| A B A Alarm Company Inc | C10 + B | 2004 | Active |
| A M P Electrical | C10 | 2016 | Active |
| A-Ev Installs | C10 | 2017 | Active |
| Aancs LLC | C10 + C31 | 2026 | Active |
| Accord Electric Corporation | C10 + A | 1990 | Active |
| Ae Solutions Inc | C10 + A | 2023 | Active |
| Ai-Tek | C10 + C7 | 2009 | Active |
| Alcoa Electrical Contractor Inc | C10 + A, C31 | 1995 | Active |
| Alcoa Traffic Control Inc | C10 + A, C31 | 2015 | Active |
| Alcoa Traffic Services Inc | C10 + A, C31 | 2026 | Active |
| All Right Electric Inc | C10 | 2007 | Active |
| American Restore Inc | C10 + B, C8, C27 +5 | 2012 | Active |
| Assured Roofing Pros Inc | C10 + B, C39 | 2018 | Active |
| Automated General Contracting Inc | C10 + B | 1991 | Active |
| Automation Installation Mechanical Electrical Inc | C10 + D34 | 2024 | Active |
| Beach City Electric Inc | C10 | 2004 | Active |
| Benny And The Joules Electric LLC | C10 | 2026 | Active |
| Beyond Surface Inc | C10 + B | 2017 | Active |
| BP Electric | C10 | 2025 | Active |
| Brady Construction And Design Inc | C10 + B | 2010 | Active |
| C&C Power Company Inc | C10 + A | 2025 | Active |
| Case | C10 + B | 2006 | Active |
| Cec Construction Engineering | C10 + A, B, C34 +2 | 2022 | Active |
| Coast Overhead Door & Electric Inc | C10 + D28 | 1987 | Active |
| Coastal Custom Electric Inc | C10 | 2020 | Active |
| Contorelli Construction Inc | C10 + A, B | 1976 | Active |
| Control Engineering Inc | C10 | 2012 | Active |
| Custom Electrical Solutions Inc | C10 | 2025 | Active |
| D T S Electric Inc | C10 | 2002 | Active |
| Day Electrical Services Inc | C10 | 2007 | Active |
| Drake Construction Inc | C10 + A, B, C6 | 2006 | Active |
| Dynamic Electrical Solutions Inc | C10 | 2012 | Active |
| Electrical Service Solutions Inc | C10 + A, D21, D28 | 2008 | Active |
| Electrical Systems Testing LLC | C10 + A | 2016 | Active |
| Electricians Service Express Inc | C10 + B | 2019 | Active |
| Electro Systems Electric Inc | C10 + B | 1987 | Active |
| Empire Plumbing Heating & Air Conditioning | C10 + B, C20, C36 +1 | 2001 | Active |
| Engineering And Environmental Construction Inc | C10 + A, B, C36 +1 | 2006 | Active |
| Express Power Services | C10 | 2024 | Active |
| Fieldtek Electric LLC | C10 + A | 2018 | Active |
| G & M Oil Company Inc | C10 + B, C36, D40 | 2006 | Active |
| Giland Inc | C10 + B, C54 | 2011 | Active |
| Gl3 Luxury Lighting LLC | C10 | 2026 | Active |
| Golden State Constructors | C10 + A, B | 2005 | Active |
| Gomez Builders & Contractors | C10 + B | 2009 | Active |
| Grani Installation Inc | C10 + C2, C9, D08 +1 | 1975 | Active |
| Griffith Electric & Construction Inc | C10 + B | 1990 | Active |
| Hanseth Electric Inc | C10 | 2006 | Active |
| Harbor View Electric | C10 | 2007 | Active |
| Huntington Beach Electric Inc | C10 + A | 2015 | Active |
| I D G | C10 | 2018 | Active |
| Intec Network Solutions Inc | C10 + C7 | 2008 | Active |
| J D K Electrical Inc | C10 + B | 1992 | Active |
| J G Solar Inc | C10 | 2018 | Active |
| Jim Was Here Inc | C10 + B, C6, C36 | 2000 | Active |
| John Christopher Construction Inc | C10 + B, C36 | 2015 | Active |
| KCT Electric | C10 | 2026 | Active |
| Kerber Electric | C10 | 2022 | Active |
| Kimble Fire | C10 + C16 | 2025 | Active |
| Latka Engineering Inc | C10 + A, B | 1995 | Active |
| Let It Glow Inc | C10 | 2023 | Active |
| Livinston Electric Corp | C10 | 2009 | Active |
| Mainland General & Electrical Contractors Inc | C10 + B | 2001 | Active |
| MJM Fire Protection | C10 + C16 | 2016 | Active |
| MJM Protection | C10 + C16 | 2004 | Active |
| MS Electrical Engineering Inc | C10 | 2025 | Active |
| Onshore Mechanical | C10 + C20, C38 | 2021 | Active |
| Optimum Electric | C10 | 2015 | Active |
| P B P S Inc | C10 + B, C53 | 1997 | Active |
| Pacific 3 Electric Inc | C10 | 1999 | Active |
| Pacific Breeze Building Solutions Inc | C10 + C27, C53, D03 | 2016 | Active |
| Pacific Power Electric | C10 + B | 2019 | Active |
| Pacific Rim Automation Inc | C10 | 1991 | Active |
| Pacific Utility Inc | C10 + B | 2007 | Active |
| Parrish Electric Inc | C10 | 1982 | Active |
| Portermatt Electric Inc | C10 + B | 2000 | Active |
| Premier Construction Solutions Inc | C10 | 2024 | Active |
| Pro-Lectric Inc | C10 | 1990 | Active |
| Progressive Electric Systems Inc | C10 | 1993 | Active |
| Q3 Builders Inc | C10 + B, C36 | 2017 | Active |
| R B E Construction Group Inc | C10 + B | 1990 | Active |
| R F P Inc | C10 + B, C16 | 2008 | Active |
| Redline Electric | C10 + B2 | 2016 | Active |
| Reilly Integrated Corporation | C10 | 2009 | Active |
| Relldan Inc | C10 + C7 | 2011 | Active |
| Rocal Electric Group | C10 + B | 2017 | Active |
| Rowe John Electric | C10 | 1999 | Active |
| S S B V Construction And Development Inc | C10 + B | 2021 | Active |
| Shorebreak Construction Inc | C10 + B | 2011 | Active |
| Southern California Energy Services Inc | C10 + B, C20 | 1991 | Active |
| Spriggs D C Inc | C10 | 1994 | Active |
| Stock Capital Holdings Inc | C10 | 2026 | Active |
| Sun Day Electric Inc | C10 | 2025 | Active |
| Surf City Sound Inc | C10 | 2009 | Active |
| Synergistic Matrix Inc | C10 + C7, D16 | 2009 | Active |
| Synovate Technologies Inc | C10 + B, C7 | 2010 | Active |
| Thomas Electric Company | C10 | 1986 | Active |
| TL Electric Inc | C10 | 2024 | Active |
| Torrey-Kelly Electric LLC | C10 | 2026 | Active |
| Troxy Enterprises Inc | C10 | 2005 | Active |