| 10-20 Services | C10 + C20 | 2015 | Active |
| 1st Team All Electrical | C10 | 2026 | Active |
| 1st Touch Electric Inc | C10 | 2015 | Active |
| Aaron Alt Construction Inc | C10 + B | 2016 | Active |
| Acc & Engineering LLC | C10 + A, B, C20 +1 | 2021 | Active |
| Accion Electric Inc | C10 + B | 2017 | Active |
| Advanced Improvements Inc | C10 + B, C20, C36 +1 | 2010 | Active |
| Aegis Construction Group Inc | C10 + B | 2019 | Active |
| Air Flow Control Air JV | C10 + A, B, C2 +3 | 2019 | Active |
| Albireo Energy | C10 | 1994 | Active |
| Allied Industrial Systems Inc | C10 + B | 1989 | Active |
| Alpha Electric Inc | C10 | 2024 | Active |
| Alpha Energy Group Inc | C10 + B, C20, C36 | 2010 | Renew by Dec 31, 2026 |
| American Independent Security | C10 + C7 | 1991 | Active |
| Amp't Electric Inc | C10 | 2008 | Active |
| Amped Electric Inc | C10 | 2023 | Active |
| Anointekus Inc | C10 + B | 2022 | Active |
| Ap Building Maintenance Inc | C10 + B, C33 | 2019 | Active |
| Arrow Electric Construction Services Inc | C10 | 2015 | Active |
| Astra Builders Inc | C10 + A, B | 2002 | Active |
| Audio Concepts | C10 | 2019 | Active |
| Avalon Fire Protection | C10 + C16 | 2000 | Active |
| BKD Electric Inc | C10 | 2022 | Active |
| Blackline Electric | C10 | 2026 | Active |
| BMV Electric Inc | C10 | 2016 | Active |
| Brooks Emergency Communications LLC | C10 + C7 | 2022 | Active |
| Building Air Systems | C10 + C20 | 2017 | Active |
| C.R.I Electric | C10 | 2026 | Active |
| Cable - Com Solutions | C10 + ASB, C7 | 2011 | Active |
| California Gate And Entry Systems | C10 + B, C7, D28 | 1987 | Active |
| Castle Defense | C10 | 2023 | Active |
| Chariot Fire & Integration | C10 | 2012 | Active |
| Cintas Fire Protection | C10 + C16 | 2008 | Active |
| Coast To Coast Electric | C10 | 2025 | Active |
| Comex Low Voltage Security Systems | C10 + C7 | 2019 | Active |
| Consulting Technology Network Inc | C10 + C7, D28 | 2012 | Active |
| Control Air Enterprises LLC | C10 + B, C2, C4 +3 | 2019 | Active |
| Convention Technical Services Inc | C10 | 1999 | Active |
| Coolets Heating And Airconditioning Inc | C10 + C20 | 2024 | Active |
| Cornerstone Electrical Services Inc | C10 | 2007 | Active |
| Direct Source Industrial Solutions Inc | C10 | 2015 | Active |
| Diversified Thermal Services LLC | C10 + B, C20, C38 | 1991 | Active |
| Donco & Sons Inc | C10 + B, C45, D40 | 1983 | Active |
| Ducros Electrical Contracting | C10 | 2024 | Active |
| Ducros Electrical Contracting & Design Inc | C10 | 1998 | Active |
| E V C R C Inc | C10 | 2024 | Active |
| Eclipse Lighting & Electrical | C10 | 2012 | Active |
| Econolite Systems Inc | C10 | 2012 | Active |
| Edessa Construction Inc | C10 + A, B, C33 +1 | 2001 | Active |
| Electric Diablo | C10 | 2025 | Active |
| Electrical Options Inc | C10 | 2019 | Active |
| Electrician Services Corp | C10 + B, C20 | 2005 | Active |
| Elite Construction | C10 + B | 2021 | Active |
| Elite Modern Builders LLC | C10 + B | 2020 | Active |
| Executive Lighting & Electric | C10 | 1993 | Active |
| Exterior Products Corporation | C10 + D42 | 2010 | Active |
| Far Builders | C10 + B | 2011 | Active |
| Fire Service Corp | C10 + C16, C36 | 2010 | Active |
| Fitzhauer Construction Inc | C10 + B, C20, C39 | 2015 | Active |
| Fortel Electric | C10 | 2010 | Active |
| G R C Industrial Electric | C10 | 2024 | Active |
| Gaboras Electric LLC | C10 | 2026 | Active |
| Gamboa Mark Construction LLC | C10 + B, C36 | 2003 | Active |
| Generation 3 Electric | C10 | 2025 | Active |
| Global Electric | C10 + C7 | 2009 | Active |
| Golden Hand Construction Inc | C10 + B | 2021 | Active |
| Goldeneagle Construction Inc | C10 + B | 2026 | Active |
| Gordon & Sons Electric Inc | C10 | 2002 | Active |
| H M Code Electric | C10 | 2019 | Active |
| H M Electric Inc | C10 | 2018 | Active |
| Handycrew Services Inc | C10 + B, C9, C33 | 2014 | Active |
| Home Comfort USA Heating & Cooling | C10 + C2, C20, C36 | 2023 | Active |
| Howard's Construction | C10 + B | 1993 | Active |
| HR Solar Inc | C10 | 2024 | Active |
| Immediate Fire Protection Inc | C10 + C16 | 2018 | Active |
| Indian Energy LLC | C10 | 2025 | Active |
| Integrity Electric | C10 | 2001 | Active |
| J D F Construction Inc | C10 + ASB, B, C17 +3 | 2011 | Active |
| J J E Electric Inc | C10 | 2023 | Active |
| James Electric Inc | C10 + B, C21 | 1992 | Active |
| Jcor Plumbing & General Contractor Anaheim | C10 + B, C36 | 2018 | Active |
| JM Brothers Electric Inc | C10 | 2024 | Active |
| JMX Electrical Inc | C10 | 2025 | Active |
| Kedin L Construction Inc | C10 + B | 2021 | Active |
| Kore Construction | C10 + B, C36, C39 | 2021 | Active |
| L U Electric Inc | C10 + B | 1990 | Active |
| Let There Be Light Electric Inc | C10 | 2022 | Active |
| Lindley Fire | C10 + A, C16, C34 | 2018 | Active |
| Lindley Systems Alarm Inc | C10 | 2023 | Active |
| Link4 Corporation | C10 | 2022 | Active |
| LLP Power Electric | C10 | 2024 | Active |
| Los Gavilanes Electric Inc | C10 | 2019 | Active |
| M P S Electric Inc | C10 | 2008 | Active |
| M S L Electric Inc | C10 | 2003 | Active |
| Magnetic Electric Inc | C10 | 1998 | Active |
| Mako Overhead Door Inc | C10 + C17, C28, D16 +1 | 1991 | Active |
| Mammoth Electric Inc | C10 | 1995 | Active |
| Mlife Builder Inc | C10 + B | 2020 | Active |
| N S W C Mechanical Service LLC | C10 + C20, C36, C38 | 2017 | Active |
| Nationwide Electric Inc | C10 | 2024 | Renew by Dec 31, 2026 |