| Murrieta Pool Company | Chris Andrew Schafer | — | (909) 957 0459 | Electricians | Murrieta · Riverside County | — | — |
| Murrieta Valley Construction | Grant Edward Ghosn | grant@mv-co.com | (951) 376 6638 | GC, remodel, ADU | Murrieta · Riverside County | — | — |
| Murrieta Valley Plumbing INC | Michael Edward Maroney | — | (951) 696 7100 | Other | Murrieta · Riverside County | — | — |
| Murry Electric Incorporated | Remus Tudor Roman | — | (714) 858 4363 | Electricians | Corona · Riverside County | — | — |
| Mustang Plumbing INC | Michael Patrick O'shea | — | (909) 630 2822 | Other | Lake Elsinore · Riverside County | — | — |
| Mv Construction | Michael Jeffrey Vigil | — | (760) 880 0774 | GC, remodel, ADU | Palm Desert · Riverside County | — | — |
| Mv Custom Awnings | Mv Custom Awnings | — | (714) 717 8737 | Other | Perris · Riverside County | — | — |
| Mvg Construction INC | Martin Jr Vargas | — | (951) 532 9297 | GC, remodel, ADU | Jurupa Valley · Riverside County | — | — |
| Mvp Restoration | Juan Antonio Flores | — | (951) 730 3448 | GC, remodel, ADU | Sun City · Riverside County | — | — |
| Mvs Testing | Mvs Testing | — | (442) 402 7101 | Other | Palm Desert · Riverside County | — | — |
| Mw Industrial | Robert Edward Wallace | — | (951) 477 7171 | HVAC | Murrieta · Riverside County | — | — |
| Mwb Construction LLC | Matthew William Bonson | — | (951) 376 3421 | GC, remodel, ADU | Menifee · Riverside County | — | — |
| My Concrete Guy | My Concrete Guy | — | (909) 631 5571 | Other | Corona · Riverside County | — | — |
| My Electrician INC | Brian Montgomery Alston | electriciantenby@gmail.com | (800) 342 6885 | Electricians | Menifee · Riverside County | — | — |
| My General Construction INC | Michael Robert Yakovich | — | (760) 864 7364 | GC, remodel, ADU | Palm Springs · Riverside County | — | — |
| My Home Enterprise INC | Manuel Elias Guerrero | — | (951) 210 2420 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| My Install Guy | Kenneth Bradford Pope | — | (951) 290 9047 | GC, remodel, ADU | Murrieta · Riverside County | — | — |
| My Insulation Guy INC | Jesse Jay Cota | — | (951) 527 7283 | Other | Riverside · Riverside County | — | — |
| My Key Tile & Stone INC | Michael Elmore Alvarez | — | (951) 956 8785 | Other | Anza · Riverside County | — | — |
| My Refrigeration Man INC | Timothy Richard Gilmore | — | (626) 283 2443 | HVAC | Jurupa Valley · Riverside County | — | — |
| Myb Basilio General Engineer | Vicente Jr Bacilio | — | (951) 483 4205 | Other | Perris · Riverside County | — | — |
| Myco Custom Metalworks | Myco Custom Metalworks | — | (951) 473 3768 | HVAC | Temecula · Riverside County | — | — |
| Mycrogrid Incorporated | Vincent Joseph Battaglia | — | (760) 568 3413 | Other roofers | Palm Desert · Riverside County | — | — |
| Myers Marine Division LLC | Stephen Thomas Myers | myersmarinedivision@gmail.com | (951) 817 0525 | GC, remodel, ADU | Norco · Riverside County | — | — |
| Myerson Electric INC | Randy Robert Myers | — | (760) 443 4989 | Electricians | Temecula · Riverside County | — | — |
| Mykon Builders INC | Noah Thomas Rodriguez | — | (909) 446 8300 | GC, remodel, ADU | Calimesa · Riverside County | — | — |
| Mylaine Enterprises DBA Amc Builder | Alex Perez | — | (949) 813 8241 | GC, remodel, ADU | Temecula · Riverside County | — | — |
| Myles Foster Barter | Myles Foster Barter | — | (760) 851 7356 | GC, remodel, ADU | Rancho Mirage · Riverside County | — | — |
| Mynt Construction Services | Christopher John Perry | — | (714) 403 7762 | GC, remodel, ADU | Corona · Riverside County | — | — |
| Myriad Construction Company INC | David Charles Jones | — | (951) 834 2323 | GC, remodel, ADU | Winchester · Riverside County | — | — |
| Mzb Engineering And Construction Incorporated | Humayun Aziz | — | (949) 254 4792 | Other | Corona · Riverside County | — | — |
| N A C Construction | Charles Alexander Ebenhack | — | (951) 545 5693 | GC, remodel, ADU | Norco · Riverside County | — | — |
| N A C Network INC DBA Nelson & Nelson Electrical Contractors | John Patrick Nelson | — | (951) 532 9572 | Electricians | Norco · Riverside County | — | — |
| N B Construction | Bajgyik Norbert | — | (323) 275 7535 | Windows, patio, painters | Wildomar · Riverside County | — | — |
| N B Home Flooring | N B Home Flooring | — | (951) 227 1653 | Other | Riverside · Riverside County | — | — |
| N B I Landscape Development | Travis James Larue | — | (714) 542 1740 | Windows, patio, painters | Corona · Riverside County | — | — |
| N B K Construction | Jorge Raul Martinez | — | (714) 683 8887 | GC, remodel, ADU | Lake Elsinore · Riverside County | — | — |
| N B Painting Corp | Ramon Sandoval | — | (951) 675 6174 | Windows, patio, painters | Jurupa Valley · Riverside County | — | — |
| N C S Contracting | Merabet Ismet | — | (760) 861 1725 | Electricians | La Quinta · Riverside County | — | — |
| N Construction INC | Javier Enrique Navarro-mora | info@nconstruction.com | (760) 848 5802 | GC, remodel, ADU | La Quinta · Riverside County | — | — |