| Alpha Dynamic Group INC DBA Alpha Dynamic Builders | Eligio Antonio Morales | — | (408) 480 8328 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| Alpha Fire Suppression Systems INC | Jack Alan Gale | — | (707) 527 6407 | Other | Santa Rosa · Sonoma County | — | — |
| Alpha Omega Builders | Alpha Omega Builders | — | (707) 974 2048 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Alpha Trenchless | Francisco Javier Zaragoza | — | (415) 377 6939 | Other | Petaluma · Sonoma County | — | — |
| Alphabet Plumbing INC | Stephen John Consiglio-helgeson | — | (707) 322 5759 | Other | Santa Rosa · Sonoma County | — | — |
| Alpine Construction | Jason David Severn | — | (707) 477 7655 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| Alpine Electric | Matthew James Larsen | — | (707) 291 6890 | Electricians | Santa Rosa · Sonoma County | — | — |
| Alpine Roofing Company | Marco John Iii Mimmo | — | (707) 823 3126 | Other roofers | Sebastopol · Sonoma County | — | — |
| Alta Vista Construction | Roger Allen Moore | — | (707) 334 3007 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Altamirano Appliance Refrigeration INC | Ramiro Eulises Altamirano Gopar | — | (707) 623 5164 | HVAC | Rohnert Park · Sonoma County | — | — |
| Alvarado Brothers Construction INC | Alvarado-mendoza Ismael | — | (707) 799 1439 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| Alvarado Homes Construction INC | Eleazar Alvarado | — | (707) 483 7794 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Alvarado Plumbing | Alvarado Plumbing | — | (707) 484 1513 | Other | Santa Rosa · Sonoma County | — | — |
| Alvarez Framing | Alvarez Framing | hello@rfuenzalida.com | (707) 494 4689 | Other | Santa Rosa · Sonoma County | — | — |
| Alvarez Landscape | Alvarez Landscape | — | (707) 293 0482 | Windows, patio, painters | Rohnert Park · Sonoma County | — | — |
| Alvarez Landscaping INC | Raphael| Alvare Z Rafael Alvarez | — | (707) 431 0295 | Windows, patio, painters | Healdsburg · Sonoma County | — | — |
| Alver Plumbing | Alver Plumbing | — | (707) 889 3747 | Other | Rohnert Park · Sonoma County | — | — |
| Alves Construction | Marc Anthony Alves | — | (707) 310 5656 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Alvis Plumbing | Alvis Plumbing | — | (707) 697 8794 | Other | Rohnert Park · Sonoma County | — | — |
| Am Parra Drywall | Am Parra Drywall | — | (707) 732 3728 | Other | Santa Rosa · Sonoma County | — | — |
| Am Tinting | Am Tinting | alex@amtinting.com | (707) 806 9932 | Other | Petaluma · Sonoma County | — | — |
| Ama Diversfied Construction Group | Aaron Marion Arellanes | — | (707) 595 6033 | Other | Petaluma · Sonoma County | — | — |
| Amato Masonry INC | Mark Eugene Amato | — | (707) 579 1175 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Ambiance Painting And Decorating | Ambiance Painting And Decorating | — | (707) 887 1499 | Windows, patio, painters | Forestville · Sonoma County | — | — |
| America's Pool Service Company | Christopher Scott Mazzanti | — | (707) 237 5353 | Pool | Windsor · Sonoma County | — | — |
| American Builders | American Builders | — | (415) 559 6759 | HVAC | Sonoma · Sonoma County | — | — |
| American Canvas Products | Kathleen Hannon Mc Gill | interested@domainmarket.com | (415) 826 7515 | Other | Petaluma · Sonoma County | — | — |
| American Craftsman Countertops | American Craftsman Countertops | — | (707) 576 0104 | Other | Santa Rosa · Sonoma County | — | — |
| American Design & Build INC | Gene Lawrence Tygielski | — | (415) 601 9104 | GC, remodel, ADU | Rio Nido · Sonoma County | — | — |
| American Drywall INC | Robert James Becerra | interested@domainmarket.com | (707) 537 8100 | Other | Santa Rosa · Sonoma County | — | — |
| American Heating & Air LLC | Anguiano Ricardo Mora | — | (707) 807 4822 | HVAC | Santa Rosa · Sonoma County | — | — |
| American Made Building INC | Robert Thomas Gibson | — | (707) 507 3700 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| American Quality Plumbing | American Quality Plumbing | — | (707) 819 7318 | Other | Santa Rosa · Sonoma County | — | — |
| American Radiant & Water Heating INC | Brendan Keith Dunbar | — | (707) 331 2199 | HVAC | Windsor · Sonoma County | — | — |
| American Tank Co INC | Mark David Luzaich | — | (707) 535 1401 | Other | Windsor · Sonoma County | — | — |
| American Video Systems INC | Kenneth Daniel White | — | (707) 542 2410 | Other | Santa Rosa · Sonoma County | — | — |
| American Water Treatment LLC | Colton Chapin Williams | — | (707) 823 4685 | Other | Sebastopol · Sonoma County | — | — |
| American Window And Door Systems INC DBA American Window Systems | Eddy August Deniz | — | (707) 258 0880 | Windows, patio, painters | Rohnert Park · Sonoma County | — | — |
| Amg Engineering | Amg Engineering | — | (707) 322 1193 | Other | Windsor · Sonoma County | — | — |
| Amormino & Pucci Painting | Philip Salvatore Amormino | — | (707) 227 6866 | Windows, patio, painters | Sonoma · Sonoma County | — | — |