| Color - Me - Custom Painting | Thomas Joseph Reese | — | (714) 345 2611 | Windows, patio, painters | Lake Forest · Orange County | — | — |
| Color By Cowan | Color By Cowan | — | (714) 730 6543 | Windows, patio, painters | Santa Ana · Orange County | — | — |
| Color Copies & Banner & Signs | Jong Yoon Lee | — | (714) 742 8952 | Other | Garden Grove · Orange County | — | — |
| Color Painting Co | Sung Eun Han | — | (562) 755 9721 | Windows, patio, painters | Irvine · Orange County | — | — |
| Color Tech Painting | Color Tech Painting | — | (714) 469 4340 | Windows, patio, painters | Buena Park · Orange County | — | — |
| Colors And Coatings | Marcos Antonio Corvini | — | (562) 842 7377 | Windows, patio, painters | La Habra · Orange County | — | — |
| Colorview Landscape | Colorview Landscape | — | (714) 552 4616 | Windows, patio, painters | Garden Grove · Orange County | — | — |
| Colorworks Landscape Design INC | Jonathon David Hammel | — | (714) 833 3114 | Windows, patio, painters | Huntington Beach · Orange County | — | — |
| Colossal Excavation INC | Francisco Adam Garcia | — | (949) 257 3688 | Other | Garden Grove · Orange County | — | — |
| Colt Accessibility Products Inc/next Day Access | Eric Michael Smith | — | (714) 719 0691 | Other | Anaheim · Orange County | — | — |
| Colton Construction | Curtis Hale Colton | — | (760) 473 9533 | GC, remodel, ADU | Mission Viejo · Orange County | — | — |
| Colton James Kummer | Colton James Kummer | — | (949) 212 7095 | Other | San Clemente · Orange County | — | — |
| Colts Landscape INC | Alfredo Jose Jimenez | — | (714) 925 4187 | Windows, patio, painters | Garden Grove · Orange County | — | — |
| Columbine Landscapes | Columbine Landscapes | — | (714) 879 0169 | Windows, patio, painters | Fullerton · Orange County | — | — |
| Column 4 Construction Company | Ahmad Alvandi | — | (949) 420 1601 | GC, remodel, ADU | Newport Beach · Orange County | — | — |
| Colwell Concrete INC | Max Roger Colwell | — | (949) 275 0843 | Other | San Juan Capistrano · Orange County | — | — |
| Colwell Construction | Brad Roger Colwell | info@colwellconstruction.com | (949) 322 0556 | GC, remodel, ADU | Dana Point · Orange County | — | — |
| Com Door & Hardware INC | Milo Charles Weaver | — | (714) 633 9011 | GC, remodel, ADU | Orange · Orange County | — | — |
| Comax Construction Corporation | America A Jung | contact@sansoxygen.com | (562) 672 0153 | GC, remodel, ADU | Buena Park · Orange County | — | — |
| Combat Cleaning INC | Lindsay Clark Mathews | — | (949) 374 2672 | Other | Ladera Ranch · Orange County | — | — |
| Comeco Group INC | Antonio Manuel Carvalho | — | (949) 359 0866 | GC, remodel, ADU | Santa Ana · Orange County | — | — |
| Comet Lighting & Electric INC | Gregory Allen Renius | — | (714) 773 1859 | Electricians | Fullerton · Orange County | — | — |
| Comet Plumbing Co | Danny Dae Gil | — | (949) 254 3333 | Other | Irvine · Orange County | — | — |
| Comex Low Voltage Security Systems | Giovanni Andres Toscano Ruiz | — | (562) 646 2666 | Electricians | Anaheim · Orange County | — | — |
| Comfort Control Heating & Airconditioning | Comfort Control Heating & Airconditioning | — | (714) 273 3452 | HVAC | Anaheim · Orange County | — | — |
| Comfort Control HVAC | Martin Herrera | — | (714) 578 3838 | HVAC | Fullerton · Orange County | — | — |
| Comfort Cool Fans | David John Goodbrand | — | (949) 709 8194 | HVAC | Rancho Santa Margarita · Orange County | — | — |
| Comfort Cool Fans Manufacturer Direct Installer Orange County | Comfort Cool Fans Manufacturer Direct Installer Orange County | — | (800) 206-7928 | HVAC | Rancho Santa Margarita · Orange County | — | — |
| Comfort Elite HVAC | Comfort Elite HVAC | — | (714) 464-6622 | HVAC | Orange · Orange County | — | — |
| Comfort Guards Heating And Air Conditioning LLC | Ryan Kevin Cortes | — | (323) 898 9463 | HVAC | Anaheim · Orange County | — | — |
| Comfort Heating And Air Conditioning | Comfort Heating And Air Conditioning | — | (714) 335 7055 | HVAC | Mission Viejo · Orange County | — | — |
| Comfort Painting INC | Scott Allen Caldwell | — | (908) 963 8202 | Windows, patio, painters | San Juan Capistrano · Orange County | — | — |
| Comfort Pro | Tracy Kay Shimazu | — | (844) 289 8468 | Other | Newport Beach · Orange County | — | — |
| Comfort Solution Expert | Comfort Solution Expert | — | (714) 679 5220 | HVAC | Huntington Beach · Orange County | — | — |
| Comfort Solutions Heating And Cooling | Comfort Solutions Heating And Cooling | — | (714) 829 5605 | HVAC | Fullerton · Orange County | — | — |
| Command Air Corp | Christopher Lee Parker | — | (714) 952 3900 | HVAC | Fountain Valley · Orange County | — | — |
| Commercial Cable Services INC | James Andrew Allgood | — | (714) 335 1766 | Other | Huntington Beach · Orange County | — | — |
| Commercial Carpet & Flooring Services | Richard Joe Henderson | — | (714) 630 9085 | Other | Anaheim · Orange County | — | — |
| Commercial Coating | Commercial Coating | — | (949) 612 5442 | Windows, patio, painters | Costa Mesa · Orange County | — | — |
| Commercial Construction Company | William J Goodman | — | (714) 322 6496 | GC, remodel, ADU | Anaheim · Orange County | — | — |