| Silvertree Construction | John Henry Draeger | — | (805) 235 0774 | GC, remodel, ADU | Grover Beach · San Luis Obispo County | — | — |
| Simco INC | Brandon Douglas Simonini | — | (805) 610 3603 | Other | Atascadero · San Luis Obispo County | — | — |
| Simmons Floor Covering | Simmons Floor Covering | — | (805) 705 2666 | Other | Nipomo · San Luis Obispo County | — | — |
| Simms Plumbing | Simms Plumbing | — | (928) 583 2153 | Other | Paso Robles · San Luis Obispo County | — | — |
| Simons Construction INC | Benjamin Raymond Simons | — | (805) 434 0217 | Electricians | Templeton · San Luis Obispo County | — | — |
| Simons Window Systems INC | Stanley Scott Simons | info@simonswindowsystems.com | (805) 464 2031 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Sims Excavating | Sims Excavating | — | (805) 710 1205 | Other | Nipomo · San Luis Obispo County | — | — |
| Sims Fire Protection INC | James Timothy Sims | — | (805) 712 7711 | Other | Santa Margarita · San Luis Obispo County | — | — |
| Sims Heating And Air Conditioning | Sims Heating And Air Conditioning | — | (805) 975 7140 | HVAC | Paso Robles · San Luis Obispo County | — | — |
| Simsco Plumbing Company | Nicholas Ross Sims | — | (805) 538 0230 | Other | Pismo Beach · San Luis Obispo County | — | — |
| Single Source Solutions | Single Source Solutions | — | (805) 801 7737 | Other | San Luis Obispo · San Luis Obispo County | — | — |
| Sinko Construction INC | Brett James Sinkovich | brett@sinkoconstruction.com | (805) 674 8163 | Other | Atascadero · San Luis Obispo County | — | — |
| Sir Grout Central Coast | Joshua David Frantz | — | (805) 868 6933 | Other | San Luis Obispo · San Luis Obispo County | — | — |
| Siteworx Construction INC | Kai Channin Silva | — | (805) 541 2060 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Sjl Builders | Sjl Builders | — | (805) 503 0398 | GC, remodel, ADU | Pismo Beach · San Luis Obispo County | — | — |
| Skelton Fencing | Skelton Fencing | joe@skeltonfencing.com | (830) 765-4684 | Other | Cholame · San Luis Obispo County | — | — |
| Skelton Welding | Skelton Welding | — | (916) 462 4038 | Other | Los Osos · San Luis Obispo County | — | — |
| Sks Real Estate And Development INC | Steven Richard Simoulis | — | (805) 440 9876 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Slabtown Construction | Chase David Tatham | — | (805) 395 0350 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Sligh Cabinets INC | Jordan Matthew Sligh | sales@slighcabinets.com | (805) 239 2550 | Other | Paso Robles · San Luis Obispo County | — | — |
| Slo Auto Glass & Tint | Slo Auto Glass & Tint | frontdesk@sloautoglassandtint.com | (805) 541-4527 | Windows, patio, painters | San Luis Obispo · San Luis Obispo County | — | — |
| Slo Build INC | Canaan Rhodes Lysobey | slobuild.construction@gmail.com | (805) 440 1054 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Slo Cal Builders LLC | Jonathan Edward Velasco | — | (805) 610 9129 | GC, remodel, ADU | Atascadero · San Luis Obispo County | — | — |
| Slo Circuit Electrical | Christopher Ryan Moore | — | (805) 440 7520 | Electricians | Los Osos · San Luis Obispo County | — | — |
| Slo Coast Construction | Christopher Leonard Pelzel | — | (805) 459 1618 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Slo County Construction INC | Diane Michele Helbert | — | (805) 471 3452 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Slo County Construction LLC | Jake Nicholas Carey | — | (805) 806 0280 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Slo County Modern Electric INC | James Michael Brown | — | (805) 674 0895 | Electricians | Morro Bay · San Luis Obispo County | — | — |
| Slo County Plumbing & Drain Cleaning INC | Paul Frederic Garcia | — | (805) 237 7586 | Other | Paso Robles · San Luis Obispo County | — | — |
| Slo Craft INC | Nicholas Patrick Hoover | info@slocraft.si | (805) 243 8303 | Electricians | San Luis Obispo · San Luis Obispo County | — | — |
| Slo Drip Landscapes | Slo Drip Landscapes | — | (805) 865 5001 | Windows, patio, painters | Cambria · San Luis Obispo County | — | — |
| Slo Dryer Vent Cleaning LLC | Gary Stanford Kibbe | — | (805) 250 1155 | GC, remodel, ADU | San Luis Obispo · San Luis Obispo County | — | — |
| Slo Gutters INC | Eric Lee Taylor | — | (805) 466 7013 | Other | Atascadero · San Luis Obispo County | — | — |
| Slo Landscaping INC | Robert Kenneth Triplett | rob@slolandscaping.com | (805) 458 2656 | Windows, patio, painters | San Luis Obispo · San Luis Obispo County | — | — |
| Slo Painting | Kevin Brent George | — | (508) 543 3976 | Windows, patio, painters | San Luis Obispo · San Luis Obispo County | — | — |
| Slo Plastering INC | Ryan Foster Hepperly | — | (805) 541 4750 | Other | San Luis Obispo · San Luis Obispo County | — | — |
| Slo Plumbing | Slo Plumbing | — | (805) 489 3800 | Other | Grover Beach · San Luis Obispo County | — | — |
| Slo Realty & Property Management | Slo Realty & Property Management | — | (805) 784-0946 | Property managers | San Luis Obispo · San Luis Obispo County | — | — |
| Slo Roofing INC | Christopher Demont Chase | — | (805) 458 7931 | Other roofers | Arroyo Grande · San Luis Obispo County | — | — |
| Slo Septic Pumping | Slo Septic Pumping | — | (805) 800 8931 | Other | Nipomo · San Luis Obispo County | — | — |