| Current Electric | William Alexander Iii Boyd | — | (949) 588 3777 | Electricians | Lake Forest · Orange County | — | — |
| Current Electric | James Vincenzo Lombardo | — | (949) 279 1588 | Electricians | Costa Mesa · Orange County | — | — |
| Current Innovations Electric | Matthew Ronald Serb | — | (714) 928 8466 | Electricians | Los Alamitos · Orange County | — | — |
| Current Wave Electrical Services INC | Mohammed Shafik Nassar | — | (949) 372 9922 | Electricians | Irvine · Orange County | — | — |
| Curtis Martin R | Curtis Martin R | — | (949) 584 0464 | Pool | Laguna Hills · Orange County | — | — |
| Curtis Roofing | James Harvey Iii Curtis | jack@wffinbox.co.uk | (949) 206 9963 | Other roofers | Laguna Beach · Orange County | — | — |
| Custom & Professional Service | Jose Ignacio Garcia | — | (714) 524 5001 | Windows, patio, painters | Placentia · Orange County | — | — |
| Custom Adu Builder | Custom Adu Builder | contact@customadubuilder.com | (714) 488 3160 | GC, remodel, ADU | Fullerton · Orange County | — | — |
| Custom Air Conditioning INC | Huh Byung Ho | — | (562) 529 5452 | HVAC | Anaheim · Orange County | — | — |
| Custom Builders And Painting INC DBA Custom Construction | Jong Bum Kim | — | (714) 234 9198 | GC, remodel, ADU | Fullerton · Orange County | — | — |
| Custom Cabinetry Designs INC | Luis Alonso Sanchez Carrasco | — | (714) 931 4322 | Other | Anaheim · Orange County | — | — |
| Custom Carpentry INC | Paul Jarnutowski | — | (562) 694 1446 | Other | La Habra · Orange County | — | — |
| Custom Coatings & Finishes | Custom Coatings & Finishes | — | (949) 378 9575 | Windows, patio, painters | Mission Viejo · Orange County | — | — |
| Custom Colors By Rand | Custom Colors By Rand | — | (949) 290 4426 | Windows, patio, painters | Laguna Hills · Orange County | — | — |
| Custom Connection | Jason Brian Bernhardt | — | (949) 813 4844 | Electricians | Trabuco Canyon · Orange County | — | — |
| Custom Construction & Finishing | Randall Howard Magnon | — | (714) 636 1220 | GC, remodel, ADU | Garden Grove · Orange County | — | — |
| Custom Construction Plumbing INC | Galvan Ortiz Bernardo | — | (949) 547 4748 | Other | Lake Forest · Orange County | — | — |
| Custom Country Landscape Maintenance | Custom Country Landscape Maintenance | — | (949) 768 8635 | Windows, patio, painters | Laguna Hills · Orange County | — | — |
| Custom Cut Builders INC | Joel Anthony Norman | customcutbuilders@pacbell.net | (949) 644 4010 | GC, remodel, ADU | Newport Beach · Orange County | — | — |
| Custom Deluxe Landscape INC | Darwin Stephen Lewison | customdeluxeland@cox.net | (949) 498 5243 | GC, remodel, ADU | San Clemente · Orange County | — | — |
| Custom Design Incorporated | Floyd Burton Dalrymple | — | (310) 430 0956 | Other | Los Alamitos · Orange County | — | — |
| Custom Design Landscape Co | William Clifford Jr Bena | — | (714) 381 4184 | Windows, patio, painters | Garden Grove · Orange County | — | — |
| Custom Design Pro Tile INC | Penaloza Jose Acuna | — | (562) 416 5388 | Other | Anaheim · Orange County | — | — |
| Custom Dream Builders INC | Thai Thang Tran | — | (714) 902 8382 | Electricians | Garden Grove · Orange County | — | — |
| Custom Electrical Solutions INC | Lucian Stefah Dita | — | (714) 756 1574 | Electricians | Huntington Beach · Orange County | — | — |
| Custom Flooring By Brian | Brian George Brehm | — | (714) 928 5790 | Other | Yorba Linda · Orange County | — | — |
| Custom Flooring Designed By Arael | Custom Flooring Designed By Arael | — | (949) 278 3042 | Other | Buena Park · Orange County | — | — |
| Custom Framing Services INC | Alec Walter Walker | — | (714) 272 4173 | GC, remodel, ADU | Laguna Niguel · Orange County | — | — |
| Custom Granite INC | Ivan De Jesus Garcia Martinez | — | (562) 325 3881 | Other | Brea · Orange County | — | — |
| Custom H20 | Christopher Lee Mac Knight | — | (949) 484 3200 | Other | Brea · Orange County | — | — |
| Custom Heating And Air | Custom Heating And Air | — | (714) 596 9796 | HVAC | Huntington Beach · Orange County | — | — |
| Custom Iron Corporation | Michael Richard Knee | — | (949) 427 5210 | Other | Aliso Viejo · Orange County | — | — |
| Custom John's Plumbing | Custom John's Plumbing | — | (714) 936 1233 | Other | Huntington Beach · Orange County | — | — |
| Custom Lock And Key | Custom Lock And Key | — | (714) 788 9660 | Other | Tustin · Orange County | — | — |
| Custom Modular Services Corporation | Edward Joseph Mouawad | cmsc@custommodularservices.com | (714) 964 6834 | GC, remodel, ADU | Huntington Beach · Orange County | — | — |
| Custom Paint Works | Custom Paint Works | — | (949) 678 3289 | Windows, patio, painters | Laguna Hills · Orange County | — | — |
| Custom Painting And Decorating INC | Cesar Ventura Munoz Munoz | — | (714) 341 5261 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Custom Painting Co | Dong Hoon Shin | — | (562) 653 9533 | Windows, patio, painters | Fullerton · Orange County | — | — |
| Custom Painting N More INC | Jorge Luis B Mendoza | — | (714) 264 3045 | Windows, patio, painters | Santa Ana · Orange County | — | — |
| Custom Performance Floors INC | Russell Alan Patterson | — | (949) 929 9794 | Other | Huntington Beach · Orange County | — | — |