| American Superior Painting INC | Mendoza Felipe Arriaga | — | (714) 493 9863 | Windows, patio, painters | Anaheim · Orange County | — | — |
| American Supreme Roofing | Daniel Hermilo Jr Vazquez | info@roofasr.com | (714) 973 0000 | Other roofers | Santa Ana · Orange County | — | — |
| American Swimming Pool | American Swimming Pool | — | (714) 388 4324 | Pool | Anaheim · Orange County | — | — |
| American System Integrators | Ronia Bernardin Panelo Noval | — | (949) 800 6834 | Electricians | Mission Viejo · Orange County | — | — |
| American Tile & Stone Contractor | American Tile & Stone Contractor | — | (714) 728 0002 | GC, remodel, ADU | Huntington Beach · Orange County | — | — |
| American Virtual Monitoring INC | Alex Xavier Solorio | — | (888) 354 7722 | Other | Lake Forest · Orange County | — | — |
| American Vision Windows | American Vision Windows | — | (714) 551-9302 | Windows, patio, painters | Tustin · Orange County | — | — |
| American Way Pipeline INC | Amador Gomez | — | (714) 519 4415 | Other | Fullerton · Orange County | — | — |
| American West Services | Glenn Leroy Wennen | — | (949) 644 6425 | HVAC | Newport Beach · Orange County | — | — |
| American West Tile | Galindo Ricardo Zapata | — | (213) 807 5159 | Other | Garden Grove · Orange County | — | — |
| American Window Covering INC | Lisa Renee Wozab | — | (714) 879 3880 | Other | Fullerton · Orange County | — | — |
| American Window Film | Matthew Ronald Darienzo | — | (949) 825 7940 | Other | Laguna Hills · Orange County | — | — |
| American Wireless Construction INC | Justin James Zanoni | — | (714) 849 1738 | Electricians | Stanton · Orange County | — | — |
| Americo Builders LLC | Christopher Richard Kent | — | (714) 430 7730 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Americool Heating And Air | Americool Heating And Air | — | (714) 356 8826 | HVAC | Placentia · Orange County | — | — |
| Amerikan Interstate Garage Door Company | Erik Todd Smallwood | — | (714) 454 5161 | Other | Orange · Orange County | — | — |
| Ameriko General Construction & Remodeling | America A Jung | — | (714) 714 6000 | GC, remodel, ADU | Fullerton · Orange County | — | — |
| Ameriproj INC | Matt Rikkaei | — | (714) 803 4233 | GC, remodel, ADU | Mission Viejo · Orange County | — | — |
| Ameriside | Arash Ghahfarokhi Esmaili | — | (949) 215 4050 | GC, remodel, ADU | Lake Forest · Orange County | — | — |
| Amerman Wood Flooring | Amerman Wood Flooring | — | (949) 300 7642 | Other | Lake Forest · Orange County | — | — |
| Amezcua Construction | Amezcua Constantino Juan | — | (714) 981 8360 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Amf Construction | Albert Michael Fuentes | — | (714) 209 1242 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Amgen Builders | Andre Hurst | — | (949) 542 8777 | GC, remodel, ADU | Capistrano Beach · Orange County | — | — |
| Amida Resources INC | Jerry Alan Roteman | — | (714) 255 2944 | Electricians | Yorba Linda · Orange County | — | — |
| Amiel Construction | Carlos Enrique Amiel | — | (562) 972 0484 | GC, remodel, ADU | Los Alamitos · Orange County | — | — |
| Amigo Restoration | Amigo Restoration | — | (949) 573 4074 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| Amin Nazarinia | Amin Nazarinia | — | (424) 279 2838 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Amir Reza Yazdanshenas | Amir Reza Yazdanshenas | — | (949) 306 6414 | Other | San Juan Capistrano · Orange County | — | — |
| Amir's Construction Design | Amir Mehdi Eftekhari | — | (657) 256 1211 | GC, remodel, ADU | Stanton · Orange County | — | — |
| Amko Contractors INC | Jun Suk Seo | — | (714) 719 5312 | HVAC | Anaheim · Orange County | — | — |
| Amko Development INC | Dan Sehyoung| Lee Se Hyoung Lee | — | (714) 524 7797 | GC, remodel, ADU | Placentia · Orange County | — | — |
| Amogen | William Donald Brown | — | (714) 745 7375 | HVAC | Yorba Linda · Orange County | — | — |
| Amort Construction INC | Steven Joseph Amort | bids@amortconstruction.com | (714) 998 2401 | GC, remodel, ADU | Orange · Orange County | — | — |
| Amp Builder | Amp Builder | — | (714) 356 7282 | GC, remodel, ADU | Placentia · Orange County | — | — |
| Amp Construction | Andrew Michael Potter | — | (949) 514 1006 | GC, remodel, ADU | Newport Beach · Orange County | — | — |
| Amp Mechanical INC | Gary Schneider | — | (714) 241 1769 | HVAC | Costa Mesa · Orange County | — | — |
| Amp't Electric INC | Michael Daniel Castle | — | (714) 658 1143 | Electricians | Anaheim · Orange County | — | — |
| Ampco North INC | Andrew Michael Pennor | — | (949) 412 8071 | GC, remodel, ADU | Rancho Santa Margarita · Orange County | — | — |
| Ampd Electrical | Ulises Delaluz Trujillo | info@ampd-electrical.com | (657) 289-7012 | Electricians | Santa Ana · Orange County | — | — |
| Amped Electric INC | Alvaro Alvarado | — | (714) 900 1021 | Electricians | Anaheim · Orange County | — | — |