| Cast Property Painting Services | Ashley Consuelo Castaneda | — | (949) 572 8508 | Windows, patio, painters | Lake Forest · Orange County | — | — |
| Casta Pacific Pro Painting | Casta Pacific Pro Painting | — | (714) 727 4855 | Windows, patio, painters | Santa Ana · Orange County | — | — |
| Castagna Awnings | Castagna Awnings | — | (714) 374 7202 | Other | Huntington Beach · Orange County | — | — |
| Castagna Construction | George Vincent Castagna | — | (951) 870 3438 | Electricians | Santa Ana · Orange County | — | — |
| Castaways Landscape | Castaways Landscape | — | (949) 303 9579 | Windows, patio, painters | Dana Point · Orange County | — | — |
| Caste Painting | Caste Painting | — | (949) 374 4977 | Windows, patio, painters | San Juan Capistrano · Orange County | — | — |
| Castillo Builders | Castillo Builders | — | (949) 412 2733 | GC, remodel, ADU | Capistrano Beach · Orange County | — | — |
| Castillo Fausto | Castillo Fausto | — | (714) 394 3341 | GC, remodel, ADU | Fullerton · Orange County | — | — |
| Castillo Rock Concrete INC | Armando Castillo | — | (714) 725 0720 | Other | Stanton · Orange County | — | — |
| Castle Electric | Osman Jesus Castillo | goev@castleelectric.com | (714) 430 1444 | Electricians | Costa Mesa · Orange County | — | — |
| Castle Masonry & Pavers INC | Luigui Antonio Castillo | — | (949) 929 5640 | Other | Lake Forest · Orange County | — | — |
| Castleton Development And Management INC | John Wesley French | — | (714) 833 5454 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Castrejon Carpets | Castrejon Carpets | — | (714) 864 4933 | Other | Garden Grove · Orange County | — | — |
| Cata INC | Akoubian Kevork | — | (949) 340 5668 | Other | Newport Beach · Orange County | — | — |
| Catalan Golden Builders Corp | Christian Yordan Catalan Rodriguez | catalangoldenbuilders@gmail.com | (562) 384 6042 | GC, remodel, ADU | Lake Forest · Orange County | — | — |
| Catalan's Building Restoration | Catalan's Building Restoration | — | (714) 651 6628 | GC, remodel, ADU | Santa Ana · Orange County | — | — |
| Catalina Construction INC | Bryan Jim Zatica | — | (714) 863 4184 | Other | Santa Ana · Orange County | — | — |
| Catalina Mh INC | Hector Pinto | — | (562) 997 1911 | GC, remodel, ADU | Garden Grove · Orange County | — | — |
| Catalyst Construction | Wang Zhenhua | interested@domainmarket.com | (949) 279 6793 | GC, remodel, ADU | Irvine · Orange County | — | — |
| Catalyst Development | Catalyst Development | — | (714) 345 7718 | GC, remodel, ADU | Huntington Beach · Orange County | — | — |
| Catalyst Plumbing | Catalyst Plumbing | — | (562) 588 5980 | Other | Sunset Beach · Orange County | — | — |
| Catalyst Property Management - Orange County | Catalyst Property Management - Orange County | — | (714) 338-8877 | Property managers | Anaheim · Orange County | — | — |
| Catworks INC | Brent Leslie Chesser | — | (714) 269 6604 | Other | Cypress · Orange County | — | — |
| Cavanagh Construction | Pete Archibald Cavanagh | info@cavanaghconstruction.ie | (949) 357 7717 | GC, remodel, ADU | Capistrano Beach · Orange County | — | — |
| Cavendish Hydrogen | Blanca Carolina Andrade Vidal | — | (949) 469 7241 | GC, remodel, ADU | Irvine · Orange County | — | — |
| Cazarez Construction INC | Cazares Arturo | — | (714) 720 4397 | GC, remodel, ADU | Garden Grove · Orange County | — | — |
| Cb Construction Group INC | Burgos Ciro Montelongo | — | (714) 932 1536 | GC, remodel, ADU | Brea · Orange County | — | — |
| Cb Ember Hardening | Cb Ember Hardening | — | (949) 763 0594 | GC, remodel, ADU | San Clemente · Orange County | — | — |
| Cb General Contracting | Christopher Lee Black | — | (714) 609 4651 | GC, remodel, ADU | Buena Park · Orange County | — | — |
| Cbci Construction INC | Frank Eugene Blefari | — | (949) 542 7265 | Other roofers | Tustin · Orange County | — | — |
| Cbdi Flooring | Cbdi Flooring | — | (949) 338 4041 | GC, remodel, ADU | Laguna Niguel · Orange County | — | — |
| Cbgr Electric | Erik Abreu Sr Cardoso | — | (954) 839 4702 | Electricians | Laguna Beach · Orange County | — | — |
| Cc Plus INC DBA Advancer Construction | Jason Chen Chung Liu | — | (714) 459 5199 | GC, remodel, ADU | Fullerton · Orange County | — | — |
| Cc&e Companies | Tony Sungku Lee | — | (714) 215 4888 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Ccast Concrete INC | Jose Geovani Cruz Salinas | — | (951) 569 3110 | Other | Anaheim · Orange County | — | — |
| Ccc Builders | Edwin Curiel | — | (949) 619 3409 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| Ccd Flooring Solutions INC | Murguia Leslie Curi | — | (714) 662 6262 | Other | Laguna Hills · Orange County | — | — |
| Cce Construction INC | Benjamin Rouse Earl | contact@cce-construction.com | (949) 632 8894 | GC, remodel, ADU | Laguna Beach · Orange County | — | — |
| Ccm & Associates INC | Raul Silva Contreras | — | (714) 397 3720 | Other | Anaheim · Orange County | — | — |
| Ccm Construction INC | Peter Joonyeon Kim | — | (951) 220 6991 | GC, remodel, ADU | Orange · Orange County | — | — |