| Corvin Painting Jack L Corvin Jr | Jack Lee Jr Corvin | — | (619) 993 6509 | Windows, patio, painters | Escondido · San Diego County | — | — |
| Cory Swettenam | Cory Swettenam | — | (760) 594 2794 | Other | Vista · San Diego County | — | — |
| Cory Tatz Bathtubs & Sinks Refinishing | Cory Evan Tatz | — | (619) 464 5141 | Other | San Diego · San Diego County | — | — |
| Cosenza Roofing | Roberto Francisco Cosenza | matt@pixelspread.com | (619) 715 7358 | Other roofers | Lakeside · San Diego County | — | — |
| Cosgrove Electric Incorporated | Dana Patrick Cosgrove | — | (619) 933 2157 | Electricians | Lakeside · San Diego County | — | — |
| Cosmar Construction LLC | Marco Antonio Martinez Lugo | guy@infinitydesignbuild.com | (619) 674 4899 | GC, remodel, ADU | Escondido · San Diego County | — | — |
| Cosmic Electric And Data Systems INC | Julian Edward Yves Martinot | julian@cosmicelectrical.com | (951) 257 8209 | Electricians | Fallbrook · San Diego County | — | — |
| Cosmic Solar INC | Shadzi Bahram | bahram@cosmicsolar.com | (760) 749 1111 | Other roofers | Vista · San Diego County | — | — |
| Coss Construction Co | Steven Donald Coss | — | (619) 933 2656 | GC, remodel, ADU | Alpine · San Diego County | — | — |
| Coss Drywall | Coss Eglen | — | (619) 251 6545 | GC, remodel, ADU | Lemon Grove · San Diego County | — | — |
| Costa Azul Contracting Group | Jovan Joel Munoz | — | (619) 346 5388 | GC, remodel, ADU | San Diego · San Diego County | — | — |
| Costa Azul Painting | Costa Azul Painting | — | (760) 827 9150 | Windows, patio, painters | Carlsbad · San Diego County | — | — |
| Costa Del Sol Landscape INC | Gustavo| Garcia Gustavo Pecheco Garcia | — | (619) 279 6478 | Windows, patio, painters | Ramona · San Diego County | — | — |
| Costa Flooring INC | Vinicius Alvares Costa | — | (858) 900 6494 | Other | San Diego · San Diego County | — | — |
| Costa Pacific Contracting INC | Kevin Patrick Riley | conor@costa-pacific.com | (858) 900 1460 | GC, remodel, ADU | El Cajon · San Diego County | — | — |
| Costelow Glass & Door | Paul Andrew Costelow | — | (858) 699 3717 | Windows, patio, painters | San Diego · San Diego County | — | — |
| Cota Construction | Edgar Fermin Cota | buildzoomsupport@blockrenovation.com | (619) 366 4808 | Electricians | National City · San Diego County | — | — |
| Coti Developments INC | Steven Matthew Hoblin | scorrea@cotidevelopments.com | (760) 672 1111 | GC, remodel, ADU | Chula Vista · San Diego County | — | — |
| Cottrell Construction Company | Randy Lee Cottrell | — | (619) 504 2222 | GC, remodel, ADU | Escondido · San Diego County | — | — |
| Coughlin Windows & Doors INC | Gerald Robert Coughlin | — | (760) 737 5000 | Windows, patio, painters | Escondido · San Diego County | — | — |
| Coulter Communications | Coulter Communications | — | (858) 527 8826 | Other | Encinitas · San Diego County | — | — |
| Countertops 4 Less | Countertops 4 Less | — | (619) 596 0795 | Other | El Cajon · San Diego County | — | — |
| Countertops By Design DBA Stone Slab Countertops By Design | Jose Angel Murillo-Aldava | — | (619) 368 8213 | Other | El Cajon · San Diego County | — | — |
| Countertops Direct INC | Hector Raul Renteria | — | (619) 985 2857 | Other | El Cajon · San Diego County | — | — |
| Country Developers INC | Tyson August Snyder | aqremodeling2@gmail.com | (760) 274 7723 | GC, remodel, ADU | Campo · San Diego County | — | — |
| Countryside Plumbing INC | Bernard Norman Martin | — | (619) 454 2124 | Other | Alpine · San Diego County | — | — |
| Countrywide Cabinetry INC | Jonathan Paul Warcholik | — | (619) 596 6999 | GC, remodel, ADU | Lakeside · San Diego County | — | — |
| County Backflow | Andrew Thomas Hockenberry | info@countybackflow.com | (619) 920 7825 | Other | San Marcos · San Diego County | — | — |
| County Building Services INC | Allen Keith Hoag | — | (619) 579 1304 | GC, remodel, ADU | El Cajon · San Diego County | — | — |
| County Burner And Machinery Corp | Lisa Murry | — | (619) 282 7545 | HVAC | San Diego · San Diego County | — | — |
| County Digging Septic | Van Christopher Raster | — | (760) 497 3213 | Other | Alpine · San Diego County | — | — |
| Countywide Mechanical Systems LLC | Jason Charles Mcclanahan | — | (619) 449 9900 | HVAC | El Cajon · San Diego County | — | — |
| Couple-o-bucks | Michael Todd Buck | — | (858) 365 7335 | GC, remodel, ADU | San Diego · San Diego County | — | — |
| Court Concepts INC | Mark Jeffrey Copeland | — | (619) 390 1614 | Other | Santee · San Diego County | — | — |
| Courtesy Plumbing INC | Anton Samir Misleh | — | (858) 775 3760 | HVAC | San Diego · San Diego County | — | — |
| Courtside Construction | Scott Allen Risch | — | (760) 505 3612 | GC, remodel, ADU | Vista · San Diego County | — | — |
| Coutts Brothers Development INC | John Hugh Coutts | — | (858) 220 7111 | GC, remodel, ADU | San Marcos · San Diego County | — | — |
| Couture Construction | Owen Scott Couture | buildzoomsupport@blockrenovation.com | (619) 536 4154 | GC, remodel, ADU | Santee · San Diego County | — | — |
| Cova Build Studio INC | Morena Del Carmen Hernandez Majano | ericka@covabuildstudio.com | (760) 685 2474 | GC, remodel, ADU | Fallbrook · San Diego County | — | — |
| Cove Design Build INC | Patrick Owen Hayes | — | (858) 722 4230 | GC, remodel, ADU | Carlsbad · San Diego County | — | — |