| 24 Kva Electric Inc | C10 | 2024 | Active |
| 79 Electrical Services Inc | C10 | 2010 | Active |
| A & B Security | C10 | 1996 | Active |
| A & D Electric Inc | C10 | 2021 | Active |
| A & S Electrical | C10 | 2016 | Active |
| A 1 Electrical | C10 + B | 2008 | Active |
| A A A Electrical Services Inc | C10 + C20 | 1992 | Active |
| A A A Electrical Solutions Inc | C10 | 2016 | Active |
| A-Team Electric LLC | C10 | 2026 | Active |
| Abm Building Solutions LLC | C10 + B, C4, C7 +6 | 2012 | Active |
| Acqua Inc | C10 + C31, C34, C36 | 2026 | Active |
| Advance Sound & Electronics | C10 + C7 | 1971 | Active |
| Advanced Business Communications | C10 + B, C7, C33 | 2001 | Active |
| Agard Millwork And Construction | C10 + B, C6 | 2015 | Active |
| Air & Lube Systems Inc | C10 + A, B, D21 +1 | 1973 | Active |
| Air Cool Heating & Cooling Inc | C10 + B, C20 | 2007 | Active |
| Airco Mechanical Inc | C10 + A, B, C2 +8 | 1975 | Active |
| Alamo Electric | C10 | 1995 | Renew by Dec 31, 2026 |
| Alcalas Electrical Contracting Inc | C10 | 2014 | Active |
| Ali Electric Inc | C10 | 2022 | Active |
| All Season Construction Solution | C10 + B | 2023 | Active |
| All Valley Electrical Services | C10 | 2010 | Active |
| All Year Inc | C10 + B, C2, C20 +1 | 1981 | Active |
| Alliance Fire Alarms | C10 | 2008 | Renew by Dec 31, 2026 |
| Alpha Pacific Concrete | C10 + A, B, C8 | 2013 | Active |
| Alpha Tower Alarm Co | C10 | 2021 | Active |
| Alta Volt Electric LLC | C10 | 2026 | Active |
| Alvarado's Inc | C10 | 2024 | Active |
| Americana Electric Company | C10 | 2023 | Active |
| Amplified Electrical Services LLC | C10 | 2024 | Active |
| Anderson Central Valley Operations Inc | C10 + C7 | 2019 | Active |
| Andrey Electric Inc | C10 | 2025 | Active |
| Ar Power & Lighting | C10 | 2026 | Active |
| Arctic HVAC Solutions | C10 + B, C20, C36 | 2024 | Active |
| Artisan Grid Services Inc | C10 | 2025 | Active |
| Artwork Unlimited Inc | C10 + B, C36 | 2010 | Renew by Nov 30, 2026 |
| Atticman Heating & Air Conditioning Insulation Inc | C10 + C2, C20, C36 | 2018 | Active |
| Auburn Constructors LLC | C10 + A, B | 2018 | Active |
| Av-Ray Electrical Services Inc | C10 | 2026 | Active |
| Avail Services Inc | C10 | 2011 | Active |
| Axumax Inc | C10 | 2026 | Active |
| B - Line Construction Inc | C10 + B, C33, C36 | 1999 | Active |
| B And R Electric And Design LLC | C10 | 2026 | Active |
| B Line Construction LLC | C10 + B, C36 | 2025 | Active |
| B N V Electric Inc | C10 | 2024 | Active |
| Barnum & Celillo Electric Inc | C10 + C46, D56 | 1990 | Active |
| Bates Construction Company | C10 + A, B, C20 +1 | 1990 | Active |
| Bec Industrial | C10 + B, D21, D24 +1 | 2024 | Renew by Dec 31, 2026 |
| Benning Design Construction | C10 + B, C36 | 2002 | Active |
| Black Wolf Solar LLC | C10 | 2026 | Active |
| Bonham Electric Inc | C10 | 2007 | Active |
| Borrelli's Electric Inc | C10 + B | 2011 | Active |
| Bosley Electric Contracting Company | C10 + B, C36 | 1979 | Active |
| Boykin Electrical & Associates | C10 | 2006 | Renew by Nov 30, 2026 |
| Bozem Electric | C10 | 2026 | Active |
| Brighton Solar Inc | C10 + C46 | 2019 | Active |
| Brocchini Enterprises Inc | C10 + B, C20 | 2011 | Active |
| Brooks & Sons Ielectric Company | C10 | 2026 | Active |
| Buck Electric | C10 | 2026 | Active |
| Builder Construction | C10 + B, D41 | 2022 | Active |
| C C C S Inc | C10 + B | 2003 | Active |
| Cabar Electric Inc | C10 | 1986 | Active |
| California Automation Experts LLC | C10 | 2026 | Active |
| California Power Test Inc | C10 | 2002 | Active |
| Calivolt Electrical | C10 | 2026 | Active |
| Capitol Valley Electric Inc | C10 | 2005 | Active |
| Capitol Valley Electric LLC | C10 | 2021 | Active |
| Certifire Electric Inc | C10 + C16 | 2006 | Active |
| Chargewizards Construction LLC | C10 | 2025 | Active |
| City Line Electric | C10 | 2026 | Active |
| Clarion Electric Incorporated | C10 | 2004 | Active |
| Clean Energy Services Ces LLC | C10 | 2026 | Active |
| Comfort Systems Construction Inc | C10 + B, C20, C46 | 1988 | Active |
| Commercial And Residential Electrical LLC | C10 | 2026 | Active |
| Continental Electric Inc | C10 | 1989 | Active |
| Continuum | C10 + C39 | 2021 | Active |
| Cool Air Inc A | C10 + C20 | 2007 | Active |
| Cooper Oates Air Conditioning Inc | C10 + C20, C36, C38 +1 | 1991 | Active |
| Copper Hawk Electric | C10 | 2026 | Active |
| Coyote Electric | C10 | 2025 | Active |
| Crime Alert Security Enterprises Inc | C10 | 2014 | Active |
| Crocker Electric Incorporated | C10 | 2009 | Active |
| CVC Electric LLC | C10 | 2024 | Active |
| D P K Electric LLC | C10 | 2024 | Active |
| D4 Electric Inc | C10 | 2009 | Active |
| Destiny Electric | C10 | 2023 | Active |
| Diamond Grit Construction Inc | C10 + B | 2025 | Active |
| Dream Builder Construction + Development | C10 + B | 2019 | Active |
| Durham Paul Electric Inc | C10 | 1975 | Active |
| Eccl Solutions Inc | C10 + A, B | 2025 | Active |
| Ecowise Electric LLC | C10 | 2026 | Active |
| Edward R Bacon Company Inc | C10 + A, B | 2007 | Active |
| Efficient Energy Solutions Inc | C10 + B, C2, C17 +5 | 1978 | Active |
| Ejm Electric LLC | C10 | 2026 | Active |
| Electric City Sacramento | C10 | 2013 | Active |
| Electrical Communications Solutions | C10 | 2025 | Active |
| Electrical Gurus Co | C10 | 2024 | Active |
| Electrified Inc | C10 | 2017 | Active |
| Elevation Energy Solutions Inc | C10 + B | 2024 | Renew by Dec 31, 2026 |
| Elite Electric | C10 | 2026 | Active |