| I5 Electric LLC | EC-01 | 2024 | Active |
| Industrial Communications LLC | EC-06 | 2023 | Active |
| Industrialsoft Inc | EC-01 | 1998 | Active |
| Infinity Cable LLC | EC-01 | 2025 | Active |
| Integrity Home Solution NW LLC | EC-01 | 2022 | Active |
| Johnson Barrow LLC | EC-01 | 2025 | Active |
| Joseph Electric LLC | EC-01 | 2025 | Active |
| Joseph Electric LLC | EC-02 | 2023 | Active |
| Juicer Energy Inc | EC-01 | 2025 | Active |
| Kaplan Electric LLC | EC-01 | 2023 | Active |
| KB Electric Service Incorporat | EC-01 | 2004 | Active |
| Keithly Electric Co | EC-01 | 1990 | Active |
| Kemly Electric Inc | EC-01 | 1997 | Active |
| Konsker Electric LLC | EC-01 | 2013 | Active |
| L C M Builders LLC | EC-01 | 2025 | Active |
| Link Communication Inc | EC-09 | 2004 | Active |
| Logos Electric | EC-02 | 2026 | Active |
| Low Income Housing Institute | EC-7B | 2002 | Active |
| LT Electric | EC-01 | 2026 | Active |
| Lynsen Electronics Corp | EC-01 | 1991 | Active |
| Macdonald-Miller Fac Solns LLC | EC-01 | 2025 | Active |
| Man Electric LLC | EC-01 | 2025 | Active |
| Masters Electric & Com LLC | EC-01 | 2008 | Active |
| Max Technologies LLC | EC-06 | 2010 | Active |
| McKinstry Co LLC | EC-01 | 2006 | Active |
| Mechanical Serv & Intrgrtn LLC | EC-01 | 2018 | Renew by Dec 21, 2026 |
| Mei Electric LLC | EC-01 | 2025 | Active |
| Method Energy LLC | EC-01 | 2023 | Active |
| Method LLC | EC-01 | 2023 | Active |
| Metropolitan Appliance Company | EC-7D | 2016 | Active |
| Milsteadt Electric West Inc | EC-01 | 2024 | Active |
| Mirsky Electric Inc | EC-01 | 2004 | Active |
| Mr Electric Of Seattle-Nrthgt | EC-02 | 2025 | Active |
| N C Power Systems Co | EC-07 | 2015 | Active |
| National Sign Corporation | EC-04 | 1997 | Active |
| Need Electrical Contractor LLC | EC-01 | 2025 | Active |
| Nelson Electric Inc | EC-01 | 1987 | Active |
| Neptune Electric Co | EC-01 | 2009 | Active |
| NG Electric LLC | EC-01 | 2024 | Renew by Dec 24, 2026 |
| Noble Neon LLC | EC-04 | 2016 | Active |
| Nortech Electric | EC-01 | 2015 | Active |
| North 48 Electrical & Son LLC | EC-01 | 2023 | Active |
| NW Low Voltage & Security LLC | EC-06 | 2007 | Active |
| Ohm Electrical Contracting LLC | EC-01 | 2017 | Active |
| Olson Energy Serv/Gas Appl Svc | EC-02 | 2014 | Renew by Oct 29, 2026 |
| Olympic Hot Tub Co | EC-07 | 2001 | Active |
| Overton Electric LLC | EC-01 | 2024 | Active |
| Ovixi LLC | EC-06 | 2025 | Active |
| Pakko Electric Inc | EC-01 | 2007 | Active |
| Power To The PPL Energy LLC | EC-01 | 2024 | Active |
| Practical Electric LLC | EC-01 | 2025 | Active |
| Proeltel Electric LLC | EC-01 | 2026 | Active |
| PSR Mechanical LLC | EC-07 | 2020 | Active |
| Puget Sound Energy Inc | EC-01 | 1997 | Active |
| Puget Sound Solar LLC | EC-01 | 2008 | Renew by Dec 8, 2026 |
| PWR Consultants & Contrg Inc | EC-01 | 2001 | Active |
| Qnorthwest LLC | EC-01 | 2010 | Active |
| Queen Anne Electric LLC | EC-01 | 2009 | Active |
| R B White Electric Inc | EC-01 | 1985 | Active |
| Rad-Wire Electric LLC | EC-01 | 2025 | Active |
| Region 6 Sec Integration LLC | EC-01 | 2025 | Active |
| Remix Creative LLC | EC-06 | 2023 | Active |
| Rezelectric LLC | EC-01 | 2013 | Active |
| Riteway Electrical & Const Inc | EC-01 | 2001 | Active |
| Roanoke Electric LLC | EC-02 | 2025 | Active |
| Robinson Electric LLC | EC-01 | 2020 | Active |
| RPC Electric LLC | EC-01 | 2017 | Active |
| S C G Electric Inc | EC-01 | 1991 | Active |
| S T S Remodeling Corp | EC-02 | 2025 | Active |
| Safety Team Inc, The | EC-06 | 1984 | Active |
| Schneider Electric Inc | EC-01 | 1999 | Active |
| SD Electrical Services LLC | EC-01 | 2022 | Active |
| Seattle Electric | EC-01 | 2008 | Active |
| Seattle Marysville Const LLC | EC-01 | 2024 | Active |
| Seattle Satellite | EC-09 | 2001 | Active |
| Seattle Sparkies | EC-01 | 2026 | Active |
| Sevan Systems | EC-06 | 2025 | Active |
| Solterra Global LLC | EC-01 | 2017 | Active |
| Spectrum Electrical Srvcs Co | EC-01 | 1993 | Active |
| Sphere Solar Energy LLC | EC-01 | 2016 | Active |
| Spire Electrical Services LLC | EC-01 | 2005 | Active |
| SPR Electric LLC | EC-02 | 2026 | Active |
| Star Power Electric LLC | EC-01 | 2025 | Active |
| Stratford Managment Co LLC | EC-01 | 2023 | Active |
| Streamline Solutions LLC | EC-06 | 2010 | Active |
| Sullivan Electric & Light LLC | EC-01 | 2006 | Active |
| Sun Path Electric LLC | EC-01 | 2018 | Active |
| Sunergy Systems Inc. | EC-01 | 2010 | Active |
| Sunshine Electrical Sltns LLC | EC-02 | 2025 | Active |
| Surge Dynamics LLC | EC-01 | 2024 | Active |
| Syndicate Electric LLC | EC-01 | 2024 | Active |
| Synergy Communication LLC | EC-09 | 2012 | Active |
| Techpros LLC | EC-06 | 2006 | Active |
| Teldata Systems Inc | EC-06 | 2001 | Active |
| The Electric Co of Seattle Inc | EC-01 | 1998 | Active |
| Thomas Bell Electric | EC-01 | 1999 | Active |
| Town Elctrc, Plmbng & HTNG LLC | EC-01 | 2017 | Active |
| Tribal Electric LLC | EC-01 | 2019 | Active |
| Trion Electric LLC | EC-01 | 2023 | Active |
| Triton Graphic Displays LLC | EC-04 | 2020 | Active |