415) 987 1978 | Other | San Anselmo · Marin County | — | — |
| Mitchell-parra General Contractor | Mitchell-parra General Contractor | — | (415) 300 6264 | Electricians | Novato · Marin County | — | — |
| Mk General Contractor & Management INC | Marcos Raul Crespin | — | (415) 246 5863 | GC, remodel, ADU | Novato · Marin County | — | — |
| Mm Bay Construction | Miletijev Ana | — | (916) 709 1973 | GC, remodel, ADU | Novato · Marin County | — | — |
| Modern Craftsman LLC | Ronald Jordan Suokko | — | (415) 310 6447 | GC, remodel, ADU | Belvedere Tiburon · Marin County | — | — |
| Modern Design Build | Felipe Orona Reyes | — | (415) 747 8633 | GC, remodel, ADU | San Rafael · Marin County | — | — |
| Moises Perez | Moises Perez | moisespgc@gmail.com | (415) 686 6224 | Windows, patio, painters | Novato · Marin County | — | — |
| Moliver Landscape | Moliver Landscape | — | (415) 250 8646 | Windows, patio, painters | San Rafael · Marin County | — | — |
| Monarch Electric | Reece Wilder Clay | customersupport@monarchelectric.com | (609) 900-7679 | Electricians | San Rafael · Marin County | — | — |
| Monarch Gardens | Carolyn Marjorie Mc Dowell-Anderson | info@monarchgardens.com | (415) 453 5544 | Windows, patio, painters | San Rafael · Marin County | — | — |
| Mondot & Co | Michael Frank Mondot | — | (415) 279 5007 | GC, remodel, ADU | Fairfax · Marin County | — | — |
| Monti General Building & Design | Monti General Building & Design | — | (415) 497 4108 | GC, remodel, ADU | Stinson Beach · Marin County | — | — |
| Moore Building | Moore Building | — | (415) 380 8289 | GC, remodel, ADU | Mill Valley · Marin County | — | — |
| Morales 502 Construction INC | Luis Alfonso Morales Calderon | — | (415) 377 3975 | GC, remodel, ADU | San Rafael · Marin County | — | — |
| More Plumbing Company | Michael Philip More | — | (415) 713 1617 | GC, remodel, ADU | San Rafael · Marin County | — | — |
| Morgan Construction | Robert Michalski Morgan | — | (415) 531 5146 | GC, remodel, ADU | San Rafael · Marin County | — | — |
| Morgan Hall | Morgan Hall | morgan.elizabeth.hall@gmail.com | (415) 847 2008 | GC, remodel, ADU | Fairfax · Marin County | — | — |