| Scott Woodson Painting | Scott Woodson Painting | — | (707) 477 8860 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |
| Scribe Line INC | Jesse Sparre Swift | — | (707) 326 5347 | Other | Cotati · Sonoma County | — | — |
| Scuderi Builders INC | James Vincent Scuderi | — | (707) 953 0284 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Sculptural Gates LLC | Kenneth William Martini | sales@sculpturalgates.com | (707) 938 1127 | Electricians | Sonoma · Sonoma County | — | — |
| Sda Building | Sda Building | — | (707) 483 0286 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Sealund Construction | Brent Edward Sealund | — | (707) 304 0318 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Sean Bradford Construction | Sean Lee Bradford | — | (707) 291 6128 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Sean Dunn | Sean Dunn | — | (707) 953 8338 | GC, remodel, ADU | Sonoma · Sonoma County | — | — |
| Sean Hensley Plumbing Company | Sean Richard Hensley | — | (707) 525 9594 | Other | Santa Rosa · Sonoma County | — | — |
| Sean Mcwhirr Construction | Sean Peter Mc Whirr | — | (415) 726 7685 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| Seann Xenja | Seann Xenja | — | (707) 249 2873 | GC, remodel, ADU | Graton · Sonoma County | — | — |
| Seaside Landscapes Corp | Guion Brooks Mascolo | — | (707) 875 2470 | Windows, patio, painters | Duncans Mills · Sonoma County | — | — |
| Seaview / Ridge Construction | Construction Ridge | — | (707) 847 3344 | GC, remodel, ADU | Cazadero · Sonoma County | — | — |
| Seaview Construction | Dennis James Meredith | — | (707) 847 3332 | GC, remodel, ADU | Cazadero · Sonoma County | — | — |
| Seaview Land Restoration | Seaview Land Restoration | — | (707) 338 9818 | Restoration | Cazadero · Sonoma County | — | — |
| Seaview Tree Service | Jared Matthew Dupret | — | (707) 360 5834 | Tree | Forestville · Sonoma County | — | — |
| Sebastian Johnson | Sebastian Johnson | — | (213) 265 5010 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |
| Sebastopol Construction Services INC DBA L J Construction | Leeroy Joseph Sr Ress | — | (707) 823 0247 | Windows, patio, painters | Sebastopol · Sonoma County | — | — |
| Sebastopol Pool Service | Donald Howard Reece | — | (707) 823 7665 | Pool | Sebastopol · Sonoma County | — | — |
| Second Generation Roofing INC | Dale Edwin Daniels | — | (707) 765 8512 | Other roofers | Sebastopol · Sonoma County | — | — |
| Second Nature Tree Service | Graham Marcus Charles | — | (707) 227 2303 | Tree | Sonoma · Sonoma County | — | — |
| Select Cedar Sidewall Co | Dennis James Jagdfeld | — | (707) 295 6828 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |
| Sentient Landscape INC | Geoff Douglas Hall | — | (707) 829 3655 | Windows, patio, painters | Sebastopol · Sonoma County | — | — |
| Sequoia Computer | Sequoia Computer | info@sequoiacomputer.com | (707) 894 3900 | Other | Fulton · Sonoma County | — | — |
| Sequoia Tile & Stone | Sequoia Tile & Stone | — | (707) 548 3282 | Other | Santa Rosa · Sonoma County | — | — |
| Sergio's Masonry | Sergio's Masonry | — | (707) 292 4290 | Other | Rohnert Park · Sonoma County | — | — |
| Serrano Fire Protection Systems | Serrano Fire Protection Systems | — | (415) 724 3865 | Other | Petaluma · Sonoma County | — | — |
| Serres Corporation | John Pierre Serres | serres@serres.com | (707) 996 6776 | Other | Sonoma · Sonoma County | — | — |
| Serva Construction | Donald Patrick Serva | — | (707) 494 4027 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Servico Building Maintenance Company INC | Gary Anthony D'acquisto | — | (707) 935 1224 | Other | Glen Ellen · Sonoma County | — | — |
| Servpro Of Petaluma & Rohnert Park | Jenny Marlys Villena | — | (707) 665 0822 | GC, remodel, ADU | Cotati · Sonoma County | — | — |
| Sessi Solutions | Sessi Solutions | mlsessi@sessisolutions.com | (707) 974 9641 | Electricians | Penngrove · Sonoma County | — | — |
| Setanta Engineering | Setanta Engineering | — | (415) 298 4537 | Other | Petaluma · Sonoma County | — | — |
| Seth Alan Painting | Seth Alan Painting | — | (707) 813 0709 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |
| Setting The Standard Construction INC | William Tom Iv Cornwell | — | (707) 732 3647 | Other | Petaluma · Sonoma County | — | — |
| Severson Heating & Cooling | Severson Heating & Cooling | — | (707) 938 3929 | HVAC | Sonoma · Sonoma County | — | — |
| Sewer Line Survey | Sewer Line Survey | — | (707) 620 3955 | Other | Santa Rosa · Sonoma County | — | — |
| Sgc Builders INC | Vicente Salinas | — | (415) 827 1758 | GC, remodel, ADU | Rohnert Park · Sonoma County | — | — |
| Sh Siteworks | Silva Huey Jose | — | (707) 326 8067 | Other | Santa Rosa · Sonoma County | — | — |
| Shade Shop | Derich Ament Marsh | info@shadeshop.com | (877) 415 4158 | Other | Sonoma · Sonoma County | — | — |