| A1 Builds INC | Garcia Aaron Ramon | — | (510) 606 2398 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| A1 Gutierrez Construction | Gutierrez Medina Alfredo | — | (510) 576 9243 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| A1 Sun INC | Joel Benjamin Frangquist | — | (510) 526 5715 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| A2z Kitchen & Bath | Postiner Dror | — | (800) 476 9660 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Aa Premier Builder | Juan Jesus Mendoza | aapremierbuilder@gmail.com | (415) 515 3385 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Aa Quality Construction INC | Alex Atyai | — | (925) 216 1845 | GC, remodel, ADU | Dublin · Alameda County | — | — |
| Aaa Builders | Aaa Builders | — | (510) 259 8158 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Aaa Fire Protection Services | Brent Hathaway Patterson | — | (800) 543 5556 | Other | Union City · Alameda County | — | — |
| Aaa Plumbing & Remodeling INC | Jose Manuel Ramos | — | (510) 737 2376 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Aaaa Generator Services INC | Michael Bernard Chiasson | — | (888) 664 2436 | Electricians | Hayward · Alameda County | — | — |
| Aac Glass INC | Ali Missaghi | — | (510) 431 3303 | Windows, patio, painters | Hayward · Alameda County | — | — |
| Aall Fire Protection Services | Edward Raymond Gonsalves | — | (888) 988 0202 | Other | Livermore · Alameda County | — | — |
| Aarex Group | Amir Moayedi | — | (408) 775 4104 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Aaron Cruz Electric | Cruz Aaron | — | (415) 205 4440 | Electricians | Oakland · Alameda County | — | — |
| Aaron Lerner General Contractor | Aaron Lerner General Contractor | — | (650) 222 5833 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Aaron Murphy Electric | Aaron Eugene Murphy | — | (650) 704 8797 | Electricians | Hayward · Alameda County | — | — |
| Aarvaks Heating & Air Conditioning | Jason Alan Hanson | — | (510) 848 5010 | HVAC | Berkeley · Alameda County | — | — |
| Aashna Construction / Landscaping | Zahir Benush Razban | — | (510) 684 3354 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Ab Construction Co | Abdel Abraham Maradiaga Castillo | — | (510) 209 4318 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Abante Rooter And Plumbing INC | Fred Ramezan Heidarpour | — | (510) 534 1636 | Other | Emeryville · Alameda County | — | — |
| Abay Painting | Abay Painting | — | (510) 402 8477 | Windows, patio, painters | Fremont · Alameda County | — | — |
| Abayla Contracting Services INC | Tony Fernandes | — | (925) 820 2034 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| Abbott Improvements INC | Jason Prescott Abbott | — | (510) 517 6849 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Abc Dano Electrical Services | Daniel Stephen Mitchum | — | (510) 815 1070 | Electricians | Livermore · Alameda County | — | — |
| Abel Diaz Construction INC | Abel Pelayo Diaz | — | (510) 690 1219 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Abella Tile Stone | Abella Tile Stone | — | (510) 375 7913 | Other | Berkeley · Alameda County | — | — |
| Abercrombie Electric | Larry Del Abercrombie | — | (925) 339 0680 | Electricians | Livermore · Alameda County | — | — |
| Abg Painting | Elliot Trent Thompson | — | (424) 529 2625 | Windows, patio, painters | Oakland · Alameda County | — | — |
| Abia Property Management INC | James Robert Selover | — | (925) 580 6401 | Windows, patio, painters | Livermore · Alameda County | — | — |
| Abigail Energy Group LLC | Victor Manuel Munoz | — | (925) 397 4669 | Electricians | Livermore · Alameda County | — | — |
| Ability Maintenance INC | Jerry Gerard Hannah | — | (510) 455 7322 | GC, remodel, ADU | San Lorenzo · Alameda County | — | — |
| Abinesh's Electric | Nand Abinesh | — | (510) 331 5546 | Electricians | Hayward · Alameda County | — | — |
| Able Construction | Ravind Raj | — | (510) 825 5912 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Able To Plumbing And Rooter | Able To Plumbing And Rooter | — | (925) 606 0990 | Other | Livermore · Alameda County | — | — |
| Above 580 Painting | Above 580 Painting | — | (510) 575 1022 | Windows, patio, painters | San Leandro · Alameda County | — | — |
| Above All Plumbing INC | Ricky Gene Brown | — | (510) 475 6040 | Other | Newark · Alameda County | — | — |
| Above And Beyond Construction | Tammy Joy Long | — | (510) 232 4222 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Abram's Electric INC | Kenneth Perry Green | — | (510) 205 3623 | Electricians | Oakland · Alameda County | — | — |
| Abrams / Millikan & Associates | Millikan Richard | — | (510) 644 3002 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Abrew Repair & Construction | Kevin Michael Abrew | — | (925) 833 0128 | GC, remodel, ADU | Dublin · Alameda County | — | — |