| B C Restaurant Equipment Installations LLC | Sonny Calcagno Davis | — | (707) 570 1200 | Other | Santa Rosa · Sonoma County | — | — |
| B C S Electric | Peter Duncan Gordon | — | (707) 364 4066 | Electricians | Petaluma · Sonoma County | — | — |
| B D Compton Construction INC DBA Compton Construction Company | Brian Dennis Compton | — | (707) 481 7680 | GC, remodel, ADU | Windsor · Sonoma County | — | — |
| B D Insulation Co | David Bryan Cox | admin@bdinsulation.com.au | (707) 206 1792 | Other | Santa Rosa · Sonoma County | — | — |
| B D S | B D S | — | (707) 373 2021 | Electricians | Sonoma · Sonoma County | — | — |
| B E Bird Landscape | B E Bird Landscape | — | (707) 578 7739 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| B H Building | B H Building | — | (707) 291 7686 | GC, remodel, ADU | Sebastopol · Sonoma County | — | — |
| B H Tile And Stone | B H Tile And Stone | — | (415) 299 4917 | Other | Rohnert Park · Sonoma County | — | — |
| B Henry's Quality Electric INC | William Thomas Jr Henry | bhqelectric@comcast.net | (707) 774 2112 | Electricians | Petaluma · Sonoma County | — | — |
| B K M Drywall | B K M Drywall | — | (707) 332 5427 | Other | Santa Rosa · Sonoma County | — | — |
| B K W Concrete INC | William Eric Rietman | — | (707) 836 1982 | Other | Santa Rosa · Sonoma County | — | — |
| B M K Construction | Ronald Carl Piethe | — | (408) 623 2636 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| B W Builder | William Robert Wallace | — | (707) 595 8912 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| B White Floors | B White Floors | — | (707) 695 8783 | Other | Santa Rosa · Sonoma County | — | — |
| B's Building Service | Robert Louis Brouwers | — | (707) 887 2249 | GC, remodel, ADU | Forestville · Sonoma County | — | — |
| Babson And Sons Construction INC | Bob Glyn Jr Babson | — | (707) 540 0674 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Baer General Construction INC | Scott James Baer | — | (707) 975 7839 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Baggenstos & Associates INC | Bruce M Baggenstos | — | (707) 576 7774 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |
| Baggett Building Enterprise | Baggett Building Enterprise | — | (707) 495 3477 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Bahram Navi | Bahram Navi | — | (408) 975 0836 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Baicon Enterprise INC | Neil Wayne Bailey | — | (717) 806 2290 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Baier Heating And Air Conditioning INC | Chad William Baier | — | (707) 890 5330 | HVAC | Rohnert Park · Sonoma County | — | — |
| Bailey Smith Electric | Bailey Dale Smith | — | (415) 732 9324 | Electricians | Sonoma · Sonoma County | — | — |
| Baker Pre Construction Co | Alysson Joan Baker | — | (707) 799-3102 | GC, remodel, ADU | Sebastopol · Sonoma County | — | — |
| Baldry Brothers Drilling | Jeffery Samuel Sexton | — | (707) 974 3308 | Other | Windsor · Sonoma County | — | — |
| Balestrini Floors INC | Mario Delaney Ray Balestrini | — | (707) 787 0546 | Other | Petaluma · Sonoma County | — | — |
| Balistreri Commercial Pool Service And Repair | Vincente Gianni Balistreri | — | (707) 338 7561 | Pool | Petaluma · Sonoma County | — | — |
| Balistreri Pool Service & Repair | John Zolezzi Balistreri | — | (707) 799 9218 | Pool | Petaluma · Sonoma County | — | — |
| Ballatore Enterprises | Spirito Jean Ballatore | — | (707) 484 8233 | GC, remodel, ADU | Valley Ford · Sonoma County | — | — |
| Ballinger Restaurant Equipment INC | Larry Moore Ballinger | — | (707) 291 0877 | Other | Santa Rosa · Sonoma County | — | — |
| Baltic Construction | Gudauskas Rimvydas | — | (707) 481 6778 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Bannside Construction INC | Patrick Declan Wilson | — | (415) 678 6978 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| Bantam Electric | Jason Carl Martinelli | — | (707) 303 0204 | Electricians | Santa Rosa · Sonoma County | — | — |
| Barajas Tile Stone | Barajas Tile Stone | binb7880@gmail.com | (707) 843 8005 | Other | Santa Rosa · Sonoma County | — | — |
| Barba Plumbing INC | Pedro Gomez Barba | — | (707) 921 8698 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Barbieri Electric | Ryan Stephen Barbieri | barbierielectric@gmail.com | (707) 494 2276 | Electricians | Cotati · Sonoma County | — | — |
| Barbosa Custom Concrete | Barbosa Custom Concrete | — | (707) 322 5866 | Other | Santa Rosa · Sonoma County | — | — |
| Barboza Painting | Barboza Painting | — | (707) 934 5658 | Windows, patio, painters | Sonoma · Sonoma County | — | — |
| Barcelo Floors | Barcelo Floors | — | (707) 495 7059 | Other | Santa Rosa · Sonoma County | — | — |
| Barefoot Development Earthworks Division | Barefoot Development Earthworks Division | — | (707) 621 3668 | Other | Sebastopol · Sonoma County | — | — |