| Western Construction & Remodeling INC | Paul Thomas Dennis | — | (925) 435 8699 | GC, remodel, ADU | Martinez · Contra Costa County | — | — |
| Western Restoration Company | Waheed Tamim Popal | — | (510) 396 9233 | GC, remodel, ADU | San Ramon · Contra Costa County | — | — |
| Western Scientific Fastserv INC | Logan Federick Mead | — | (925) 827 3092 | Other | Antioch · Contra Costa County | — | — |
| Western Sierra INC | Anthony Wayne Farber | rsullivan@western-sierra.com | (559) 970-3565 | Other roofers | Pacheco · Contra Costa County | — | — |
| Westframe General Construction | Deniz Alberto | — | (925) 297 7346 | GC, remodel, ADU | Bay Point · Contra Costa County | — | — |
| Westgate Builders | John Kueicho Chao | — | (510) 725 8470 | GC, remodel, ADU | Pinole · Contra Costa County | — | — |
| Westgate Painting | Westgate Painting | — | (925) 914 0483 | Windows, patio, painters | Concord · Contra Costa County | — | — |
| Westpro Painting | Westpro Painting | — | (925) 317 4494 | Windows, patio, painters | Pittsburg · Contra Costa County | — | — |
| Westpro Realty INC | Eric Bruce Meyers | — | (510) 233 5000 | GC, remodel, ADU | Pinole · Contra Costa County | — | — |
| Westwind Builders And Electric INC | Michael Wayne Rich | — | (925) 855 0540 | Electricians | Alamo · Contra Costa County | — | — |
| Wet Creations Pools & Spas INC | Terry Wayne Scarbrough | — | (925) 566 4505 | Pool | Oakley · Contra Costa County | — | — |
| Wet Painting | Wet Painting | — | (925) 383 3782 | Windows, patio, painters | Pacheco · Contra Costa County | — | — |
| Wgm Construction INC | Mely Evelin Villicana | — | (415) 368 4339 | GC, remodel, ADU | Richmond · Contra Costa County | — | — |
| Whit's Painting INC | Kelly Cuthbert Whitney | — | (925) 595 1096 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| Whitaker Plumbing And Mechanical | Brandon Nicholas Whitaker | — | (925) 783 5485 | Other | Oakley · Contra Costa County | — | — |
| White Crow Builder | White Crow Builder | — | (510) 685 3034 | GC, remodel, ADU | El Cerrito · Contra Costa County | — | — |
| White House Energy INC | Sean Blair White | — | (925) 482 4176 | Electricians | Orinda · Contra Costa County | — | — |
| White Magic Cleaning And Restoration INC | Aaron Tobias Ramos | — | (925) 935 4449 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| White Water Plumbing | Robert Edward Diaz | info@whitewaterplumbing.com | (925) 778 5629 | GC, remodel, ADU | Antioch · Contra Costa County | — | — |
| White's Reliable Electric INC | Brion Ferguson | — | (510) 237 6930 | Electricians | Richmond · Contra Costa County | — | — |
| Whiteside Construction Corporation | Michelle Ann Whiteside | info@whitesideconstruction.com | (510) 234 6681 | GC, remodel, ADU | Richmond · Contra Costa County | — | — |
| Whiting Glass INC | Dennis Lee Ii Whiting | — | (925) 332 5183 | Windows, patio, painters | Concord · Contra Costa County | — | — |
| Wholesale Floor Covering And Designs | Wholesale Floor Covering And Designs | — | (408) 309 8114 | Other | Brentwood · Contra Costa County | — | — |
| Wholly Construction | Anwar Noor Charlie | info@whollyconstruction.com | (925) 895 5637 | GC, remodel, ADU | San Ramon · Contra Costa County | — | — |
| Wiggenhauser Construction LLC | Wiggenhauser Uwe | — | (510) 303 1360 | GC, remodel, ADU | Brentwood · Contra Costa County | — | — |
| Wilbuild Const | Wilbuild Const | — | (925) 260 3228 | GC, remodel, ADU | Martinez · Contra Costa County | — | — |
| Wildfire Fighting Systems | John Allen Spencer | — | (925) 497 6190 | Other | Martinez · Contra Costa County | — | — |
| Wildland Corporation | William R Thorn | — | (925) 283 4949 | GC, remodel, ADU | Lafayette · Contra Costa County | — | — |
| Wildrose Gardens Sustainable Landscaping | Wildrose Gardens Sustainable Landscaping | — | (510) 681 9520 | Windows, patio, painters | El Cerrito · Contra Costa County | — | — |
| Wildwood Construction | David Hall Fair | interested@domainmarket.com | (510) 410 0202 | GC, remodel, ADU | Orinda · Contra Costa County | — | — |
| Wiley INC | Michael Robert Wiley | — | (925) 240 9227 | GC, remodel, ADU | Oakley · Contra Costa County | — | — |
| Will Huie DBA Trilogy Home Theater | Trilogy Home Theater | — | (925) 348 4293 | Other | Martinez · Contra Costa County | — | — |
| Will's Floor Covering | Will's Floor Covering | — | (925) 705 1447 | Other | Antioch · Contra Costa County | — | — |
| William Cruz Plumbing | William Cruz Plumbing | — | (510) 426 2811 | Other | Richmond · Contra Costa County | — | — |
| William Dew General Contractor | William Dew General Contractor | — | (510) 612 2218 | GC, remodel, ADU | El Cerrito · Contra Costa County | — | — |
| William Edward Reed | William Edward Reed | — | (925) 938 5840 | GC, remodel, ADU | Alamo · Contra Costa County | — | — |
| William Green | William Green | — | (510) 427 3559 | Other | San Ramon · Contra Costa County | — | — |
| William H Peacock | William H Peacock | — | (925) 408 3686 | GC, remodel, ADU | Lafayette · Contra Costa County | — | — |
| William Harold Cullum | William Harold Cullum | — | (925) 933 8809 | GC, remodel, ADU | Alamo · Contra Costa County | — | — |
| William Landers Construction Co | William Lamont Landers | — | (925) 260 3938 | GC, remodel, ADU | Lafayette · Contra Costa County | — | — |