| SGSavage Grace Wines | Underwood | WA | Beverage and Tobacco Product Manufacturing312130 | 1-19 | ◐ LIKELY ACTIVE |
| SPSchenk Packing CO INC | Mount Vernon | WA | Food Manufacturing311611 | — | ◐ LIKELY ACTIVE |
| SDScratch Distillery | Edmonds | WA | Beverage and Tobacco Product Manufacturing312140 | 1-19 | ◐ LIKELY ACTIVE |
| SNSeagen North Creek | Bothell | WA | Chemical Manufacturing325412 | — | ◐ LIKELY ACTIVE |
| SASealed Air Renton, WA | Renton | WA | Paper Manufacturing322223 | 20-99 | ◐ LIKELY ACTIVE |
| SCSEAMP Contech Engineered Solutions LLC | Arlington | WA | Fabricated Metal Product Manufacturing332322 | 1-19 | ◐ LIKELY ACTIVE |
| SBSeattle Barrel CO | Seattle | WA | Fabricated Metal Product Manufacturing332439 | — | ◐ LIKELY ACTIVE |
| STSedron Technologies LLC State Street | Sedro Woolley | WA | Fabricated Metal Product Manufacturing332420 | 20-99 | ◐ LIKELY ACTIVE |
| SPShamrock Paving INC | Spokane | WA | Petroleum and Coal Products Manufacturing324121 | — | ◐ LIKELY ACTIVE |
| SBShasta Beverages INC | Tukwila | WA | Beverage and Tobacco Product Manufacturing312111 | — | ◐ LIKELY ACTIVE |
| SUSheets Unlimited | Renton | WA | Paper Manufacturing322211 | 100-499 | ◐ LIKELY ACTIVE |
| SVSheridan Vineyard INC. | Zillah | WA | Beverage and Tobacco Product Manufacturing312130 | 1-19 | ◐ LIKELY ACTIVE |
| SCShope Concrete LLC | Puyallup | WA | Nonmetallic Mineral Product Manufacturing327332 | — | ◐ LIKELY ACTIVE |
| SCSilver Cat Farms | Chehalis | WA | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
| SISimonds International LLC Ridgefield | Ridgefield | WA | Fabricated Metal Product Manufacturing332216 | — | ◐ LIKELY ACTIVE |
| SSSiren Song Wines LLC | Chelan | WA | Beverage and Tobacco Product Manufacturing312130 | 1-19 | ◐ LIKELY ACTIVE |
| SRSkagit Ready Mix Mcfarland Road | Mount Vernon | WA | Nonmetallic Mineral Product Manufacturing327320 | — | ◐ LIKELY ACTIVE |
| SLSkookum Lumber Plant | Shelton | WA | Wood Product Manufacturing321113 | — | ◐ LIKELY ACTIVE |
| SOSleight of Hand Cellars | Walla Walla | WA | Beverage and Tobacco Product Manufacturing312130 | 1-19 | ◐ LIKELY ACTIVE |
| SLSmg LLC | Seattle | WA | Fabricated Metal Product Manufacturing332811 | 100-499 | ◐ LIKELY ACTIVE |
| SSSolar Spirits, LLC | Richland | WA | Beverage and Tobacco Product Manufacturing312140 | 1-19 | ◐ LIKELY ACTIVE |
| SFSolidus Fabrication and Design LLC | Carnation | WA | Transportation Equipment Manufacturing336611 | — | ◐ LIKELY ACTIVE |
| SPSound Propeller Services INC | Seattle | WA | Machinery Manufacturing333999 | 20-99 | ◐ LIKELY ACTIVE |
| SFSpecified Fittings INC | Bellingham | WA | Primary Metal Manufacturing331511 | — | ◐ LIKELY ACTIVE |
| SISpokane Industries | Spokane Valley | WA | Primary Metal Manufacturing331529 | 100-499 | ◐ LIKELY ACTIVE |
| SPSpokane Packaging | Spokane | WA | Paper Manufacturing322211 | 20-99 | ◐ LIKELY ACTIVE |
| SMSquak Mountain Materials INC | Issaquah | WA | Petroleum and Coal Products Manufacturing324121 | — | ◐ LIKELY ACTIVE |
| S4State 42 Wines LLC | Silverdale | WA | Beverage and Tobacco Product Manufacturing312130 | 1-19 | ◐ LIKELY ACTIVE |
| SPSteel Painters INC | Kelso | WA | Fabricated Metal Product Manufacturing332312 | — | ◐ LIKELY ACTIVE |
| SCStella-jones Corporation Bellingham | Bellingham | WA | Wood Product Manufacturing321999 | — | ◐ LIKELY ACTIVE |
| SStress-tek | Kent | WA | Computer and Electronic Product Manufacturing334519 | 20-99 | ◐ LIKELY ACTIVE |
| SWSuccession Wines, LLC | Manson | WA | Beverage and Tobacco Product Manufacturing312130 | 1-19 | ◐ LIKELY ACTIVE |
| SUSugiyo USA,Inc. | Anacortes | WA | Food Manufacturing311710 | 20-99 | ◐ LIKELY ACTIVE |
| SFSunleaf Farms | Mesa | WA | Food Manufacturing311615 | 1-19 | ◐ LIKELY ACTIVE |
| SCSunRype Concentrates | Wapato | WA | Food Manufacturing311411 | 20-99 | ◐ LIKELY ACTIVE |
| SCSuperior Custom Cabinets | Seattle | WA | Furniture and Related Product Manufacturing337110 | — | ◐ LIKELY ACTIVE |
| SFSuperior Fruit Equipment | East Wenatchee | WA | Fabricated Metal Product Manufacturing332216 | 20-99 | ◐ LIKELY ACTIVE |
| SHSwede Hill Cellars | Clinton | WA | Beverage and Tobacco Product Manufacturing312130 | 1-19 | ◐ LIKELY ACTIVE |
| SESynchronized Enterprises, INC. | Puyallup | WA | Primary Metal Manufacturing331210 | 20-99 | ◐ LIKELY ACTIVE |
| STSystima Technologies INC | Mukilteo | WA | Fabricated Metal Product Manufacturing332994 | — | ◐ LIKELY ACTIVE |
| TPTacoma Public School District 10 | Tacoma | WA | Primary Metal Manufacturing331222 | — | ◐ LIKELY ACTIVE |
| TTanjuli | Zillah | WA | Beverage and Tobacco Product Manufacturing312130 | 1-19 | ◐ LIKELY ACTIVE |
| TBT Bailey March Point Rd | Anacortes | WA | Fabricated Metal Product Manufacturing332420 | — | ◐ LIKELY ACTIVE |
| TTerramar | Edison | WA | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
| TPTetra Pak Materials LP | Vancouver | WA | Paper Manufacturing322215 | — | ◐ LIKELY ACTIVE |
| TLThe Lighthouse for the Blind, Incorporated | Spokane | WA | Fabricated Metal Product Manufacturing332999 | — | ◐ LIKELY ACTIVE |
| TSThe Scoular Company - Burlington | Burlington | WA | Food Manufacturing311710 | 20-99 | ◐ LIKELY ACTIVE |
| TTThe Truss Company | Sumner | WA | Wood Product Manufacturing321214 | 100-499 | ◐ LIKELY ACTIVE |
| TTThe Truss Company and Building Supply-pasco | Pasco | WA | Wood Product Manufacturing321214 | 20-99 | ◐ LIKELY ACTIVE |
| TOThomas O'neil Cellars | Richland | WA | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |