| Bay One Construction & Remodeling | Simon Mandip Latchman | — | (510) 303 3680 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Bay Painting | Bay Painting | — | (510) 303 8901 | Windows, patio, painters | Oakland · Alameda County | — | — |
| Bay Plumbing | Bay Plumbing | — | (510) 860 2147 | Other | Berkeley · Alameda County | — | — |
| Bay Point Construction INC | Wing Look Michael Toy | — | (415) 928 9954 | GC, remodel, ADU | Alameda · Alameda County | — | — |
| Bay Restorators Corporation | Everardo Rodriguez | — | (510) 534 6647 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Bay Signs INC | Hanifa Bibi Gaphoor | — | (510) 278 4522 | Other | San Leandro · Alameda County | — | — |
| Bay Star Fire Protection Incorporated | Oscar Jeovany Escobar | — | (510) 377 4757 | Other | Hayward · Alameda County | — | — |
| Bay To Bay Wood Works And Carpentry INC | Aguilera Felipe Garcia | — | (510) 529 1652 | Other | Emeryville · Alameda County | — | — |
| Bay Valley Construction LLC | John Anthony Young | — | (925) 605 6228 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| Bay Valley Heating And Air Conditioning | Wayne Robert Siwik | — | (925) 336 0063 | HVAC | Livermore · Alameda County | — | — |
| Bay Valley Insulation INC | Guy Anthony Roth | g.roth@bayvalleyinsulation.com | (510) 791 5535 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Bay Villa Builders | Charles Anthony Villalobos | charlie@bayvillabuilders.com | (818) 451 7716 | GC, remodel, ADU | Newark · Alameda County | — | — |
| Bay Water Plumbing INC | Alvaro Rafael Avila | — | (510) 900 9888 | Other | Newark · Alameda County | — | — |
| Bay Wide Plumbing Heating And Air | Wayne Mathew Lopez | — | (510) 570 6770 | HVAC | San Leandro · Alameda County | — | — |
| Bay/coast Plumbing | Bay/coast Plumbing | — | (510) 919 8017 | Other | Alameda · Alameda County | — | — |
| Bayat Construction Co | Bayatmakou Siamak | — | (510) 697 2240 | Electricians | San Leandro · Alameda County | — | — |
| Baycore Builders LLC | Franklin Charles Diblasi | — | (510) 759 1150 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Bayhi Building INC | Ivan Jia-Jun Pan | — | (510) 207 6262 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Bayland Landscaping | Bayland Landscaping | — | (510) 882 1723 | Windows, patio, painters | Union City · Alameda County | — | — |
| Bayshield Roofing | Khanh Cong Tran | — | (510) 650 5818 | Other roofers | Union City · Alameda County | — | — |
| Bayside Builders Group INC | Eliram Eliran Susan | — | (510) 901 9972 | GC, remodel, ADU | Alameda · Alameda County | — | — |
| Bayside Interiors INC | Timothy Michael Hogan | impallari@gmail.com | (510) 438 9171 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Bayside Specialty Construction LLC | Jeffrey Mark Saulovich | — | (510) 910 2091 | GC, remodel, ADU | Alameda · Alameda County | — | — |
| Baytech Communications INC | Peric Miro | — | (510) 760 6646 | Other | San Leandro · Alameda County | — | — |
| Bayvalley Mechanical INC | Anthony Joel Cedillo | office.dispatch@bayvalleymechanical.com | (510) 557 8643 | Other | Union City · Alameda County | — | — |
| Bayview Contracting & Remodeling INC | Vidal Isabel Diaz | — | (510) 681 9614 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Bayview Demolition Services INC | Lance Thomas Cleveland | — | (510) 542 6181 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Bayview Environmental Services INC | Lance Thomas Cleveland | — | (510) 542 6181 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Bayview Fire Protection INC | Edgar Salvador Hernandez Garcia | ehfire@outlook.com | (510) 432 2612 | Other | San Leandro · Alameda County | — | — |
| Bayview Industrial Services INC | Lance Thomas Cleveland | — | (510) 562 6181 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Bayview Plumbing | Bayview Plumbing | — | (510) 551 7900 | Other | San Leandro · Alameda County | — | — |
| Baywood Building & Design INC | Robert Patrick Malone | — | (510) 595 4231 | GC, remodel, ADU | Emeryville · Alameda County | — | — |
| Bayzenith General Construction INC | Pascual Diaz | — | (510) 760 1908 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Bbi Construction | Kay Ka-Kei Chan | bids@bbiconstruction.com | (510) 286 8200 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Bbi-bjork Jv | Construction Bbi | — | (510) 286 8200 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Bc Metal Fabrication | Bc Metal Fabrication | — | (341) 205 1964 | Other | Oakland · Alameda County | — | — |
| Bcec-breslin Construction & Engineering Co | Anthony Joseph Breslin | — | (650) 823 0928 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Bcm General Construction INC | Santiago Mario Cruz | — | (510) 447 9713 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Bd Construction | Bejenariu Daniel | — | (510) 967 9889 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Bear Construction INC | Miguel Angel Lopez | — | (510) 736 6499 | Other | Hayward · Alameda County | — | — |