| Iron Path Corp | A, B + C7, C8, C10 +4 | 2026 | Active |
| J & A Structures Inc | A | 2018 | Active |
| J & H General Construction | B | 2021 | Active |
| J A Russo Enterprises Inc | B | 2000 | Active |
| J N B Interiors Inc | B + C9 | 2007 | Active |
| J*c Remodeling & Construction | B | 2022 | Active |
| JC & S Facility Management & Construction Inc | B | 2025 | Active |
| JD Builders Group | B | 2022 | Active |
| JFP Company | B + C33 | 1984 | Active |
| Jitney Company Inc | A, B + C10 | 1996 | Active |
| JLR Group Inc | A, B | 2026 | Active |
| Joseph P Development Corporation | B | 2013 | Active |
| Joud Construction Company Inc | B | 2003 | Active |
| Jshennawi Construction Inc | B | 2025 | Active |
| K E C Engineering | A + HAZ | 1995 | Active |
| Kaizen Builders Inc | B | 2026 | Active |
| Kirra Construction | B + C8 | 1998 | Active |
| KML Services Inc | A, B + ASB, C21, C22 +1 | 2013 | Active |
| Koi Construction LLC | B | 2026 | Active |
| L & H R Inc | A, B | 2020 | Active |
| L & S General Construction Inc | B | 2023 | Active |
| L B J Flooring Inc | B + C15 | 2005 | Active |
| L E I General Contractor | B + C5 | 1979 | Active |
| La Habra Welding Inc | A | 2004 | Active |
| Larco Development Inc | B | 1993 | Active |
| Laurence-Hovenier Inc | B | 1979 | Active |
| Legacy Builders So Cal Inc | B + C8, C29 | 2011 | Active |
| Legacy Framing Inc | B | 2026 | Active |
| Lewis Construction | B | 2024 | Active |
| Line Works Construction Inc | A + C10 | 2015 | Active |
| Lisardo Construction Inc | B | 2005 | Active |
| Livewell Restoration LLC | B + C20, C36 | 2022 | Active |
| Lopez Construction | A | 2007 | Active |
| Lopez Richard Construction Inc | A | 2011 | Active |
| Lucky Air & Plumbing | B + C20, C36 | 2004 | Active |
| Luxe Home Remodel Inc | B + C10, C36 | 2017 | Active |
| Luxen Builders | B | 2026 | Active |
| LV Builders Inc | B + C10 | 2023 | Active |
| M & M Construction Enterprises | B | 2004 | Active |
| M D H Quality Construction | B | 2020 | Renew by Dec 31, 2026 |
| M N O Engineering Inc | A | 2022 | Active |
| M T I Construction Inc | B | 2019 | Active |
| M&H Home Builders Corp | B | 2020 | Active |
| M&M Construction | B | 2021 | Active |
| Macuarro Construction Corporation | B | 2026 | Active |
| Madsen Homes Inc | B | 2001 | Active |
| Maestro Builders & Contractors | B | 2026 | Active |
| Mak Construction Inc | B | 2007 | Active |
| Mapes Construction Services | B | 2024 | Renew by Dec 31, 2026 |
| Martin-Standard A Joint Venture | B + C2, C9, C35 | 2026 | Active |
| Matcon General Engineering Inc | A | 2017 | Active |
| Mead Construction Inc | A, B + C8 | 2009 | Active |
| Mechling J Construction | B | 2019 | Active |
| MGM Renovations Inc | B | 2025 | Active |
| Miracle Playground Sales Inc | A | 2026 | Active |
| MLC Constructors Inc | A, B + C10, C20, C36 +1 | 2020 | Active |
| MMC Construction Company | B | 2020 | Active |
| Mode Renovation LLC | B | 2021 | Active |
| Moreno & Company Inc | B2 | 2025 | Active |
| Moreno Engineering Inc | A | 1998 | Active |
| Motive Energy Telecommunications Group LLC | A, B + C10 | 2025 | Active |
| Mountainside Construction Group | B | 2026 | Active |
| MPR Construction | B | 2024 | Renew by Dec 31, 2026 |
| MTC Contractor's Inc | A, B + C8 | 2001 | Active |
| Mynt Construction Services | B | 2024 | Active |
| MZB Engineering And Construction Incorporated | A | 2021 | Active |
| N P Mechanical Inc | B + C16, C20, C36 | 2007 | Active |
| National Renovation Inc | B + C20, C36, D12 | 2011 | Active |
| New Creation | B | 2024 | Active |
| Newport Building Company | B | 2026 | Active |
| Next Chapter Homes | B | 1981 | Active |
| Nikaro Construction Inc | B | 2016 | Active |
| O C Outdoor Construction Inc | B | 2018 | Active |
| Olah R B Inc | B | 2023 | Active |
| One Stop Premium Interior Remodels | B | 2025 | Active |
| Oracle Renovations | B2 | 2023 | Active |
| Orange County Home Maintenance & Remodeling | B | 2023 | Active |
| Ortiz General Builders Inc | B | 2023 | Active |
| Owen James Construction Inc | B | 2019 | Active |
| Oxidizers Inc | A, B | 1993 | Active |
| P B A Construction Inc | A, B + C10, C45, HAZ | 2010 | Active |
| Pacific Allied Group Inc | A, B | 2021 | Active |
| Pacific Environmental Technologies Inc | B + C20 | 1990 | Active |
| Pacific Horizon Homes | B | 2005 | Active |
| Pacific MH Construction Inc | B + C47 | 2002 | Active |
| Pacific Utility Installation Inc | A, B + C10 | 1997 | Active |
| Painting Unlimited Inc | B + C33 | 1993 | Active |
| Pardee Homes | B | 1968 | Active |
| Patagonia Builders Inc | B | 2022 | Active |
| PCM LLC | B | 2024 | Active |
| Petrotechs | A + HAZ | 2005 | Active |
| Plumbing Concepts Inc | B + C36 | 1985 | Active |
| Pool Guy Services Inc | B + C53, D35 | 1997 | Active |
| Portrait Construction Inc | B | 2012 | Active |
| Precision Water & Restoration | B + C36 | 2008 | Active |
| Premier Broadband Services Inc | A + C7, D09 | 2016 | Active |
| Prestige Concrete Company | A, B + C8, C12, C32 | 2003 | Active |
| Prestige Contracting Services Inc | B + C39 | 2024 | Active |
| Pro Building Concepts Inc | B | 2018 | Active |
| Pronan Construction LLC | B | 2009 | Active |