| 1 Tom Plumber Anaheim / Brea | C36 | 2014 | Active |
| 2 J's Custom Plumbing | C36 | 2022 | Active |
| 3 Brothers Plumbing Inc | C36 | 2023 | Active |
| 714 Plumbing Inc | C36 | 2023 | Active |
| A G Plumbing & Building Contractors Inc | C36 + B | 2009 | Active |
| Aaa Plumbing | C36 | 2024 | Renew by Nov 30, 2026 |
| Acc & Engineering LLC | C36 + A, B, C10 +1 | 2021 | Active |
| Accurate Industrial Construction Inc | C36 + B | 2006 | Active |
| Accurate Plumbing And Drains | C36 | 2016 | Active |
| Advanced Improvements Inc | C36 + B, C10, C20 +1 | 2010 | Active |
| Air Concepts | C36 + B, C20 | 1988 | Active |
| Air Flow Control Air JV | C36 + A, B, C2 +3 | 2019 | Active |
| Alabout Plumbing J & C Inc | C36 | 2017 | Active |
| All Domestic And Commercial Plumbing | C36 | 2024 | Renew by Nov 30, 2026 |
| All Plumbing Services 714 Inc | C36 | 2025 | Active |
| Alpha Energy Group Inc | C36 + B, C10, C20 | 2010 | Active |
| American International Engineering (Aie) | C36 + A, B | 2024 | Active |
| American Leak Detection Of San Diego | C36 + D64 | 2011 | Active |
| American Ranger Plumbing LLC | C36 | 2026 | Active |
| Anaheim Hills Plumbing LLC | C36 | 1993 | Active |
| Axis Mechanical Services | C36 + B, C16, D21 | 2008 | Active |
| B & B Plumbing Inc | C36 | 1990 | Active |
| Blyleven's Plumbing Inc | C36 | 1999 | Active |
| Bonilla's Plumbing Service USA Corp | C36 | 2025 | Active |
| Broke Plumbing Inc | C36 | 2022 | Active |
| Brownco Construction Company Inc | C36 + A, B, C8 +5 | 1999 | Active |
| Cal One Inc | C36 | 2024 | Active |
| Cal Pro Plumbing Inc | C36 | 2019 | Active |
| California Coast Plumbers Inc | C36 | 1997 | Active |
| California Coast Plumbing & Repiping Inc | C36 | 2006 | Active |
| Chief Construction Services Inc | C36 + B | 1993 | Active |
| Coast 2 Coast Plumbing Inc | C36 + B | 2007 | Active |
| Control Air Enterprises LLC | C36 + B, C2, C4 +3 | 2019 | Active |
| Cooper Andrew D Company | C36 + B, C20 | 1963 | Active |
| Coventry Construction Services Inc | C36 + B | 2025 | Active |
| Customer Care Plumbing & Drains | C36 | 2025 | Active |
| D G O Plumbing And Hydro Jet Services | C36 | 2019 | Active |
| Davart Pro Construction & Plumbing Inc | C36 + B | 2020 | Active |
| Donnie Smith Enterprises | C36 | 2002 | Active |
| DPR Incorporated | C36 | 2026 | Active |
| Earth & Sun Construction Inc | C36 + B, C20, C33 | 2020 | Active |
| Eco Home Solutions | C36 + B, C20 | 2014 | Active |
| Effective Builds | C36 + B, HAZ | 2022 | Active |
| Fire Service Corp | C36 + C10, C16 | 2010 | Active |
| First Option Plumbing Inc | C36 | 2014 | Active |
| Fit Flow Plumbing & Drains LLC | C36 | 2026 | Active |
| Fitzgerald Plumbing Service Company | C36 + C20 | 2024 | Renew by Nov 30, 2026 |
| Floform Block Tops LLC | C36 + B, C6, C54 +2 | 2024 | Active |
| FV Plumbing & Rooter Inc | C36 | 2025 | Active |
| Gamboa Mark Construction LLC | C36 + B, C10 | 2003 | Active |
| Gold Star Plumbing Service | C36 | 2018 | Active |
| H B A Incorporated | C36 + A, B, C8 +4 | 2006 | Active |
| Happy Cowboy Plumbing | C36 | 2021 | Active |
| Harp Plumbing Incorporated | C36 | 1987 | Active |
| HDZ Plumbing Services | C36 | 2024 | Active |
| Hellmuth Plumbing | C36 | 2025 | Active |
| High Caliber Plumbing HCP | C36 | 2025 | Active |
| Hobi Plumbing Inc | C36 | 2004 | Active |
| Home Builder Inc | C36 + B | 2018 | Active |
| Home Comfort USA Heating & Cooling | C36 + C2, C10, C20 | 2023 | Active |
| Iron Mountain Plumbing | C36 | 2023 | Active |
| Irvine Valley Air Conditioning Inc | C36 + A, C20 | 1992 | Active |
| J & SJ Contractors Inc | C36 + B, C33 | 1993 | Active |
| Jaguar Rooter And Plumbing LLC | C36 | 2026 | Active |
| James Lecourt Plumbing | C36 | 2025 | Active |
| JB Fire Protection Inc | C36 + C16, C34 | 1992 | Active |
| Jcor Plumbing & General Contractor Anaheim | C36 + B, C10 | 2018 | Active |
| JP Prime Inc | C36 | 2023 | Active |
| Kahuna Comfort Plumbing Heating & Air | C36 + C20, C42 | 2018 | Active |
| Klean Plumbing Inc | C36 | 2018 | Active |
| Kore Construction | C36 + B, C10, C39 | 2021 | Active |
| Labonte Plumbing Inc | C36 | 2006 | Active |
| Legacy Pro Plumbing | C36 | 2025 | Active |
| Lenora Plumbing Company | C36 | 2023 | Active |
| Linear Plumbing Inc | C36 | 2023 | Active |
| Liquid Plumbing Inc | C36 | 1976 | Active |
| Localized Plumbing | C36 | 2026 | Active |
| Magna Plumbing | C36 + C20 | 1991 | Active |
| Martinez Plumbing | C36 | 2023 | Active |
| MG Developer's Inc | C36 + B, C20 | 2012 | Active |
| Mr Rocco's Plumbing | C36 + B, C42 | 2015 | Active |
| Mr Rooter Plumbing | C36 + B, C42 | 1999 | Active |
| N S W C Mechanical Service LLC | C36 + C10, C20, C38 | 2017 | Active |
| Oc Plumbing & Backflow | C36 | 2024 | Active |
| One Shot Plumbing And Drains LLC | C36 | 2025 | Active |
| Orange County Drains | C36 | 2024 | Active |
| Owen Plumbing Inc | C36 | 2005 | Active |
| Pacific Coast Copper Repipe Inc | C36 | 1997 | Active |
| Pacific States Utility Company | C36 + A, B, C10 | 1976 | Active |
| Pelcastre's Plumbing | C36 | 2021 | Active |
| Pipedream Plumbing | C36 | 2003 | Active |
| Platinum Plumbing Services Co | C36 | 2002 | Active |
| Plumb Anything Inc | C36 | 2019 | Active |
| Plumbing Rescue Inc | C36 | 2026 | Active |
| Plumbing X Incorporated | C36 | 2023 | Active |
| Poco Joe's Plumbing Inc | C36 | 2007 | Active |
| Prestige Construction Enterprises Inc | C36 + B, C10, C33 | 2007 | Active |
| Prevent Backflow & Plumbing Inc | C36 | 1999 | Active |
| Prime Enc Inc | C36 + B, C20, C39 +1 | 2014 | Active |
| Pro Plumbing Solutions | C36 | 2026 | Active |