| Slobispo Remodelers | Slobispo Remodelers | — | (805) 874-5889 | Restoration | Grover Beach · San Luis Obispo County | — | — |
| Slomow | Natalie Quin Lee | — | (805) 439 0911 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Sloright County Property Management | Sloright County Property Management | info@sloright.com | (805) 540-2121 | Property managers | San Luis Obispo · San Luis Obispo County | — | — |
| Slw Homes | Slw Homes | — | (805) 503 0258 | GC, remodel, ADU | Arroyo Grande · San Luis Obispo County | — | — |
| Smee's Plumbing | Smee's Plumbing | service@smeesplumbing.com | (805) 544 8971 | Other | San Luis Obispo · San Luis Obispo County | — | — |
| Smeland Construction Service's | Curt Patrick Smeland | — | (831) 998 1855 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Smeltzer Construction | Kevin George Smeltzer | — | (805) 467 3840 | GC, remodel, ADU | San Miguel · San Luis Obispo County | — | — |
| Smith Construction | Nathan Dean Smith | — | (805) 710 7606 | GC, remodel, ADU | Pismo Beach · San Luis Obispo County | — | — |
| Smitty Built Construction Co | Christopher Dale Smith | — | (805) 610 9072 | GC, remodel, ADU | Paso Robles · San Luis Obispo County | — | — |
| Snow Electric | Christopher Alan Snow | — | (805) 459 1668 | Electricians | Arroyo Grande · San Luis Obispo County | — | — |
| Snyder And Sons Landscapes INC | Daniel Robert Snyder | — | (805) 748 7292 | Windows, patio, painters | Los Osos · San Luis Obispo County | — | — |
| Snyder Custom Construction INC | Gregory David Snyder | — | (805) 452 6747 | GC, remodel, ADU | Arroyo Grande · San Luis Obispo County | — | — |
| Snyder Electric | Gary Robert Snyder | interested@domainmarket.com | (805) 540 4560 | Electricians | Paso Robles · San Luis Obispo County | — | — |
| Soares Plumbing | Soares Plumbing | — | (805) 863 2508 | Other | Nipomo · San Luis Obispo County | — | — |
| Socom Underground | Billy Gene Jr Kilmer | — | (805) 835 7201 | Other | Paso Robles · San Luis Obispo County | — | — |
| Solarponics INC | Anna-Louise Emrich | — | (805) 466 5595 | HVAC | Atascadero · San Luis Obispo County | — | — |
| Solect Electric | Stephen Craig Slaughter | — | (805) 544 9549 | Electricians | San Luis Obispo · San Luis Obispo County | — | — |
| Solomon Electric | Jacob Mark Solomon | solomonelectric@yahoo.com | (661) 205 4084 | Electricians | San Luis Obispo · San Luis Obispo County | — | — |
| Sonny Tyndall | Sonny Tyndall | — | (661) 312 1411 | Other | Paso Robles · San Luis Obispo County | — | — |
| Sotello Construction Corp | Robert Gilbert Sotello | — | (805) 295 9347 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Soto Construction | Soto Larez Bonifacio | — | (805) 674 6274 | GC, remodel, ADU | Shandon · San Luis Obispo County | — | — |
| Sousa Construction | Manuel Humberto Sousa | — | (916) 871 6442 | GC, remodel, ADU | Arroyo Grande · San Luis Obispo County | — | — |
| South Bay Electric | Kenneth Robin Johnson | — | (805) 610 8741 | Electricians | Paso Robles · San Luis Obispo County | — | — |
| South Bay Landscape | South Bay Landscape | — | (805) 704 9124 | Windows, patio, painters | Los Osos · San Luis Obispo County | — | — |
| South Shore Builders INC | Gordon Rene Jr Legault | — | (805) 310 9860 | GC, remodel, ADU | Paso Robles · San Luis Obispo County | — | — |
| South Swell Electrical | South Swell Electrical | — | (805) 242-3132 | Electricians | San Luis Obispo · San Luis Obispo County | — | — |
| Southpaw Design & Construction INC | Donald Robert Mc Adam | — | (805) 221 4038 | GC, remodel, ADU | Paso Robles · San Luis Obispo County | — | — |
| Southpaw Sign Company INC | Michael Sean Beauchamp | — | (805) 474 5700 | Other | Oceano · San Luis Obispo County | — | — |
| Southwest Fence And Supply | Christopher Lee Hanneken | — | (805) 635 4940 | GC, remodel, ADU | Paso Robles · San Luis Obispo County | — | — |
| Souza Engineering Contracting INC DBA Souza Construction | Steve Anthony Souza | — | (805) 546 8288 | Other | San Luis Obispo · San Luis Obispo County | — | — |
| Spafford Drywall Metal Framing | Spafford Drywall Metal Framing | — | (805) 423 3786 | Other | Paso Robles · San Luis Obispo County | — | — |
| Sparkle Electric | Emelia Paulsen Loomis | — | (805) 550 1304 | Electricians | Arroyo Grande · San Luis Obispo County | — | — |
| Spatafore Construction | Rhett Blair Spatafore | — | (805) 459 8521 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Specialty Construction | Rudolph Charles Bachmann | info@specialtyconstruction.com | (805) 543 1706 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Specialty Constructors Services INC | Jose Trinidad Rodriguez | — | (805) 550 2107 | GC, remodel, ADU | Grover Beach · San Luis Obispo County | — | — |
| Spectre Security INC | Spectre Security INC | — | (888) 764-8273 | Alarm and generators | San Luis Obispo · San Luis Obispo County | — | — |
| Spice Electrical | John Galen Bowers | — | (805) 464 4111 | Electricians | Oceano · San Luis Obispo County | — | — |
| Spike Construction | Ted Howard Groom | — | (805) 296 8881 | GC, remodel, ADU | Paso Robles · San Luis Obispo County | — | — |
| Spock Industries INC DBA Spock Industries Access Systems | Gene S Rhinehart | — | (805) 234 1119 | Other | Paso Robles · San Luis Obispo County | — | — |
| Springer Drywall INC | Martin Patrick Springer | — | (805) 868 4298 | Other | Grover Beach · San Luis Obispo County | — | — |