| Alfred Herzog | Alfred Herzog | — | (714) 813 4756 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Alfred Lara | Alfred Lara | — | (951) 660 8829 | Electricians | Laguna Hills · Orange County | — | — |
| Alfred Villagrana Jr | Alfred Villagrana Jr | — | (562) 451 3097 | GC, remodel, ADU | La Habra · Orange County | — | — |
| Algene Robinson | Algene Robinson | — | (714) 504 6497 | Electricians | Orange · Orange County | — | — |
| Algorri Pools | Algorri Pools | — | (562) 305 9788 | Pool | Buena Park · Orange County | — | — |
| Alh Security INC | Yuval Harpaz | — | (800) 416 8955 | Alarm and generators | Lake Forest · Orange County | — | — |
| Ali Altaha | Ali Altaha | — | (510) 812 5210 | Other | Mission Viejo · Orange County | — | — |
| Ali Ghomizadeh | Ali Ghomizadeh | — | (949) 292 2701 | GC, remodel, ADU | Laguna Hills · Orange County | — | — |
| Ali Kalantarifiroozabad | Ali Kalantarifiroozabad | — | (949) 910 5853 | GC, remodel, ADU | Newport Coast · Orange County | — | — |
| Ali Mahmoudi Pousti | Ali Mahmoudi Pousti | — | (949) 449 6710 | GC, remodel, ADU | Mission Viejo · Orange County | — | — |
| Ali Mohammadi | Ali Mohammadi | — | (949) 333 9322 | Other | Lake Forest · Orange County | — | — |
| Ali Pourdastan | Ali Pourdastan | — | (949) 233 2862 | GC, remodel, ADU | San Clemente · Orange County | — | — |
| Ali Vallysedigh | Ali Vallysedigh | — | (949) 444 1034 | GC, remodel, ADU | Trabuco Canyon · Orange County | — | — |
| Alicia Air Conditioning & Heating INC | Bryan Oscar Perez | — | (949) 770 2495 | HVAC | Lake Forest · Orange County | — | — |
| Align Installations | Farhad Moravej Hamadani | — | (949) 791 9020 | GC, remodel, ADU | Newport Beach · Orange County | — | — |
| Aligned Glass Tech LLC | James Rolf Cappelmann | — | (619) 565 1411 | Windows, patio, painters | Mission Viejo · Orange County | — | — |
| Alignment Renovations | Alignment Renovations | — | (714) 631 4714 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| Alireza Poormohammad Dargah | Alireza Poormohammad Dargah | — | (310) 991 2311 | GC, remodel, ADU | Irvine · Orange County | — | — |
| Alireza Sabouriazad | Alireza Sabouriazad | — | (760) 298 9470 | GC, remodel, ADU | Rancho Santa Margarita · Orange County | — | — |
| Alireza Shahinnejad | Alireza Shahinnejad | — | (805) 320 3309 | GC, remodel, ADU | Rancho Santa Margarita · Orange County | — | — |
| Alireza Yazdanshenas | Alireza Yazdanshenas | — | (949) 279 0027 | GC, remodel, ADU | San Juan Capistrano · Orange County | — | — |
| Aliso Air INC | Christopher Howard Loftus | — | (949) 589 2021 | HVAC | Rancho Santa Margarita · Orange County | — | — |
| Aliso Concrete Corp | Popoca Francisco Nicolas | — | (949) 446 7170 | Other | Aliso Viejo · Orange County | — | — |
| Aliso Electric INC | Paul George Grey | — | (949) 598 0359 | Electricians | Laguna Hills · Orange County | — | — |
| Aliso Viejo Tree Service | Aliso Viejo Tree Service | — | (949) 649-7346 | Tree | Aliso Viejo · Orange County | — | — |
| Alita Construction INC | Zhouqing Ye | info@alitaconstruction.com | (949) 439 3863 | Electricians | Irvine · Orange County | — | — |
| Alkay Enterprises INC | Ronald Allison Wyman | — | (714) 662 2300 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| Alkm | Andres Guzman | — | (714) 235 5705 | HVAC | Garden Grove · Orange County | — | — |
| All - Star Communications | All - Star Communications | — | (714) 721 0469 | Other | Tustin · Orange County | — | — |
| All About Construction | Robert Anthony Sanchez | — | (714) 719 4257 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| All About Patio Covers | All About Patio Covers | — | (714) 306 4920 | Other | Anaheim · Orange County | — | — |
| All Access Doors INC | Villarreal Enoc | — | (714) 290 7628 | Other | Fullerton · Orange County | — | — |
| All Advance Construction INC | Vega Alberto Dominguez | — | (949) 933 8624 | GC, remodel, ADU | Santa Ana · Orange County | — | — |
| All Air Engineering Co | Kim Kevin | — | (714) 349 7008 | HVAC | Cypress · Orange County | — | — |
| All American Abatement INC | Gary Allen Eppens | — | (714) 282 0300 | GC, remodel, ADU | Yorba Linda · Orange County | — | — |
| All American Acoustics INC DBA Facility Service Construction | Dacy Jr Holt | — | (714) 898 4180 | GC, remodel, ADU | Garden Grove · Orange County | — | — |
| All American Awnings | All American Awnings | — | (714) 943 4591 | Other | Santa Ana · Orange County | — | — |
| All American Design And Construction Company | Robert Lynne Chenowith | — | (714) 865 3151 | GC, remodel, ADU | Orange · Orange County | — | — |
| All American Door INC | Greg Adam Brittain | — | (714) 680 8999 | GC, remodel, ADU | Fullerton · Orange County | — | — |
| All American Lock Corporation | Ruth Evelyn Beardsley | — | (714) 202 8009 | Windows, patio, painters | Huntington Beach · Orange County | — | — |