| Ryan J & Kristi M Mcgunagle INC | Ryan Joseph Mc Gunagle | — | (707) 762 7900 | Other | Petaluma · Sonoma County | — | — |
| Ryan M. Wilbur | Ryan M. Wilbur | — | (518) 365 4011 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| Rydr Construction LLC | Rimvydas Gudauskas | contact@rydrconstruction.com | (707) 481 6778 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| S & K Builders | S & K Builders | — | (707) 974 5981 | GC, remodel, ADU | Windsor · Sonoma County | — | — |
| S & S Concrete | S & S Concrete | — | (707) 623 0828 | GC, remodel, ADU | Rohnert Park · Sonoma County | — | — |
| S & S Landscaping | S & S Landscaping | — | (707) 975 0320 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |
| S And S Construction INC | Kirk Rudolf Seidler | — | (707) 800 7077 | GC, remodel, ADU | Sebastopol · Sonoma County | — | — |
| S B C Electric | Salvatore Jerry Cimino | — | (707) 695 5135 | Electricians | Santa Rosa · Sonoma County | — | — |
| S B Drywall | S B Drywall | — | (707) 953 5179 | Other | Santa Rosa · Sonoma County | — | — |
| S B G C INC | Shawn Justin Brown | — | (707) 495 5969 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| S B S | Richard Nick Stanley | — | (707) 410 7852 | Other | Rohnert Park · Sonoma County | — | — |
| S D Landscaping | S D Landscaping | — | (707) 332 8975 | Windows, patio, painters | Rohnert Park · Sonoma County | — | — |
| S F Plumbing Services | Thomas Fredrick Gomes | — | (720) 270 9870 | Other | Santa Rosa · Sonoma County | — | — |
| S G Construction | Steffen Charles Gundeid | — | (707) 328 7016 | GC, remodel, ADU | Sonoma · Sonoma County | — | — |
| S G Construction | Samuel Garcia-Gonzales | — | (707) 849 3417 | GC, remodel, ADU | Windsor · Sonoma County | — | — |
| S J Cimino Electric INC | Salvatore Joseph Cimino | — | (707) 542 6231 | Electricians | Santa Rosa · Sonoma County | — | — |
| S J S Plumbing INC | Steven Patrick Dedrickson | — | (707) 658 1262 | Other | Petaluma · Sonoma County | — | — |
| S L F Concrete Construction INC | Shawn Lee Faull | — | (707) 836 8523 | Other | Windsor · Sonoma County | — | — |
| S L M Builders | Stephen Lucas Moreno | — | (707) 795 4177 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| S M Landscaping | S M Landscaping | — | (707) 774 2993 | Windows, patio, painters | Santa Rosa · Sonoma County | — | — |
| S P Plumbing | S P Plumbing | — | (707) 217 9620 | Other | Santa Rosa · Sonoma County | — | — |
| S Pratt Construction | Shawn Patrick Pratt | — | (707) 483 3659 | GC, remodel, ADU | Guerneville · Sonoma County | — | — |
| S R Allied Builders INC | Michael Alan Boyd | — | (707) 795 6595 | GC, remodel, ADU | Cotati · Sonoma County | — | — |
| S R F Concrete | S R F Concrete | — | (707) 782 6813 | Other | Rohnert Park · Sonoma County | — | — |
| S R Iron INC | Raul Carlos Sanchez | info@sriron.com | (707) 473 9740 | Other | Healdsburg · Sonoma County | — | — |
| S R Tile Design | S R Tile Design | — | (707) 799 1733 | Other | Santa Rosa · Sonoma County | — | — |
| S S Caveney Construction | Stuart Scott Caveney | — | (415) 531 3092 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| S S Construction | Spiodic Sanel | — | (510) 829 6402 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| S Simpson Electric | Sebastian Luther Simpson | — | (415) 728 5084 | Electricians | Petaluma · Sonoma County | — | — |
| S W Electric | Stephen Andrew Warner | — | (797) 695 7189 | Electricians | Windsor · Sonoma County | — | — |
| S W Quality Builders A Partnership | Donald Wayne Jr Martin | — | (415) 342 8661 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| S&k Handyma'am Services LLC | Sarah Jayne Stoelting | — | (707) 596 8117 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Sabri Abdelkhaliqu Zidan | Sabri Abdelkhaliqu Zidan | — | (415) 265 2596 | GC, remodel, ADU | Petaluma · Sonoma County | — | — |
| Saechao Construction | Alvin Kao Seng Saechao | — | (628) 254 4599 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Safe & Sound Connections | Safe & Sound Connections | — | (707) 799 1142 | Other | Santa Rosa · Sonoma County | — | — |
| Safe & Warm Chimney Services | Daniel Kasmar Schneider | — | (707) 792 2700 | Other | Rohnert Park · Sonoma County | — | — |
| Safer Properties - Real Estate / Property Management | Safer Properties - Real Estate / Property Management | — | (707) 978-4303 | Property managers | Rohnert Park · Sonoma County | — | — |
| Sagrero Construction | Jose Salud Sagrero | — | (707) 571 9270 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Saint Joseph Construction | Ruiz Jose Landin | — | (707) 480 7328 | GC, remodel, ADU | Santa Rosa · Sonoma County | — | — |
| Sal Concept Construction INC | Salvador Antonio Lopez | — | (707) 495 9702 | GC, remodel, ADU | Windsor · Sonoma County | — | — |