| Temper & Grit LLC | CC-01 | 2025 | Active |
| Tenon Construction LLC | CC-01 | 2016 | Renew by Dec 3, 2026 |
| Tera Painting & Construction | CC-01 | 2020 | Active |
| Terra Fern Studio LLC | CC-01 | 2025 | Active |
| Terra Firma II Inc | CC-01 | 2016 | Active |
| Terrain Seattle Co | CC-01 | 2009 | Active |
| Tex-Builders LLC | CC-01 | 2026 | Active |
| Thai Binh Construction Inc | CC-01 | 2006 | Active |
| The Best Practice | CC-01 | 2019 | Active |
| The CWD Group LLC | CC-01 | 2026 | Active |
| The Estate Butler LLC | CC-01 | 2025 | Active |
| The Fabricator LLC | CC-01 | 2019 | Active |
| The Fixit Sisters LLC | CC-01 | 2015 | Active |
| The Flying Locksmiths/Seattle | CC-01 | 2017 | Active |
| The Good Guys Builders Inc | CC-01 | 2024 | Renew by Dec 13, 2026 |
| The Grateful GC LLC | CC-01 | 2023 | Active |
| The Green Brush LLC | CC-01 | 2015 | Active |
| The Green Builder | CC-01 | 2021 | Active |
| The Handy One LLC | CC-01 | 2026 | Active |
| The Largest Lndscp & Const LLC | CC-01 | 2017 | Active |
| The Magic Painter LLC | CC-01 | 2022 | Renew by Nov 4, 2026 |
| The McKinney Group Inc | CC-01 | 2005 | Active |
| The Pacific Door LLC | CC-01 | 2022 | Active |
| The Steady Fix Co | CC-01 | 2025 | Active |
| The Workshop | CC-01 | 2026 | Active |
| The Wrightworks Const C SV LLC | CC-01 | 2026 | Active |
| Thermoroom LLC | CC-01 | 2023 | Active |
| Third Little Pig LLC | CC-01 | 2020 | Active |
| This Alt House LLC | CC-01 | 2026 | Active |
| Thistle & Stone | CC-01 | 2026 | Active |
| Thomas Development LLC | CC-01 | 2022 | Active |
| Thomas Fragnoli Construction | CC-01 | 2014 | Active |
| Thomas Group LLC | CC-01 | 2002 | Renew by Nov 27, 2026 |
| Thomas Jacobson Const Inc | CC-01 | 2008 | Active |
| Thoroughbred Investments LLC | CC-01 | 2025 | Active |
| Three Tree Construction LLC | CC-01 | 2020 | Renew by Dec 17, 2026 |
| Thriving Garden Design Inc | CC-01 | 2010 | Active |
| Thundor Construction LLC | CC-01 | 2023 | Active |
| Thurman Development Group Inc | CC-01 | 2013 | Active |
| Tian & Fei Granite & Cabinets | CC-01 | 2023 | Active |
| Tile &Drywall Solutions LLC | CC-01 | 2023 | Active |
| Timeless Spaces Sea LLC | CC-01 | 2026 | Active |
| Titan Air Duct & Chimney Srvcs | CC-01 | 2025 | Active |
| Tittel Enterprises Inc | CC-01 | 2000 | Active |
| Tj's Home Repair & Detail LLC | CC-01 | 2023 | Active |
| TM New Homes LLC | CC-01 | 2003 | Active |
| TN Landscape & Design LLC | CC-01 | 2022 | Renew by Dec 10, 2026 |
| TNT Contracting LLC | CC-01 | 2022 | Active |
| To The Roots LLC | CC-01 | 2026 | Active |
| Toa General Construction LLC | CC-01 | 2026 | Active |
| Tobin Roof Decks LLC | CC-01 | 2023 | Active |
| Todayhelp LLC | CC-01 | 2017 | Active |
| Todd Horner Const Services Inc | CC-01 | 2026 | Active |
| Tom McIntosh Glass&Glazing LLC | CC-01 | 2011 | Active |
| Toma Construction LLC | CC-01 | 2011 | Active |
| Tomeny Woodworks LLC | CC-01 | 2019 | Active |
| Tommy Builders Inc | CC-01 | 2025 | Active |
| Tooth-N-Nail | CC-01 | 2021 | Active |
| Top General Contractor LLC | CC-01 | 2020 | Active |
| Top House Construction | CC-01 | 2025 | Active |
| Top Modern Construction | CC-01 | 2026 | Active |
| Top Modern Homes | CC-01 | 2022 | Active |
| Top Notch Contractors LLC | CC-01 | 2026 | Active |
| Top Rail Fence Seattle | CC-01 | 2024 | Active |
| Total Construction LLC | CC-01 | 2017 | Active |
| Total Craft Builders LLC | CC-01 | 2026 | Active |
| Total Home Improvement Inc | CC-01 | 2003 | Active |
| Toth Construction Inc | CC-01 | 1985 | Active |
| TP General Construction LLC | CC-01 | 2024 | Active |
| TPC Services | CC-01 | 2026 | Active |
| TR Construction Service LLC | CC-01 | 2023 | Active |
| Tradition Additions LLC | CC-01 | 2025 | Active |
| Tran & Tanijo PLLC | CC-01 | 2021 | Active |
| Transco Northwest Inc | CC-01 | 1996 | Active |
| Tree City LLC | CC-01 | 2017 | Active |
| Tree Logic Energy PLLC | CC-01 | 2026 | Active |
| Tree Solutions Inc | CC-01 | 2009 | Active |
| Treebird LLC | CC-01 | 2004 | Active |
| Treefrog Lawn & Landscape LLC | CC-01 | 2026 | Active |
| Trend Development & DSGN LLC | CC-01 | 2010 | Renew by Nov 21, 2026 |
| Trillium Landscape Design LLC | CC-01 | 2023 | Active |
| Triple Bottom Line Cnstrtn SPC | CC-01 | 2018 | Active |
| Tripod LLC | CC-01 | 2021 | Active |
| Tristan Gary Designs LLC | CC-01 | 2019 | Active |
| Triton Graphic Displays LLC | CC-01 | 2017 | Active |
| Trowbridge LLC | CC-01 | 2018 | Active |
| True North LLC | CC-01 | 2010 | Active |
| True PNW Renovations LLC | CC-01 | 2026 | Active |
| True Scapes LLC | CC-01 | 2012 | Renew by Nov 15, 2026 |
| Truesquare Remodel LLC | CC-01 | 2025 | Active |
| Trung General Construction LLC | CC-01 | 2011 | Active |
| Tu'Akalau Constructions LLC | CC-01 | 2026 | Active |
| Tuck & Spade | CC-01 | 2021 | Active |
| Turner Construction Company | CC-01 | 1977 | Active |
| Turnercraft Const Servs LLC | CC-01 | 2024 | Renew by Dec 16, 2026 |
| Turnkey Builders Inc | CC-01 | 1996 | Active |
| Tuscany Garden LLC | CC-01 | 2022 | Active |
| Tutmarc Associates Inc | CC-01 | 1993 | Active |
| TW Homes LLC | CC-01 | 2024 | Active |
| TWC Development LLC | CC-01 | 2005 | Active |