| Martin's Bay Area Construction | B | 2017 | Active |
| Master Roofing Company | B + C10, C39 | 2008 | Active |
| Mauck Sheet Metal | B + C20, C23, C43 | 1989 | Active |
| Mayco Commercial Construction | B | 2017 | Renew by Dec 31, 2026 |
| MC Guire And Hester | A, B + C21, C27, C31 +1 | 1947 | Active |
| McDonald Ar Builders Inc | B | 2019 | Active |
| McGuire And Hester - Power Engineering Construction Company | A, B + C21, C27, C31 +1 | 2024 | Renew by Nov 30, 2026 |
| Mec Custom Builders Inc | B | 2017 | Active |
| Medrano Construction Corp | B | 2009 | Active |
| Metal Building Company | B + C43, C51, D28 | 1982 | Active |
| MF General Construction & Remodeling | B2 | 2025 | Active |
| Millers Builders Inc | B | 2025 | Active |
| Minka Artisans LLC | B | 2025 | Active |
| Miracle Playsystems Incorporated | B | 2026 | Active |
| Mireles Construction Inc | B | 2018 | Active |
| MN Builders | B | 1990 | Active |
| Monarch Mechanical | B + C20, C36, C43 | 1997 | Active |
| Montclair Construction & Structural Inc | B | 1993 | Active |
| Monterey And MWH Constructors, A Joint Venture | A + ASB, C16, C20 +1 | 2020 | Active |
| Monterey Mechanical Co | A, B + C4, C12, C16 +4 | 1980 | Active |
| Moore Construction & Remodel Inc | B + C33 | 2010 | Active |
| Moraes Construction Inc | B | 2016 | Active |
| Mosaic Construction | B | 2012 | Renew by Dec 31, 2026 |
| My Remodeling Group Inc | B | 2023 | Active |
| Native Soil Inc | A, B + C27 | 2018 | Active |
| Next Level Development LLC | B | 2020 | Renew by Dec 31, 2026 |
| Nextgen Remodeling & Construction Inc | B | 2026 | Active |
| Norcal Rock Inc | A + C21 | 2008 | Active |
| Norstar Construction | B | 2006 | Active |
| Northgate Environmental Management Inc | A + HAZ | 2000 | Renew by Dec 31, 2026 |
| Nuvation Design Builders | B | 2006 | Active |
| Oak General Construction Inc | B | 2026 | Active |
| Oak Park Construction | B | 2004 | Active |
| Oakal Construction Inc | B | 2026 | Active |
| Oakstead | B | 2025 | Active |
| Ocd Plan & Build Inc | B | 2025 | Active |
| Olczak Build | B | 2025 | Active |
| Omega Termite And Pest Control Inc | B | 1980 | Active |
| Orozcollective Construction Inc | B | 2022 | Active |
| Oscar Construction & Remodeling Inc | B | 2021 | Active |
| Otai Construction Inc | B | 2012 | Active |
| Over The Woodsman Builder Inc | B | 1996 | Active |
| Owow Construction LLC | B | 2021 | Active |
| P & D Environmental Inc | A + HAZ | 2007 | Active |
| P J Plumbing Inc | A, B + C8, C36, C42 | 2014 | Active |
| Pablo General Contractor DBMC | B | 2022 | Active |
| Pac Bay Environmental Services Inc | A, B + ASB, C21, HAZ | 2017 | Active |
| Pacific Estate Construction Group Inc | B | 2025 | Active |
| Pacific Trenchless Inc | A | 2000 | Active |
| Path Forward Partners Inc | A | 2019 | Active |
| Pearl Engineering And Construction | A, B | 1990 | Active |
| Pena's Construction Inc | B | 2003 | Active |
| Pink Hammer Builders Inc | B | 2026 | Active |
| Pinnacle Socal | B | 2026 | Active |
| Pipe Spy Inc | A + C36 | 1998 | Active |
| Planstarts Builder Inc | B | 2026 | Active |
| Planted Solar Inc | A | 2026 | Active |
| Platinum Home Builders Inc | B | 2020 | Active |
| Powers Construction | B | 2021 | Active |
| Precise Construction Builder Inc | B | 2012 | Active |
| Prestige Builders & Design | B | 2025 | Active |
| Process Engineers Inc | A + D21, D23 | 1983 | Active |
| Proven Management Inc | A, B | 1998 | Active |
| Pulido's General Construction Inc | B | 2020 | Active |
| Quality Control Construction | B | 2022 | Active |
| Quantum Energy Services & Technologies Inc | B + C10 | 2004 | Active |
| R F Contractors | B + C15 | 2015 | Active |
| R Perez General Contractor Inc | B | 2016 | Active |
| Ranks Construction LLC | B | 2024 | Active |
| Ray's Electric | A + C10 | 1993 | Active |
| Ready2servehandyman LLC | B | 2009 | Active |
| Rebuild Better Home Construction Inc | B | 2025 | Active |
| Redgwick Construction Co | A + HAZ | 1953 | Active |
| Redux C + D Inc | B | 2015 | Active |
| Redwood Grove Build Inc | B | 2026 | Active |
| Rei Build Up Construction Corp | A, B + C8, C51 | 2019 | Active |
| Residential Restoration Co | B | 2010 | Active |
| Restorcap LLC | A | 2025 | Active |
| Reunion Creative Inc | B | 2026 | Active |
| River Land Construction Inc | B | 2021 | Active |
| RMB Construction Group Inc | B | 2010 | Active |
| Rosas Brothers Construction | A | 2004 | Active |
| Roya Constructora Inc | B | 2025 | Active |
| Rudolph Commercial Interiors Inc | B | 1992 | Active |
| S & S Builder Inc | B | 2016 | Active |
| S & S Trucking | A | 2013 | Active |
| Salvi Development And Consulting LLC | B | 2024 | Active |
| Sarco Construction | B | 2006 | Active |
| Sazos Construction Inc | B | 2018 | Active |
| Scally Electric Inc | B + C10 | 1985 | Active |
| Seifert Engineering Inc | A, B + C10 | 2006 | Active |
| Service West Inc | B + D34 | 1989 | Active |
| Sewer Master Engineering Inc | A, B | 2006 | Active |
| Shada Build & Design Inc | B | 2013 | Active |
| Shalco Construction Co Inc | B + C9 | 1982 | Renew by Nov 30, 2026 |
| Shalom N Home Inc | B | 2025 | Active |
| Shedmania | B | 2020 | Active |
| Signature Development Group Inc | B | 2013 | Active |
| Sincere Home Installation & Construction LLC | B | 2014 | Active |
| Skybar Construction Inc | B + D41 | 2022 | Active |