| Aguilar Painting | Aguilar Painting | — | (949) 861 1261 | Windows, patio, painters | Laguna Beach · Orange County | — | — |
| Aguilar Painting INC | Luis Alberto Aguilar Diaz | — | (714) 341 3538 | Windows, patio, painters | Anaheim · Orange County | — | — |
| Aguilera Construction INC | Aguilera Javier | — | (707) 495 3932 | Other roofers | Laguna Hills · Orange County | — | — |
| Aha Development Group INC | Matthew Scott Watson | — | (949) 612 9170 | GC, remodel, ADU | Laguna Beach · Orange County | — | — |
| Ahd Roofing & General Contractor Co | Delgado Andres Hernandez | — | (714) 767 7458 | Other roofers | Santa Ana · Orange County | — | — |
| Ahmad Moghadas | Ahmad Moghadas | — | (949) 573 6595 | GC, remodel, ADU | Irvine · Orange County | — | — |
| Ahmad Tajik DBA Alpha Design Group | Tajik Ahmad | — | (714) 234 0073 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Ahs Development Corp | Raymond Charles Sutton | — | (707) 695 6037 | GC, remodel, ADU | Laguna Beach · Orange County | — | — |
| Ai Home INC | Lin Pengcheng | — | (800) 778 5576 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Ai-tek | Michael Mann | — | (714) 847 8445 | Electricians | Huntington Beach · Orange County | — | — |
| Aice Remodeling | Quezada Eliel Camargo | — | (714) 860 8815 | GC, remodel, ADU | Santa Ana · Orange County | — | — |
| Aik Construction Company | Alfredo Alvarez-Trejo | — | (714) 306 0770 | GC, remodel, ADU | Santa Ana · Orange County | — | — |
| Aim Construction | Abdul Murad | — | (310) 757 1888 | GC, remodel, ADU | Irvine · Orange County | — | — |
| Aim Ornamental INC | Aurelio Ivan Martinez | — | (949) 844 1544 | Other | Santa Ana · Orange County | — | — |
| Ainos Electric INC | Gyeong Cheol Lee | — | (949) 533 4788 | Electricians | Buena Park · Orange County | — | — |
| Air Assistance | Air Assistance | — | (949) 276 1555 | HVAC | Mission Viejo · Orange County | — | — |
| Air Blue HVAC | Siarhei Znak | — | (949) 943 0137 | HVAC | Santa Ana · Orange County | — | — |
| Air Care Experts | Nicholas Evan Mccabe | — | (949) 632 5085 | HVAC | Lake Forest · Orange County | — | — |
| Air Care Heating & Air Conditioning INC | Juny Ernesto Campos | — | (949) 482 2911 | HVAC | Rancho Santa Margarita · Orange County | — | — |
| Air Choum Heating & Air | Air Choum Heating & Air | — | (714) 321 4707 | HVAC | Orange · Orange County | — | — |
| Air Cleaning Technology | Robert Paul Krause | sales@aircleaningtechnology.com | (714) 641 5005 | HVAC | Santa Ana · Orange County | — | — |
| Air Concepts | Kelly Mae Gleason | info@airconcepts.com | (714) 779 1000 | HVAC | Anaheim · Orange County | — | — |
| Air Conditioning Services Of California INC | Robin Kim Lawr | — | (949) 305 8701 | HVAC | Laguna Hills · Orange County | — | — |
| Air Control Solutions | Air Control Solutions | — | (714) 657 2589 | HVAC | Orange · Orange County | — | — |
| Air Cool & Fast | Marco Aurelio Mondragon | — | (714) 675 8906 | HVAC | Garden Grove · Orange County | — | — |
| Air Flow Bros LLC | Alvin Glenn Chua Sornsaard | — | (657) 226-1476 | HVAC | Tustin · Orange County | — | — |
| Air Flow Control Air Jv | Flow Mechanical INC Air | — | (714) 777 8600 | HVAC | Anaheim · Orange County | — | — |
| Air Flow Mechanical INC | Scott Allen Schuster | — | (714) 463 4596 | HVAC | Anaheim · Orange County | — | — |
| Air Flowe LLC | Austin Roberts Flowe | — | (949) 879 0610 | HVAC | Westminster · Orange County | — | — |
| Air Max INC | Felorin Mirshahzadeh | — | (949) 468 9999 | HVAC | Laguna Niguel · Orange County | — | — |
| Air Max Jb Mechanical Heating And Cooling | Jesus Benitez | — | (714) 395 2509 | HVAC | Anaheim · Orange County | — | — |
| Air Max Oc | Afandi Adam | — | (714) 732 8333 | HVAC | Huntington Beach · Orange County | — | — |
| Air Mighty Refrigeration & Air Conditioning | Michael Phillip Rubio | — | (714) 204 8788 | HVAC | Yorba Linda · Orange County | — | — |
| Air Pro Heating And Air Conditioning | Lowell Steven Sproule | — | (562) 493 8516 | HVAC | Los Alamitos · Orange County | — | — |
| Air Revolution Heating And Cooling INC | Ramirez Arturo Gutierrez | — | (714) 290 0582 | HVAC | Fullerton · Orange County | — | — |
| Air Solutions | Air Solutions | — | (714) 863 3433 | HVAC | Tustin · Orange County | — | — |
| Air Supply Htg & A / C INC | Eddie Paredes Tavera | — | (714) 773 5865 | HVAC | Fullerton · Orange County | — | — |
| Air Technical Services INC | Jeremy Edward Southard | — | (714) 231 5486 | HVAC | Los Alamitos · Orange County | — | — |
| Air Temperature Solution | Air Temperature Solution | — | (949) 973 0209 | HVAC | Rancho Santa Margarita · Orange County | — | — |
| Air Treatment Corporation | Brian Lane Lawless | info@airtreatment.com | (909) 869 7975 | HVAC | Brea · Orange County | — | — |