| Blanchard Construction Incorporated | Richard James Blanchard | — | (707) 528 3989 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Blanco Painting INC | Justus Thomas Blanco | — | (707) 291 6848 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |
| Blank Custom Tile | Blank Custom Tile | — | (707) 480 0582 | Other | Santa Rosa · Sonoma County | — | — |
| Blasi Construction | Michael Todd Blasi | — | (707) 592 0509 | GC, remodel, ADU | Cloverdale · Sonoma County | — | — |
| Blaze Heating & Air Conditioning | Blaze Heating & Air Conditioning | — | (707) 396 7835 | HVAC | Santa Rosa · Sonoma County | — | — |
| Blazer Plumbing | Blazer Plumbing | — | (707) 704 7152 | Other | Rohnert Park · Sonoma County | — | — |
| Blinds Up Installation And Repair | Blinds Up Installation And Repair | — | (707) 483 1588 | Other | Santa Rosa · Sonoma County | — | — |
| Bludog Rooter & Plumbing Co | Gareth Adams | — | (707) 492 9656 | Other | Santa Rosa · Sonoma County | — | — |
| Blue Arc Electric | Richard Frank Wagner | info@bluearcelectric.com | (707) 331 3579 | Electricians | Santa Rosa · Sonoma County | — | — |
| Blue Barn Arts INC | Otis Gallagher | — | (707) 889 4986 | GC, remodel, ADU | Healdsburg · Sonoma County | — | — |
| Blue Collar Comfort INC | Rick Anthony Cordova | — | (707) 483 2883 | HVAC | Santa Rosa · Sonoma County | — | — |
| Blue Cypress Landscaping LLC | Mendoza Alvaro Martinez | — | (415) 720 1729 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |
| Blue Line Builder | Blue Line Builder | — | (707) 696 4029 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| Blue Line Interiors INC | Ala Muhamad Abual Halaweh | — | (707) 236 5343 | GC, remodel, ADU | Rohnert Park · Sonoma County | — | — |
| Blue Line Plumbing 1 INC | Jose Luis Rojas Sanchez | — | (707) 596 1408 | Other | Santa Rosa · Sonoma County | — | — |
| Blue Moon Builders INC | Loren R Carnevale | — | (707) 490 6642 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| Blue Oak Heating & Cooling INC | Somchit Khoupradit | — | (707) 582 1166 | HVAC | Santa Rosa · Sonoma County | — | — |
| Blue Oak Landscape Contractor INC | Anaya Macario Bedoy | — | (707) 758 5341 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |
| Blue Oak Low Voltage Systems | Emmet Maxwell Stanton | — | (408) 580 4691 | Other | Sebastopol · Sonoma County | — | — |
| Blue Revolution INC | Peter Kawaoka Hansen | team@bluerevolution.com | (707) 981 7025 | Pool | Petaluma · Sonoma County | — | — |
| Blue Sky Electric | Cristian Alejandro Quintana | — | (707) 331 0994 | Electricians | Santa Rosa · Sonoma County | — | — |
| Blue Star Gas Associates | Sidney Willem Grift | — | (707) 573 3130 | Electricians | Santa Rosa · Sonoma County | — | — |
| Blueprint Builders | Gregory John Hannan | hello@blueprintbuilders.com | (707) 595 4040 | GC, remodel, ADU | Graton · Sonoma County | — | — |
| Bluewater Builders INC | Gary Roger Shuman | — | (818) 437 4885 | GC, remodel, ADU | Santa Rosa Valley · Sonoma County | — | — |
| Bob Davis Construction | Robert Weldon Davis | — | (707) 322 7772 | Electricians | Santa Rosa · Sonoma County | — | — |
| Bob Etchell Plumbing & Heating | Bob Etchell Plumbing & Heating | — | (707) 888 2884 | HVAC | Healdsburg · Sonoma County | — | — |
| Bob Hight | Bob Hight | — | (707) 548 9200 | GC, remodel, ADU | Sebastopol · Sonoma County | — | — |
| Bob Murnane Carpets INC | Robert Patrick Murnane | — | (707) 543 8099 | Other | Santa Rosa · Sonoma County | — | — |
| Bob Saling Masonry | Bob Saling Masonry | info@bobsalingmasonry.com | (707) 523 1523 | Other | Santa Rosa · Sonoma County | — | — |
| Bob Schneider Landscaping | Bob Schneider Landscaping | — | (818) 426 4929 | Windows, patio, painters | Cotati · Sonoma County | — | — |
| Bob Woods Remodeling | Bob Woods Remodeling | — | (707) 871 9005 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Bob's Underground Septic | Bob's Underground Septic | bobsunderground@gmail.com | (707) 843 6944 | Other | Santa Rosa · Sonoma County | — | — |
| Boden Plumbing INC | Terrence Joseph Boden | info@bodenplumbing.com | (707) 996 8683 | HVAC | Sonoma · Sonoma County | — | — |
| Bogart Construction | Delmont Locke Bogart | — | (707) 338 3422 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| Bohan & Canelis General Engineering INC | Homer Peter Canelis | — | (707) 632 5708 | Other | Cazadero · Sonoma County | — | — |
| Bohan Construction INC | Paul James Bohan | — | (707) 849 9655 | GC, remodel, ADU | Sebastopol · Sonoma County | — | — |
| Boldt Electric Company | David Brian Boldt | boldtelectric@comcast.net | (707) 996 7224 | Electricians | Sonoma · Sonoma County | — | — |
| Bolt Down The Bay Area | Sean Kyler Warner | — | (707) 477 3347 | GC, remodel, ADU | Sebastopol · Sonoma County | — | — |
| Boltz Electric Contractors INC | Mel Francis Harold | — | (707) 975 7008 | Electricians | Santa Rosa · Sonoma County | — | — |
| Bon Terra Landscapes Construction | Isaac Israel Hernandez Arreola | — | (415) 755 0728 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |