| C & G Laboratory Construction | Jimmy Lee Grimes | — | (213) 885 9834 | GC, remodel, ADU | Westminster · Orange County | — | — |
| C & H Construction Co | Roberta Lynn Crowder | — | (714) 549 9281 | GC, remodel, ADU | Santa Ana · Orange County | — | — |
| C & H Industries INC | Edward Gerard Clark | — | (714) 325 2427 | Other | Huntington Beach · Orange County | — | — |
| C & L Electrical | Christopher Wayne Curtis | — | (714) 381 3186 | Electricians | Stanton · Orange County | — | — |
| C & L Refrigeration Corporation | Lawrence Fredrick Jaslove | — | (800) 901 4822 | HVAC | Brea · Orange County | — | — |
| C & L Restoration INC | Christian Alberto Barrera | — | (714) 643 3336 | GC, remodel, ADU | Fullerton · Orange County | — | — |
| C & M Builders INC | Tyler Justin Garner | — | (949) 707 1697 | GC, remodel, ADU | Laguna Hills · Orange County | — | — |
| C & M Kitchen Cabinets INC | Marcel Boulanger | — | (714) 556 7312 | GC, remodel, ADU | Fountain Valley · Orange County | — | — |
| C & R Construction | Carlos Alex Rodriguez | — | (626) 384 1960 | GC, remodel, ADU | Brea · Orange County | — | — |
| C & R Drains INC | Kim Andree Mable Melrose | — | (714) 641 1545 | Other | Costa Mesa · Orange County | — | — |
| C & R Plumbing | C & R Plumbing | — | (949) 722 6401 | HVAC | Costa Mesa · Orange County | — | — |
| C & R Property Service | David Allen Tedeschi | — | (714) 417 7222 | Windows, patio, painters | Orange · Orange County | — | — |
| C & W Garage Doors | Werner Siegfried Wilke | — | (714) 258 9058 | Other | Tustin · Orange County | — | — |
| C - 42 Systems | Gary Herman Romberg | — | (714) 883 3951 | Other | Yorba Linda · Orange County | — | — |
| C - Ross The Plumber | C - Ross The Plumber | — | (714) 631 4274 | Other | Orange · Orange County | — | — |
| C A & A Tree Care INC | Yakelin Coreas Vigil | — | (714) 595 3363 | Tree | Garden Grove · Orange County | — | — |
| C A F Services INC | Eliseo Junior Jr Ochoa | — | (714) 365 6175 | Other | Garden Grove · Orange County | — | — |
| C A Granger Construction INC | Clyde Allen Jr Granger | — | (714) 642 8714 | GC, remodel, ADU | Orange · Orange County | — | — |
| C A Louw Construction Co | Clifford Andrew Louw | — | (949) 646 4229 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| C A Plumbing INC | Arroyo Edgar Cervantes | — | (714) 769 5908 | Other | Orange · Orange County | — | — |
| C A T Exteriors INC DBA C A T Builders | Ryan Taylor Connet | — | (619) 944 3778 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| C B I Consulting And Construction Mgmt INC | John Keith Daniels | — | (949) 598 4544 | GC, remodel, ADU | Laguna Hills · Orange County | — | — |
| C B S Construction Services INC | A Tony| Khodabandehloo Ahmad Khodabandehloo | — | (714) 840 2000 | GC, remodel, ADU | Huntington Beach · Orange County | — | — |
| C B Tile & Stone | C B Tile & Stone | — | (714) 717 6647 | Other | Huntington Beach · Orange County | — | — |
| C C B Landscape Services INC | Chapman Christopher Burke | — | (888) 416 0840 | Windows, patio, painters | Yorba Linda · Orange County | — | — |
| C C C C Heating & Air Conditioning INC | Charles Robert Nance | — | (714) 637 7021 | HVAC | Orange · Orange County | — | — |
| C C D L Investments INC | Chad Edward Carney | — | (949) 481 7920 | GC, remodel, ADU | San Clemente · Orange County | — | — |
| C C D Services INC | Clarence Donald Perr | — | (714) 458 3272 | Electricians | Brea · Orange County | — | — |
| C C Framing | C C Framing | — | (909) 586 7065 | GC, remodel, ADU | Fullerton · Orange County | — | — |
| C C K Builders INC | Lindsey Louise Radant | — | (714) 538 8200 | GC, remodel, ADU | Orange · Orange County | — | — |
| C C M Construction & Management INC | Eric Michael Papa | — | (949) 280 1508 | GC, remodel, ADU | Laguna Beach · Orange County | — | — |
| C C M R | C C M R | — | (951) 906 4100 | GC, remodel, ADU | San Clemente · Orange County | — | — |
| C D Construction | Cecil Dan Holland | — | (949) 500 3462 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| C D G Builders INC | Christopher Ryan De Fazio | — | (949) 892 3510 | GC, remodel, ADU | Irvine · Orange County | — | — |
| C D V Builders | C D V Builders | — | (657) 657 8887 | GC, remodel, ADU | Westminster · Orange County | — | — |
| C D V Builders INC | Minh Hoang Tran | — | (714) 699 3576 | GC, remodel, ADU | Westminster · Orange County | — | — |
| C E Contracting INC | Christopher Noble Everett | — | (714) 719 2818 | Electricians | Yorba Linda · Orange County | — | — |
| C F C Construction | Calixto Flores-Cortes | — | (949) 642 1706 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| C F E Manufacturing INC | George Elias Aboumerhi | — | (714) 998 1111 | HVAC | Orange · Orange County | — | — |
| C F M Electric INC | Caro Fabian Munoz | — | (714) 271 6852 | Electricians | Garden Grove · Orange County | — | — |