| Mar & Sons Construction Services Inc | B | 2025 | Active |
| Marca Construction Inc | B | 2014 | Active |
| Marcelo Antonio Construction Inc | B | 2019 | Active |
| Marcy Brothers Construction | B | 2025 | Active |
| Marina Landscape Inc | A, B + C27, C29, C36 +3 | 1986 | Active |
| Mark Company | A, B + C8 | 1970 | Active |
| Mass Form Builder | B | 2025 | Active |
| Materials Transport Services Inc | A | 2011 | Active |
| Mattson & Mattson Construction Inc | B | 1999 | Active |
| MB Construction | B + C33 | 2012 | Active |
| MBR Contractors Inc | B | 2024 | Active |
| McCormick Construction Services Inc | B + C17 | 2018 | Renew by Nov 30, 2026 |
| Metro Engineering Inc | A, B + C12 | 2018 | Renew by Nov 30, 2026 |
| Meyer Construction Services | B + C33 | 2002 | Active |
| Miller Environmental Inc | A, B + ASB, C21, C22 +3 | 1999 | Active |
| Mittmann & Company Inc | B | 2009 | Active |
| Modern Builders | A, B | 2024 | Active |
| Moffett Plumbing & Air | B + C20, C36 | 2003 | Active |
| Monarca Construction LLC | B | 2026 | Active |
| Monument Roofing | B + C39 | 2019 | Active |
| Mr Crane Inc | A | 1978 | Active |
| Nakae & Associates Inc | A + C27 | 1989 | Active |
| Native Builders Inc | A, B | 2020 | Active |
| Navarro Company | A | 2010 | Active |
| Navera Rino General Contracting Inc | B | 2010 | Renew by Oct 31, 2026 |
| Newbuild Construction And Restoration Inc | A, B + C17, C33 | 2016 | Active |
| Newland Construction Inc | B + C29 | 1984 | Active |
| Newman Backhoe Service Inc | A | 1970 | Active |
| Newman Windows & Doors Inc | B + C17, D28 | 2009 | Active |
| Newport Coast Construction Inc | B | 2024 | Active |
| Nexbuild Construction Group | B | 2026 | Active |
| No Limit Flooring | B + C15, C27, D06 | 2015 | Active |
| O C & C Construction | A, B + C31 | 2008 | Active |
| O C Elite Custom Remodel And Design | B2 | 2022 | Active |
| O'Donovan Construction Inc | A, B | 2007 | Active |
| Oc Professional Team Inc | B + C33 | 2020 | Active |
| Oc-Construction | B | 2007 | Active |
| Oceanview Builders | B | 2022 | Active |
| Olsson Construction Inc | A | 1999 | Active |
| Omni Contracting Inc | B | 2001 | Active |
| Orange Coast Petroleum Equipment Inc | A | 2004 | Active |
| Orange County Sandbagger | B + ASB, C20, C21 +7 | 1997 | Active |
| Orange Electrical Contractors Inc | A, B + C10 | 2004 | Active |
| Ortco Inc | B + D03, D12, D34 | 1992 | Active |
| Os Construction And Remodeling Inc | B | 2020 | Active |
| Osowski Construction Inc | B + C10 | 1982 | Active |
| Overwatch Amoroso LLC | A, B | 2022 | Active |
| P & E Construction Inc | B + C9, C21 | 1992 | Active |
| P R Construction Inc | B + C33 | 1993 | Active |
| P&M Innovations Builder | B | 2025 | Active |
| Pacific Coast Construction | B | 2024 | Active |
| Pacific Meridian Construction | B | 2019 | Active |
| Pacifico General Construction Inc | B + C33 | 2005 | Active |
| Padilla Construction Company | B + C35 | 1979 | Active |
| Painting & Decor Inc | B + C33 | 1972 | Active |
| Painting And Construction | B + C33 | 2017 | Active |
| Pallmar And Company | B + C6 | 1972 | Active |
| Patio Creations Inc | B | 2001 | Active |
| Patio Warehouse Inc | B + C8, C29, D03 | 2006 | Active |
| Patriot Paving Inc | A + C12 | 2009 | Active |
| Peak Renovations | B | 2024 | Renew by Nov 30, 2026 |
| Peavey Construction Inc | B | 2015 | Active |
| Pergomatic LLC | B | 2025 | Active |
| Philco Commercial Construction Inc | B | 1992 | Active |
| Philco Construction Inc | B | 1999 | Active |
| Pilot Painting & Construction | B + C33 | 2025 | Active |
| PL Remodeling Corp | B | 2021 | Active |
| Poppy General Contracting | B + C15 | 2024 | Active |
| Power Crane | A | 2025 | Active |
| PPM Construction Services | B + C8 | 2004 | Active |
| Prado's General Construction Inc | B | 2021 | Active |
| Precision Modern Remodeling Inc | B2 | 2025 | Active |
| Premier Construction And Renovation Inc | B | 2024 | Active |
| Premier One Improvements Inc | B + D28 | 2008 | Active |
| Premier Roofing & Building Co Inc | B + C39 | 1991 | Active |
| Probldrs | B | 2026 | Active |
| Project Blue Construction Group | A, B | 2022 | Active |
| Property Restoration Group | B | 2022 | Active |
| Provalue Construction | B | 2015 | Active |
| Prowest Engineering Inc | A | 2009 | Active |
| Purely Concrete Inc | B + C8 | 2025 | Active |
| Qualified Restoration Specialists Inc | B + ASB | 2010 | Active |
| Quality Kitchens Direct | B + C5, C6, C33 | 1987 | Active |
| Queale Construction Inc | B | 1998 | Active |
| Quest Preservation | B | 2011 | Active |
| R B P Construction Services Inc | B | 2015 | Active |
| R E Schultz Construction Inc | A, B + D12, D34 | 2015 | Active |
| R G H Construction Inc | B | 2017 | Active |
| R J Noble Company | A + C12 | 2000 | Active |
| R L Construction | B + C54 | 1989 | Active |
| R L Construction & Design Inc | B + C33 | 1989 | Active |
| R M W C O Inc | B + C27 | 1979 | Active |
| Raab Greg Construction Inc | B | 2007 | Active |
| Raymond - Northern California Inc | B + C2, C6, C9 +4 | 1975 | Active |
| Raymond-Southern California Inc | B + C2, C6, C9 +3 | 1966 | Active |
| Raymond-Standard A Joint Venture | B + C2, C6, C9 +3 | 2020 | Active |
| Rays Floors | B + C15 | 2017 | Active |
| Rb1 Construction Corp | B | 2023 | Active |
| RCR Traffic Specialist | B + C31, C32, D06 +4 | 2025 | Active |
| RDLS Development Inc | B | 2026 | Active |