| Cogeneral Construction INC | Abd Elhadi Murad | charlexosorio@gmail.com | (650) 737 2354 | GC, remodel, ADU | Pacifica · San Mateo County | — | — |
| Coit Com Satellite Services INC | Kevin Leslie Miller | — | (650) 306 2500 | Other | Redwood City · San Mateo County | — | — |
| Coit Services INC | Robert Louis Kearn | — | (650) 697 5471 | GC, remodel, ADU | Burlingame · San Mateo County | — | — |
| Cole Construction | Brian Cole Younger | — | (650) 430 0594 | GC, remodel, ADU | Redwood City · San Mateo County | — | — |
| Colec LLC | Fahy Colman | — | (415) 948 4432 | Electricians | San Bruno · San Mateo County | — | — |
| Collins Construction | James Joseph Collins | — | (650) 867 0300 | GC, remodel, ADU | Redwood City · San Mateo County | — | — |
| Colman Daly Construction | Colman Mark Daly | — | (650) 302 4632 | GC, remodel, ADU | San Bruno · San Mateo County | — | — |
| Colonial Structural Iron | Colonial Structural Iron | — | (415) 971 0229 | Other | Brisbane · San Mateo County | — | — |
| Color Creations Painting Co | Ricardo Alfonso Azucena | — | (650) 438 9758 | Windows, patio, painters | So San Francisco · San Mateo County | — | — |
| Colorful Solutions INC | Douglas Alejandro Perez Patino | — | (650) 797 3580 | Windows, patio, painters | Daly City · San Mateo County | — | — |
| Colors Alive Painting | Colors Alive Painting | — | (650) 679 2383 | Windows, patio, painters | Redwood City · San Mateo County | — | — |
| Colors By Zoltan Painting | Colors By Zoltan Painting | — | (650) 556 9800 | Windows, patio, painters | Redwood City · San Mateo County | — | — |
| Colt Poncia Construction INC | Colten Paul Poncia | — | (650) 703 9559 | GC, remodel, ADU | Redwood City · San Mateo County | — | — |
| Colvin Mechanical | Colvin Mechanical | — | (650) 576 2184 | HVAC | Half Moon Bay · San Mateo County | — | — |
| Combine Roofing INC | Sepulveda Javier Ruan | — | (650) 271 0436 | Other roofers | Colma · San Mateo County | — | — |
| Comfort Zone Heating & Air Conditioning Co | Raymond Man - Kit Lui | — | (650) 520 6616 | HVAC | San Mateo · San Mateo County | — | — |
| Commando Plumbing | Commando Plumbing | commandoplumbing@gmail.com | (650) 690 4868 | Other | Menlo Park · San Mateo County | — | — |
| Common Interest Management Services | Common Interest Management Services | — | (877) 904-3080 | Property managers | San Mateo · San Mateo County | — | — |
| Community Reconstruction Solutions | George Edward Jr Perrenod | — | (650) 692 3030 | GC, remodel, ADU | Burlingame · San Mateo County | — | — |
| Complete Construction Solutions | Daniel Adam Hernandez | — | (415) 745 0895 | GC, remodel, ADU | South San Francisco · San Mateo County | — | — |
| Composite Restoration Co | Daskarolis Darin | — | (650) 400 5588 | GC, remodel, ADU | San Carlos · San Mateo County | — | — |
| Con-quest Contractors INC | Paul Nicholas Loukianoff | — | (415) 206 0524 | GC, remodel, ADU | Burlingame · San Mateo County | — | — |
| Concannon Construction INC | Ronan Eoin Concannon | — | (415) 298 7527 | GC, remodel, ADU | Daly City · San Mateo County | — | — |
| Condes Pro Painting | Condes Pro Painting | — | (650) 773 5484 | Windows, patio, painters | San Mateo · San Mateo County | — | — |
| Condon And Sons Lumber Co. | Condon And Sons Lumber Co. | — | (650) 349-3212 | Windows, patio, painters | San Mateo · San Mateo County | — | — |
| Coney Landscaping | Coney Landscaping | — | (650) 349 1651 | Windows, patio, painters | San Mateo · San Mateo County | — | — |
| Conneely Construction | Cathal Antoine Conneely | info@conneelyconstruction.com | (415) 305 0573 | GC, remodel, ADU | Daly City · San Mateo County | — | — |
| Connolly Brothers Glass | Connolly Brothers Glass | — | (650) 315 5746 | Windows, patio, painters | San Bruno · San Mateo County | — | — |
| Conoley Electric | Rhett David Conoley | — | (650) 906 9083 | Electricians | San Carlos · San Mateo County | — | — |
| Conrad Construction Co | Wojciechowski Conrad | — | (650) 302 1532 | Electricians | Burlingame · San Mateo County | — | — |
| Conrad's Builder | Conrad's Builder | — | (650) 669 3869 | GC, remodel, ADU | South San Francisco · San Mateo County | — | — |
| Conscapes INC | Richard Frank Iii Weil | info@conscapes.com | (650) 453 3288 | Windows, patio, painters | San Carlos · San Mateo County | — | — |
| Consolid INC | Jorge Luis Zambrano Patino | — | (650) 200 3251 | GC, remodel, ADU | San Mateo · San Mateo County | — | — |
| Constance L Ahern | Constance L Ahern | — | (650) 851 8006 | GC, remodel, ADU | Portola Valley · San Mateo County | — | — |
| Constantinos Tripsas | Constantinos Tripsas | — | (650) 678 2119 | GC, remodel, ADU | San Bruno · San Mateo County | — | — |
| Constru-y-dreams | Jose Andres Mora Villa | — | (650) 544 8217 | GC, remodel, ADU | San Mateo · San Mateo County | — | — |
| Construction General Maintenance Co | Boutros Sadalah Khoury | — | (415) 407 4434 | GC, remodel, ADU | Daly City · San Mateo County | — | — |
| Construction Unlimited | Massoudi Jahanbakhsh | — | (650) 678 7444 | GC, remodel, ADU | San Mateo · San Mateo County | — | — |
| Constructive Solutions INC | Rami George Tawasha | — | (650) 539 0900 | GC, remodel, ADU | San Mateo · San Mateo County | — | — |
| Control Fire INC | Jason Michael Leake | — | (650) 268 9928 | Other | Redwood City · San Mateo County | — | — |