| R & J Construction INC | Ronald Glen Longchamps | — | (925) 648 7942 | HVAC | Danville · Contra Costa County | — | — |
| R & K Bonner INC | Kathy Diane Bonner | info@rkbonnerinc.com | (925) 360 0611 | GC, remodel, ADU | Pleasant Hill · Contra Costa County | — | — |
| R & M Painting | R & M Painting | — | (925) 595 4442 | Windows, patio, painters | Martinez · Contra Costa County | — | — |
| R & M Roofing Solutions | Erick Steven Reyes Coto | — | (707) 641 6198 | Other roofers | Antioch · Contra Costa County | — | — |
| R & P Garage Doors | R & P Garage Doors | — | (925) 516 4235 | Other | Discovery Bay · Contra Costa County | — | — |
| R & R Landscaping INC | Rodriguez Ricardo | — | (909) 728 9235 | Windows, patio, painters | Pittsburg · Contra Costa County | — | — |
| R & R Roofing | Robertina Diaz | — | (925) 481 9392 | Other roofers | Oakley · Contra Costa County | — | — |
| R & R Roofing | Ruben Alexander Fuentes | — | (925) 421 8913 | Other roofers | Concord · Contra Costa County | — | — |
| R & S Erection Of Concord INC | Mario Ernesto Avalos | — | (925) 671 7606 | Other | Concord · Contra Costa County | — | — |
| R & S Erection Of Richmond INC | Shawn Roland Trask | — | (510) 232 2062 | Other | Richmond · Contra Costa County | — | — |
| R & T Pro Remodeling | Torrez Edmundo Rodrigues | — | (510) 672 6899 | GC, remodel, ADU | Richmond · Contra Costa County | — | — |
| R A Concrete Solution | R A Concrete Solution | — | (415) 571 7656 | Other | Antioch · Contra Costa County | — | — |
| R A D Sierra Builders INC | Ahmet Kahya | — | (510) 379 6214 | GC, remodel, ADU | Rodeo · Contra Costa County | — | — |
| R A M General Contractor | R A M General Contractor | richardamaestas@gmail.com | (510) 697 8703 | GC, remodel, ADU | Martinez · Contra Costa County | — | — |
| R A M Industries | R A M Industries | — | (925) 634 3186 | GC, remodel, ADU | Brentwood · Contra Costa County | — | — |
| R A Plastering INC | Randy Jeremy Reed | — | (510) 205 5241 | Other | Martinez · Contra Costa County | — | — |
| R And J Electric INC | Richard James Benzler | — | (925) 565 3968 | Electricians | Concord · Contra Costa County | — | — |
| R Avalos Painting | R Avalos Painting | — | (415) 350 1916 | Windows, patio, painters | Concord · Contra Costa County | — | — |
| R Bay Construction | Santillan Saul Buenrostro | — | (415) 760 7289 | GC, remodel, ADU | Richmond · Contra Costa County | — | — |
| R C Construction | Ray Bernard Cox | — | (650) 759 5237 | GC, remodel, ADU | San Ramon · Contra Costa County | — | — |
| R C Electric | Rick Jaime Carrillo | — | (925) 285 8036 | Electricians | Concord · Contra Costa County | — | — |
| R C Electric INC | Rick Coleman Crowell | — | (925) 332 5889 | Electricians | Concord · Contra Costa County | — | — |
| R C O General Construction | Roberto Carlos Orellana | — | (925) 436 9675 | GC, remodel, ADU | Hercules · Contra Costa County | — | — |
| R C Sausedo General Contractor | R C Sausedo General Contractor | — | (925) 250 4007 | GC, remodel, ADU | Martinez · Contra Costa County | — | — |
| R C Trim | R C Trim | — | (925) 783 2263 | Other | Oakley · Contra Costa County | — | — |
| R C Underground INC | Ryan Erle Caulfield | — | (925) 705 7499 | Other | Walnut Creek · Contra Costa County | — | — |
| R D Construction | Jamshid R Dinyari | — | (925) 899 1571 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| R D K Construction | Ronald David Kidd | — | (925) 314 5875 | GC, remodel, ADU | San Ramon · Contra Costa County | — | — |
| R Da Silva Construction | Robert Alexandre Da Silva | rdasilvaconst@gmail.com | (510) 260 4888 | GC, remodel, ADU | Pleasant Hill · Contra Costa County | — | — |
| R E A L Painting | R E A L Painting | — | (510) 758 5536 | Windows, patio, painters | El Sobrante · Contra Costa County | — | — |
| R F Clark Of San Francisco | Stephen Charles Clark | — | (415) 694 9963 | Electricians | Lafayette · Contra Costa County | — | — |
| R F Clark Of San Francisco INC | Stephen Charles Clark | — | (415) 694 9963 | GC, remodel, ADU | Lafayette · Contra Costa County | — | — |
| R F Construction Engineering | Ramirez-flores Felix | — | (415) 446 8828 | GC, remodel, ADU | Richmond · Contra Costa County | — | — |
| R F D Construction INC | Dominguez Ricardo Flores | — | (415) 999 6637 | GC, remodel, ADU | San Pablo · Contra Costa County | — | — |
| R F E Construction | Robert Frederick Jr Ergenbright | — | (510) 387 1334 | GC, remodel, ADU | El Cerrito · Contra Costa County | — | — |
| R F G General Contractor | R F G General Contractor | — | (510) 912 9349 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| R F I Construction Management INC | Mark Randall Greening | — | (925) 478 7999 | GC, remodel, ADU | Danville · Contra Costa County | — | — |
| R G C Construction INC | Anthony Paul Redfearn | build@rgcconstruction.com | (510) 640 7411 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| R G Construction | Gonzalez Ruiz Ricardo | — | (510) 759 4415 | GC, remodel, ADU | El Cerrito · Contra Costa County | — | — |
| R G Construction | Rick Gerard Gonzalez | — | (341) 837 8508 | GC, remodel, ADU | Pinole · Contra Costa County | — | — |