| W C Drilling INC | Eugene William Lamont | — | (510) 245 0556 | Other | Pinole · Contra Costa County | — | — |
| W C J Electric INC | William Christian John | — | (510) 435 1217 | Electricians | Richmond · Contra Costa County | — | — |
| W C Services | James Matthew Daly | — | (925) 932 5678 | GC, remodel, ADU | Walnut Creek · Contra Costa County | — | — |
| W E Lyons Construction Co | Gregory Everett| Lyons Everett Gregory Lyons | — | (925) 658 1600 | GC, remodel, ADU | Walnut Creek · Contra Costa County | — | — |
| W Electric Construction | Wilmar Andres Loaiza Munoz | — | (954) 982 5583 | Electricians | Concord · Contra Costa County | — | — |
| W Foster & Company | William Foster Lowe | — | (925) 984 6156 | GC, remodel, ADU | Danville · Contra Costa County | — | — |
| W I Construction | Wilfredo Ricardo Iparraguirre | — | (925) 595 8710 | GC, remodel, ADU | Pittsburg · Contra Costa County | — | — |
| W J Blue Construction Co | Michael Kneeland Fuller | — | (510) 323 5530 | GC, remodel, ADU | El Cerrito · Contra Costa County | — | — |
| W J Goike Construction | William Joseph Goike | — | (510) 334 8612 | GC, remodel, ADU | Crockett · Contra Costa County | — | — |
| W R Forde Associates INC | Candace Marie Clapp | — | (510) 215 9338 | GC, remodel, ADU | Richmond · Contra Costa County | — | — |
| W S B Construction INC DBA Water Works Plumbing | William Scot Bergren | — | (925) 788 3815 | GC, remodel, ADU | Pleasant Hill · Contra Costa County | — | — |
| W S G Plumbing Solutions | Tamayo Jesus Martinez | — | (925) 238 1711 | Other | Antioch · Contra Costa County | — | — |
| Wa Architectural Design And Construction | Wafaa Almahamid | — | (925) 360 0552 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| Wadsworth Glass INC | Veronica Noemi Jerge | info@wadsworthglass.com | (510) 223 7380 | Windows, patio, painters | El Sobrante · Contra Costa County | — | — |
| Wailea Construction | Varasteh Ali | — | (650) 465 0436 | GC, remodel, ADU | Orinda · Contra Costa County | — | — |
| Walco | William Russell Walsh | — | (925) 567 4238 | Other | Concord · Contra Costa County | — | — |
| Walk In Bath Expert | Walk In Bath Expert | — | (925) 219 5930 | GC, remodel, ADU | Brentwood · Contra Costa County | — | — |
| Walker's Plumbing Services | Manuel Paul Jr Walker | — | (510) 837 1588 | Other | Richmond · Contra Costa County | — | — |
| Wall 2 Wall Construction INC | Chavez Jesus | — | (925) 339 2276 | GC, remodel, ADU | Bay Point · Contra Costa County | — | — |
| Wall-2-wall Construction LLC | Janatpour Monty | — | (510) 908 3680 | GC, remodel, ADU | Danville · Contra Costa County | — | — |
| Wallace Electric | Gordon Bradly Wallace | — | (925) 383 9219 | Electricians | Antioch · Contra Costa County | — | — |
| Wallace Termite And Construction | David Lee Wallace | — | (925) 706 2424 | GC, remodel, ADU | Antioch · Contra Costa County | — | — |
| Waller INC | Michael George Waller | info@waller.com | (925) 634 3663 | Other | Brentwood · Contra Costa County | — | — |
| Walnut Creek Construction And Remodeling Company | Hugh Matthew Walpole | — | (925) 497 2687 | GC, remodel, ADU | Alamo · Contra Costa County | — | — |
| Walnut Creek Fireplace INC | Ryan John Langdon | owner@walnutcreekfireplace.com | (925) 278 1400 | Other | Walnut Creek · Contra Costa County | — | — |
| Walnut Creek Heating And Air Conditioning | Brian Lloyd Waskow | — | (925) 933 9333 | HVAC | Concord · Contra Costa County | — | — |
| Walnut Creek Roofing INC DBA Building Services | Jason Lee Paulsen | — | (925) 934 4842 | Other roofers | Walnut Creek · Contra Costa County | — | — |
| Walsh Custom Construction | Wayne David Walsh | — | (925) 421 9712 | GC, remodel, ADU | Brentwood · Contra Costa County | — | — |
| Walt's Quality Painting | Walt's Quality Painting | — | (925) 516 0459 | Windows, patio, painters | Brentwood · Contra Costa County | — | — |
| Walter J Jackson | Walter J Jackson | — | (925) 787 8487 | GC, remodel, ADU | Pleasant Hill · Contra Costa County | — | — |
| Walter L Evans Painting | Walter L Evans Painting | — | (925) 432 2726 | Windows, patio, painters | Pittsburg · Contra Costa County | — | — |
| Walter Langhammer INC | Langhammer Walter | — | (925) 548 3886 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| Walton & Co LLC | Jake Havely Walton | info@walton.com | (415) 847 2274 | GC, remodel, ADU | Richmond · Contra Costa County | — | — |
| Waraner & Company LLC | Dustin Raymond Waraner | — | (925) 250 0334 | Windows, patio, painters | Clayton · Contra Costa County | — | — |
| Ward Company Contracting | Kevin William Ward | info@wardcontracting.com | (510) 685 3315 | GC, remodel, ADU | El Sobrante · Contra Costa County | — | — |
| Ward Construction INC | Arthur Stanley Ward | — | (510) 215 3636 | Other roofers | Richmond · Contra Costa County | — | — |
| Wardo Painting INC | Sava Bjelogrlic | — | (925) 457 8121 | Windows, patio, painters | Walnut Creek · Contra Costa County | — | — |
| Warford Construction Incorporated | Kraig Marshall Warford | — | (925) 429 3077 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| Warnock Construction | Kristopher Ryan Warnock | — | (925) 553 4080 | GC, remodel, ADU | Danville · Contra Costa County | — | — |
| Warranted Plumbing Services INC DBA Warranted Plumbing Services | Luis Alberto Chavez Perez | — | (925) 291 2627 | Other | Concord · Contra Costa County | — | — |