| Aldin Dallos | Aldin Dallos | — | (925) 819 1757 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| Aleck Construction Company | Jay C Aleck | — | (415) 730 9069 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Alex Bowman | Alex Bowman | alex@alexbowman.com | (415) 374 5467 | Windows, patio, painters | Oakland · Alameda County | — | — |
| Alex Colt Construction | Alexander Endriss Colt | — | (510) 735 4707 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Alex Construction | Alexandros Athan Nikolaou | — | (510) 427 1642 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Alex Cordrey Construction INC | Alexander Lee Cordrey | — | (510) 497 1657 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Alex Electric | Heickenko Oleksandr | — | (415) 577 3019 | Electricians | Hayward · Alameda County | — | — |
| Alex Sanchez Construction | Sanchez Valadez Alejandro | — | (408) 390 1077 | GC, remodel, ADU | Newark · Alameda County | — | — |
| Alex Wong Construction | Kwang Chi Wong | — | (510) 542 7187 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Alfa & Omega Construction & Remodeling INC | Medina Ivan Espinoza | — | (408) 781 0049 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| Alfa Opportunity Holdings DBA Alfa Plumbing | Jorge Luis Alvarado | — | (510) 558 3494 | Other | Albany · Alameda County | — | — |
| Alfredo Electric | Alfredo Devera Acosta | — | (510) 434 6239 | Electricians | Alameda · Alameda County | — | — |
| Alfredo's Concrete INC | Alfredo Garcia Esquivez | — | (510) 489 3408 | Other | Union City · Alameda County | — | — |
| Algebra Probuild INC | Wegdan Abdullah Al Awdi | — | (415) 635 5585 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Alhorn/hooven A Design Build Collaborative LLC | Lyn Marie-Anne Alhorn | — | (510) 914 6240 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Ali Afrasiabi | Ali Afrasiabi | — | (415) 637 2460 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Ali Rostami | Ali Rostami | rostami.ali@gmail.com | (510) 459 8161 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Ali's Construction | Ali Rosan | — | (415) 205 9817 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Aliamus Construction | Dean Mathew Aliamus | — | (650) 575 8174 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| Align Furniture Services | Karen Patricia Micklewright | info@alignfurnitureservices.com | (510) 351 1300 | Other | San Leandro · Alameda County | — | — |
| Alix Build Solutions INC | Ferreira Juliander Alves | contact@alixbuildsolutions.com | (510) 689 9431 | GC, remodel, ADU | San Lorenzo · Alameda County | — | — |
| Alizoti INC | Alizoti Emiljano | — | (415) 341 6577 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| All About Air | All About Air | — | (510) 538 2247 | HVAC | Hayward · Alameda County | — | — |
| All About Windows | All About Windows | — | (510) 547 4087 | Other | Piedmont · Alameda County | — | — |
| All Above General Contractors INC | Jose Abraham Aranda Alvarez | — | (510) 688 4386 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| All Air Equipment - Installation Professionals | Derek Michel Caponigro | — | (925) 462 3883 | HVAC | Pleasanton · Alameda County | — | — |
| All American Painting Company | Alan Axel Mac Gregor | — | (925) 395 0224 | Windows, patio, painters | Castro Valley · Alameda County | — | — |
| All Around Construction | Steven Lee Reynolds | info@allaroundconstruction.com | (732) 280-6530 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| All Aspects | All Aspects | — | (510) 541 6557 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| All Bay Area Glass | All Bay Area Glass | — | (510) 553 1335 | Windows, patio, painters | Oakland · Alameda County | — | — |
| All Bay Contractors INC | George Ramirez Chapa | al@allbaycontractors.com | (650) 444-4485 | HVAC | Fremont · Alameda County | — | — |
| All Bay Garage Doors INC | Kevin Paul Chervatin | — | (510) 969 7167 | Other | San Leandro · Alameda County | — | — |
| All Bay Installation LLC | Alvarez Leobardo Mercado | — | (510) 753 3907 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| All Bay Plumbing Incorporated | Ezequiel Amaya | — | (650) 814 0241 | Other | Newark · Alameda County | — | — |
| All Cal Trades Builders INC | Hossein Joseph Garakani | — | (510) 714 0704 | GC, remodel, ADU | Alameda · Alameda County | — | — |
| All Clear Plumbing And Drain | Toby A Amido | — | (510) 397 2438 | Other | Hayward · Alameda County | — | — |
| All Color Painting | All Color Painting | — | (925) 447 9108 | Windows, patio, painters | Livermore · Alameda County | — | — |
| All Commercial Fire Protection INC | Daniel Stephan Deasy | — | (510) 898 8797 | Other | Castro Valley · Alameda County | — | — |
| All Environmental Co | Chong Uk Kim | — | (510) 427 3411 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| All Fixture Plumbing | All Fixture Plumbing | — | (510) 760 6181 | Other | Castro Valley · Alameda County | — | — |