| Cal-breeze Heating & Air Conditioning LLC | Zalmai Aiamodin | — | (925) 413 3120 | HVAC | Dublin · Alameda County | — | — |
| Cal-oak Constructors INC | Terrence Wayne Gilfillian | — | (415) 910 9596 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Cal-tech Plumbing Co | Travis Ira Robinson | caltechplumbinganddrains@gmail.com | (510) 648 6884 | Other | Union City · Alameda County | — | — |
| Cal-valley Painting INC | Michael William Treloar | — | (510) 418 2875 | Windows, patio, painters | Castro Valley · Alameda County | — | — |
| Cal-west Concrete Cutting INC DBA National Concrete Cutting | Marvin Weldon Birch | — | (510) 656 0253 | Other | Union City · Alameda County | — | — |
| Calco Fence INC | Scott E Pope | — | (925) 449 5081 | Other | Livermore · Alameda County | — | — |
| Calco Fence Supply INC | Mark Jacob Csicsery | — | (925) 449 5081 | Other | Livermore · Alameda County | — | — |
| Caldecott Construction LLC | David Daniel Clahan | — | (510) 418 3817 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Caldecott Retrofit Partners Jv | Engineering Contractors INC California | — | (925) 461 1500 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| Caldera Electric | Daniel Edward Schwartz | — | (510) 319 7099 | Electricians | Berkeley · Alameda County | — | — |
| Calderon Floors | Calderon Floors | — | (510) 776 0846 | Other | Oakland · Alameda County | — | — |
| Calenergy Electrical Corporation | Collin James Weiner | support@calenergycorp.com | (925) 922 2606 | Electricians | Livermore · Alameda County | — | — |
| Cali Pro Garage Door Service LLC | Tuan Anh Nguyen | — | (341) 777 5427 | Other | Hayward · Alameda County | — | — |
| Cali Roofs Commercial & Residential Roofing INC | Taylor Leigh Leinenweaver | — | (510) 383 0469 | Other roofers | Hayward · Alameda County | — | — |
| Cali Tint | Cali Tint | — | (925) 828 2600 | Other | Dublin · Alameda County | — | — |
| Cali'z Plumbing INC | Benjamin James Caliz | — | (510) 423 3141 | Other | Livermore · Alameda County | — | — |
| Caliber Cabinets INC | Giannecchini Michael | — | (925) 292 9124 | Other | Livermore · Alameda County | — | — |
| Caliber Window Coverings LLC | Kellie Sue Consolino | anapbm@gmail.com | (925) 967 5072 | Other | Dublin · Alameda County | — | — |
| Calif Construction | Juan Heriberto Diaz | — | (510) 703 4059 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Califer Construction | Esmaeil Rahimikhoshtinat | eben@eyebytes.com | (650) 452 5050 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| California Builders | California Builders | — | (510) 931 8177 | Electricians | San Leandro · Alameda County | — | — |
| California Construction | Panos Truong Ly | — | (510) 533 9888 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| California Contract Carpets INC | Stephanie K Ingram | — | (925) 828 7810 | Other | Dublin · Alameda County | — | — |
| California Custom Carpets INC | Stephanie K Ingram | — | (925) 828 7810 | Other | Dublin · Alameda County | — | — |
| California Custom Carpets INC Hatfield Tile | Custom Carpets INC California | — | (925) 828 7810 | Other | Dublin · Alameda County | — | — |
| California Dreamin Builders | Thomas Don Harney | — | (510) 827 9890 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| California Emergency Services | James Jennings Vaughn | — | (510) 785 0102 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| California Engineering Contractors INC | Lili A Tadros | — | (925) 461 1500 | Other | Pleasanton · Alameda County | — | — |
| California Engineering Contractors INC / Silverado Contractors | Engineering Contractors INC California | — | (925) 461 1500 | Other | Pleasanton · Alameda County | — | — |
| California Fence Builder | Luciano Andre Zelvaggio | sales@californiafencebuilder.com | (925) 339 4339 | Windows, patio, painters | Livermore · Alameda County | — | — |
| California Finest Windows | Jose Guadalupe Naranjo Barajas | info@californiafinestwindows.com | (510) 695 9197 | Windows, patio, painters | Hayward · Alameda County | — | — |
| California HVAC | Jorge Enrique Roedan | — | (510) 798 2123 | HVAC | Oakland · Alameda County | — | — |
| California Hydronics Corporation | Robert Allen Polizzi | — | (510) 293 1993 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| California Plumbing & Radiant Heating INC | Gerald Samuel Mairena | — | (510) 444 3992 | HVAC | Oakland · Alameda County | — | — |
| California Pool Construction INC | Rodriguez Manuel | — | (925) 872 8106 | Pool | Livermore · Alameda County | — | — |
| California Rebuilders | California Rebuilders | — | (510) 853 1800 | GC, remodel, ADU | Albany · Alameda County | — | — |
| California Renovations And Construction Company | Behrooz Ghorbani Tehrani | — | (510) 584 1780 | GC, remodel, ADU | Piedmont · Alameda County | — | — |
| California Scaffold Services INC | Saifullah Lodhi | — | (925) 461 1500 | Other | Pleasanton · Alameda County | — | — |
| California Seamless Gutters | California Seamless Gutters | — | (510) 919 3463 | Other | Livermore · Alameda County | — | — |
| California Textiles INC | Bradford Dean Ii Anrig | — | (510) 794 1172 | Other | Hayward · Alameda County | — | — |