| C & D Mechanical INC | Dina Michelle Vigil | — | (707) 708 1889 | HVAC | Benicia · Solano County | — | — |
| C B H Construction | Cole Blu Harris | — | (916) 769 6703 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| C B Young & Sons Plumbing | Craig Bryan Young | — | (707) 447 0313 | Other | Vacaville · Solano County | — | — |
| C Bates Electric LLC | Carlos Bernett Jr Bates | service@cbateselectric.com | (707) 386 2566 | Electricians | Fairfield · Solano County | — | — |
| C D I Development & Realty INC | Tristan Michelle Ruiz | — | (707) 224 7135 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| C D L Enterprises | Charles Edward Lovenguth | — | (707) 372 2414 | Other | Fairfield · Solano County | — | — |
| C E Toland & Son | Jason Edward Toland | — | (707) 249 0412 | Other | Benicia · Solano County | — | — |
| C G Coatings INC | Chavez Gerardo | — | (510) 340 8802 | Windows, patio, painters | Fairfield · Solano County | — | — |
| C Grimm Handyman Service | Craig M Grimm | — | (707) 470 6949 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| C L Construction | Cesar Facundo Lara-loza | — | (415) 720 5613 | GC, remodel, ADU | Vallejo · Solano County | — | — |
| C L S Electric | Nelson Antonio Rojas | sales@clselectric.com | (707) 631 6128 | Electricians | Fairfield · Solano County | — | — |
| C Mag Construction INC | Carlos Jiro'tobal Magistrado | — | (707) 333 6008 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| C O R Construction INC | Vargas Javier Cordova | — | (707) 580 0567 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| C Oliver Electrical INC | Celestino Lagi Oliver | — | (408) 469 0417 | Electricians | Vallejo · Solano County | — | — |
| C P Unlimited | C P Unlimited | eben@eyebytes.com | (707) 373 6666 | Electricians | Vacaville · Solano County | — | — |
| C S Marine Constructors INC | Kent Rasmussen | — | (707) 562 4100 | Other | Vallejo · Solano County | — | — |
| Cabinet Solutions | Cabinet Solutions | info@cabinetsolutions.com | (707) 310 5369 | Other | Vallejo · Solano County | — | — |
| Cag Investments INC DBA Global HVAC And Construction | Walter Clay Gardiner | — | (707) 886 8932 | HVAC | Vacaville · Solano County | — | — |
| Cal - Bay Service | Guido Christopher| Estrada Guido Jorge Estrada | calbayservicehvac@yahoo.com | (707) 746 8755 | HVAC | Benicia · Solano County | — | — |
| Cal - Tex Masonry INC | Jeff Alan Lostak | — | (707) 448 9566 | Other | Vacaville · Solano County | — | — |
| Cal Best Construction Co | Elijah Ndundah Mutuku | justin@calbestconstruction.com | (415) 302 8478 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Cal Custom Remodel & Construction | David Vincent Andrade | — | (707) 333 3777 | GC, remodel, ADU | Vallejo · Solano County | — | — |
| Cal Elite Builders & Cal Electric | Charlie Abalos Lapurga | — | (707) 422 4017 | Electricians | Fairfield · Solano County | — | — |
| Cal INC | Christina Suzanne Vargas | — | (707) 446 7996 | Other roofers | Vacaville · Solano County | — | — |
| Cal Roofing Systems INC | Robert Frederick Moy | calroofing@aol.com | (707) 447 3132 | Other roofers | Vacaville · Solano County | — | — |
| Cal State Paving | Cal State Paving | — | (707) 724 4701 | Other | Vacaville · Solano County | — | — |
| Cal West Enterprises INC | Jeffrey Ben Gress | — | (707) 208 2736 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Calascio Concrete | Calascio Concrete | — | (707) 592 8286 | Other | Vacaville · Solano County | — | — |
| Caldera Stone And Tile | Caldera Stone And Tile | — | (707) 242 4879 | Other | Vallejo · Solano County | — | — |
| Caldwell Landscaping | Caldwell Landscaping | — | (415) 531 1316 | Windows, patio, painters | Fairfield · Solano County | — | — |
| Calen Builders INC | Charlie Abalos Lapurga | — | (209) 688 9623 | GC, remodel, ADU | Suisun · Solano County | — | — |
| Calex Drywall INC | Patrick Steven Malta Mendonca | office@calexdrywall.com | (707) 880 8600 | Other | Vacaville · Solano County | — | — |
| Cali Con Construction | Raygina Romaine Fox | — | (510) 393 1474 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Cali Leon Drywall | Cali Leon Drywall | — | (707) 724 0517 | Other | Dixon · Solano County | — | — |
| Caliber Novaa INC | Gurpartap Singh | estimating@calibernovaa.com | (707) 213 8081 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Calidad Construction | Rodriguez Antonio | — | (707) 553 2934 | GC, remodel, ADU | Vallejo · Solano County | — | — |
| California Contracting | Jonathan David Sparks | interested@domainmarket.com | (707) 564 0760 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| California Electrical Solutions | Noel Curtis Ward | — | (925) 270 3415 | Electricians | Benicia · Solano County | — | — |
| California Erectors INC | John George Konechne | — | (707) 746 1990 | Other | Benicia · Solano County | — | — |
| California Flooring INC | Timothy Jacob Klyberg | — | (707) 249 8108 | GC, remodel, ADU | Vacaville · Solano County | — | — |