| Cielo Construction | Cielo David | — | (949) 280 6264 | GC, remodel, ADU | Trabuco Canyon · Orange County | — | — |
| Cik Power Distributors LLC | Sean Francis Lenahan | — | (714) 716 7165 | GC, remodel, ADU | Orange · Orange County | — | — |
| Cima C M & D | Javier Peraza Candelaria | — | (714) 285 1919 | GC, remodel, ADU | Garden Grove · Orange County | — | — |
| Cimabue Construction | Cimabue Christine | — | (714) 369 0888 | GC, remodel, ADU | Huntington Beach · Orange County | — | — |
| Cindy Evans Voorhees | Cindy Evans Voorhees | — | (714) 345 1353 | GC, remodel, ADU | Newport Beach · Orange County | — | — |
| Cinema Solution | Cinema Solution | — | (949) 436 3166 | Other | San Clemente · Orange County | — | — |
| Cintas Fire Protection | Jason Robert Dupuis | — | (714) 646 2554 | Electricians | Anaheim · Orange County | — | — |
| Circle Airflow Heating And Air Conditioning | Sean Trung Bui | — | (714) 251 3456 | HVAC | Garden Grove · Orange County | — | — |
| Circle City Cabinets | David Allan Drew | — | (714) 282 1251 | Other | Orange · Orange County | — | — |
| Circle Controls Electric INC | Joaquin Rodrigo Campos | — | (714) 615 8678 | Electricians | Laguna Hills · Orange County | — | — |
| Circle M Contractors INC | Rick Edward Mercier | — | (949) 888 9990 | GC, remodel, ADU | Rancho Santa Margarita · Orange County | — | — |
| Circle Square Construction | Hoa Van Nguyen | — | (510) 499 4033 | GC, remodel, ADU | Huntington Beach · Orange County | — | — |
| Circuit Pro Electric | Luis Ruiz Villalobos | — | (949) 257 5609 | Electricians | Mission Viejo · Orange County | — | — |
| Cirenio Gonzalez | Cirenio Gonzalez | — | (714) 356 9461 | Windows, patio, painters | Santa Ana · Orange County | — | — |
| Ciriaco Painting | Martinez Ruben Ciriaco | — | (714) 334 0409 | Windows, patio, painters | Garden Grove · Orange County | — | — |
| Cirus Development Co INC | Michael Grant Sullivan | — | (949) 852 5575 | GC, remodel, ADU | Newport Beach · Orange County | — | — |
| Cis Roofing | Marcus Ian Clinco | info@cisroofing.com | (714) 867 9178 | Other roofers | Mission Viejo · Orange County | — | — |
| Cisco Construction | Juan Carlos Ramirez | — | (714) 557 2788 | GC, remodel, ADU | Santa Ana · Orange County | — | — |
| Cisneros Builder Engineering | Cisneros Builder Engineering | — | (562) 481 7831 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| Citi Electric | Frank Ki Kim | — | (714) 856 3373 | Electricians | Fullerton · Orange County | — | — |
| Citil & Partners Construction INC | Ramazan Koyuncu | — | (213) 326 4386 | GC, remodel, ADU | Newport Beach · Orange County | — | — |
| Citivest Group | Robert John Compean | — | (949) 955 2855 | GC, remodel, ADU | Newport Beach · Orange County | — | — |
| Citivest INC | Daniel Edward Blackburn | — | (949) 474 0440 | GC, remodel, ADU | Newport Beach · Orange County | — | — |
| Citizen Services Painting | Zarif Mohamad Zafary | — | (714) 501 5877 | Windows, patio, painters | Tustin · Orange County | — | — |
| Citrus Plumbing LLC | Gonzalez Hector Quintana | — | (949) 374 9779 | Other | San Juan Capistrano · Orange County | — | — |
| City Construction | Dennis Lee Givens | — | (714) 318 7870 | GC, remodel, ADU | Orange · Orange County | — | — |
| City Green Oc INC | Lydia Ann Monroe | — | (714) 305 3176 | Windows, patio, painters | Costa Mesa · Orange County | — | — |
| City Lift Building Services INC | Timmy Alvin Varbel | — | (909) 868 0001 | Other | Coto De Caza · Orange County | — | — |
| City Lock & Key | City Lock & Key | — | (714) 978 1478 | Other | Anaheim · Orange County | — | — |
| City Pool And Spa Services | Gregorio Rodriguez | — | (714) 662 9279 | Pool | Santa Ana · Orange County | — | — |
| City Roofing & Maintenance INC | Christine Marie Walker | — | (949) 500 3648 | Other roofers | Newport Beach · Orange County | — | — |
| City Service Paving | Emily Christine Beach | — | (714) 632 6610 | Other | Placentia · Orange County | — | — |
| City Ventures Construction INC | Brandon Joe Scamihorn | — | (949) 258 7555 | GC, remodel, ADU | Irvine · Orange County | — | — |
| Cityscape Doors INC | Joseph Mark Pinkston | — | (949) 515 8363 | Other | Costa Mesa · Orange County | — | — |
| Cityview Contracting | Richard Andrew Sanchez | — | (714) 795 4301 | Other | Santa Ana · Orange County | — | — |
| Civarc Builders INC | Ramin Samie | — | (310) 597 2275 | GC, remodel, ADU | Irvine · Orange County | — | — |
| Civicpoint Construction INC | Khai Duy Dao | — | (714) 657 5578 | GC, remodel, ADU | Midway City · Orange County | — | — |
| Civil Earth | Civil Earth | — | (714) 312 6568 | GC, remodel, ADU | Yorba Linda · Orange County | — | — |
| Cj Air Conditioning & Heating Company | Charles John Manderville | — | (562) 505 7843 | HVAC | Laguna Woods · Orange County | — | — |
| Cj Shores Construction | Courtney Nicole Ciurej | — | (979) 204 0218 | GC, remodel, ADU | Huntington Beach · Orange County | — | — |