| Advanced Entry Systems | Advanced Entry Systems | — | (714) 494 3084 | Other | Anaheim · Orange County | — | — |
| Advanced Equipment Corporation | Warren Scott Dickson | — | (714) 635 5350 | Other | Fullerton · Orange County | — | — |
| Advanced Filtration Concepts INC | John George Fintland | — | (323) 832 8316 | Other | Rancho Santa Margarita · Orange County | — | — |
| Advanced Geosolutions INC | Juan Ivan Baez | — | (310) 796 9000 | Other | Lake Forest · Orange County | — | — |
| Advanced Home Energy Solutions | Kevin Mathias Sullivan | — | (949) 540 1418 | HVAC | Orange · Orange County | — | — |
| Advanced Improvements INC | Jason Shawn Hayes | — | (714) 630 6611 | Other roofers | Anaheim · Orange County | — | — |
| Advanced Industrial Plumbing INC | Jeronimo Rodriguez | — | (760) 949 4909 | Other | Costa Mesa · Orange County | — | — |
| Advanced Industrial Services INC | Rex David Jr Johnston | — | (562) 940 8305 | GC, remodel, ADU | Los Alamitos · Orange County | — | — |
| Advanced Installations | Advanced Installations | — | (949) 633 8360 | GC, remodel, ADU | San Clemente · Orange County | — | — |
| Advanced Kitchen And Bath | Advanced Kitchen And Bath | — | (714) 983 8099 | Windows, patio, painters | Stanton · Orange County | — | — |
| Advanced Lan Techs INC | Singh Jasbindar | events@alticd.com | (949) 440 7000 | Electricians | Irvine · Orange County | — | — |
| Advanced Landscape By Warfield | Advanced Landscape By Warfield | — | (661) 860 9222 | Windows, patio, painters | Laguna Hills · Orange County | — | — |
| Advanced Medical Builders INC | Greg Scott Laube | — | (714) 634 4430 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Advanced Modular Construction | Sergiu Bogdan Andrei | — | (714) 225 8879 | GC, remodel, ADU | Garden Grove · Orange County | — | — |
| Advanced Pacific Landscape | Advanced Pacific Landscape | — | (951) 259 6412 | Windows, patio, painters | Dana Point · Orange County | — | — |
| Advanced Painting & Wood Repair | Gerry Russell Soneff | — | (949) 367 0060 | GC, remodel, ADU | Laguna Hills · Orange County | — | — |
| Advanced Plumbing | Advanced Plumbing | — | (714) 936 1499 | Other | Anaheim · Orange County | — | — |
| Advanced Plumbing INC | Steven James Lovell | — | (951) 733 9469 | Other | San Clemente · Orange County | — | — |
| Advanced Powering Services INC | Timothy William Scharf | — | (949) 215 3287 | Electricians | Rancho Santa Margarita · Orange County | — | — |
| Advanced Roofing And Roof Removal INC | Cindy Juliana Villa | — | (562) 986 3236 | Other roofers | La Habra · Orange County | — | — |
| Advanced Scratch Removal INC | Fernando Ruiz Chavez | — | (949) 331 2981 | Other | Laguna Beach · Orange County | — | — |
| Advanced Surfaces INC | Pedro Torres Medina | — | (714) 635 0949 | Other | Buena Park · Orange County | — | — |
| Advanced Systems Company | Michael David Workman | — | (760) 779 1352 | Other | San Clemente · Orange County | — | — |
| Advantage Audio Video | Advantage Audio Video | — | (714) 262 7717 | Other | Fullerton · Orange County | — | — |
| Advantage Door & Hardware INC | Kevin Lagos Steckler | — | (714) 532 3828 | GC, remodel, ADU | Orange · Orange County | — | — |
| Advantage Drywall Systems INC | Rick Gilbert Brown | — | (949) 553 8383 | Other | Tustin · Orange County | — | — |
| Advantage Flooring | Advantage Flooring | — | (562) 822 1541 | Other | La Habra · Orange County | — | — |
| Advantage Glass & Mirror Co | William Lauren Iii Blevins | — | (562) 690 3456 | Windows, patio, painters | La Habra · Orange County | — | — |
| Advantage H V A C | Advantage H V A C | — | (714) 350 8975 | HVAC | Anaheim · Orange County | — | — |
| Advantage Plus Energy Insulation | Advantage Plus Energy Insulation | — | (949) 361 9555 | Other | San Clemente · Orange County | — | — |
| Advantage Weed Abatement & Landscape Services | David Robert Dowell | — | (562) 746 6982 | Windows, patio, painters | La Habra · Orange County | — | — |
| Ae Construction | Ehsani Ali | — | (714) 679 4286 | GC, remodel, ADU | Huntington Beach · Orange County | — | — |
| Ae Solutions INC | David Drake Smith | — | (714) 841 5285 | Electricians | Huntington Beach · Orange County | — | — |
| Ae&f INC | Luis Enrique Elias-Molina | — | (657) 253 8454 | Other | Santa Ana · Orange County | — | — |
| Aea Construction & Remodeling LLC | Edith Erick Santana Uribe | — | (714) 450 2199 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Aec Development INC | Michael Mourice Michael | — | (949) 577 0174 | Electricians | Seal Beach · Orange County | — | — |
| Aec Engineering Corp | Bryan Franklin Dain | — | (714) 805 1982 | Other | Yorba Linda · Orange County | — | — |
| Aegis Builders INC | Brandon Earle Woodward | — | (714) 535 7999 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Aegis Construction Group INC | Jeffrey Richard Dunn | — | (714) 858 0656 | Electricians | Anaheim · Orange County | — | — |
| Aerosphere Electric | Muhammad Akram Diab | moediab@aerosphereelectric.com | (714) 499 6656 | HVAC | Fountain Valley · Orange County | — | — |