| Luna Construction Company | A, B + C8 | 2011 | Active |
| Luth & Turley Inc | B + C15 | 1979 | Active |
| LZ Construction | B | 1987 | Active |
| M D G Construction | B | 2024 | Renew by Nov 30, 2026 |
| M P Construction | B | 2003 | Active |
| M Unique Construction Landscape Inc | B + C27 | 2026 | Active |
| Man General Engineering Inc | A, B | 2013 | Active |
| Mann Plumbing | B + C36 | 2009 | Active |
| Marcco Flood Restoration | B | 2013 | Active |
| Marquez Landscape And Maintenance Inc | B + C27 | 2019 | Active |
| MC Breaty Construction Corporation | B + C17 | 2005 | Active |
| McBreaty Windows & Doors | B + C17 | 1994 | Active |
| McKeever Inc | B + C6 | 2005 | Active |
| McMillin Contracting Services Inc | B | 2012 | Active |
| MDS Property Maintenance | B | 2016 | Active |
| Meram Construction Inc | B | 2020 | Active |
| Miltco Inc | B | 2004 | Active |
| Modern Construction Specialties Inc | B | 2013 | Active |
| Moreno General Construction Inc | B | 2022 | Active |
| Mr D's Construction Services Of San Diego Inc | B + C33 | 2013 | Active |
| Mullen Kirk Incorporated | B + C6 | 1982 | Renew by Nov 30, 2026 |
| N P S Construction | B | 2024 | Active |
| Neder R Construction Inc | B | 2009 | Active |
| Neema Engineering | A, B | 2025 | Active |
| Neema General Contracting | A, B + ASB, C10, HAZ | 2022 | Active |
| New Coast Contractors Inc | B | 1987 | Active |
| New Era Plumbing & Construction Inc | B + C36 | 2016 | Active |
| New Vision Building & Design | A, B + C8 | 2013 | Active |
| New West Investment Group Inc | B | 2003 | Active |
| Nielsen Builders Inc | B | 2012 | Active |
| Nuveau Homes | B2 | 2022 | Active |
| Olympia Services | B | 2018 | Active |
| Onyx Building Group Inc | B + C9, C35 | 2011 | Active |
| Optimal Waterproofing & Reconstruction | B + D06, D12 | 2020 | Active |
| Ortega's Construction Inc | B | 1999 | Active |
| P R Construction And Design Inc | B | 2023 | Active |
| Pacific Concrete & Engineering | A, B + C8 | 2017 | Active |
| Pacific Grading And Erosion Control Inc | A + HAZ | 2008 | Active |
| Pacific Patriot Engineering Inc | A | 2026 | Active |
| Pacific Refrigeration Inc | B + C20, C38 | 1972 | Active |
| Pacific Truss Inc | B | 2021 | Active |
| Papenhausen Construction Inc | B | 2016 | Active |
| Para Quality Construction Inc | B | 1991 | Active |
| Pasha Builders Inc | B | 2022 | Active |
| Perfect Fit Construction | B | 2025 | Active |
| Peterson Gary & Son Construction | B | 1996 | Active |
| Petra Arts Construction | B | 2021 | Active |
| Pinnick Inc | A | 1974 | Active |
| Pioneer Custom Glass Inc | B + C17 | 2007 | Active |
| Pioneer Grading & Excavation Inc | A | 2019 | Active |
| PK Handy Construction Inc | B | 2024 | Active |
| Plumbright Inc | B + C36 | 1986 | Active |
| Point Development Group Inc | B | 2006 | Active |
| Pollock Equipment Inc | A + C12 | 2004 | Active |
| Ponce Remodeling Inc | B2 | 2025 | Active |
| Poopbutt Inc | B | 2025 | Active |
| Prestige Prime Engineering | A | 2024 | Active |
| Primary General Inc | B | 2002 | Active |
| Pritchard Projects LLC | B | 2026 | Active |
| Pro Finish Painting Inc | B + C33 | 2007 | Active |
| Pro-Active Concrete Inc | A + C8 | 2017 | Active |
| Protokai General Construction Inc | B | 2022 | Active |
| Public Works Contractor Inc | A, B + C4, C20, C36 +1 | 1987 | Renew by Dec 31, 2026 |
| R & L Construction & Engineering | A | 2010 | Renew by Nov 30, 2026 |
| R D Engineering & Construction Inc | A, B + C8, C10, HAZ | 1990 | Active |
| R J R Construction Inc | B | 2008 | Renew by Dec 31, 2026 |
| R K C Construction Inc | B + C17, D03, D06 | 2004 | Active |
| R P Cable & Engineering | A | 2020 | Active |
| Ram Construction SD LLC | B | 2023 | Active |
| Ram Jack Pacific | A, B + C10, D12, D30 | 2015 | Active |
| Rand Engineering Incorporated | A | 2006 | Active |
| Rayco Specialties Inc | A, B | 2025 | Active |
| Razors Edge Grading And Excavation Inc | A + C12 | 2012 | Active |
| RDC Custom Builders Inc | B | 2026 | Active |
| React Construction Management Inc | B | 2018 | Active |
| Redfield's Inc | B | 1999 | Active |
| Redona Construction | B | 2026 | Active |
| Reed's Construction Inc | B | 2008 | Active |
| Rice Construction Group | B | 2026 | Active |
| RL Roofing And Solar | B + C10, C39, C46 | 1986 | Active |
| RML General Construction | B | 2025 | Active |
| Robcor Construction LLC | B | 2024 | Active |
| Roma Engineering & Construction Inc | A, B + C10 | 2011 | Active |
| Ropp Construction Inc | B | 2009 | Active |
| RPF Contracting Inc | B | 2025 | Active |
| Rt's Design And Construction | B | 2025 | Active |
| S A Framers Inc | B | 2002 | Active |
| S C Valley Engineering Inc | A | 1991 | Active |
| S D Concreators Inc | B + C8 | 2014 | Active |
| S D R Contracting Inc | B | 2004 | Active |
| S L United Construction Inc | B | 2016 | Renew by Dec 31, 2026 |
| S N S Building Services Inc | B | 2009 | Active |
| S&K Maintenance And General Construction LLC | B | 2024 | Active |
| Saad Bath & Shower LLC | B2 | 2025 | Active |
| Salazar Construction | B | 2010 | Active |
| San Diego Bay Electric | B + C10 | 2014 | Active |
| San Diego Beavers Inc | B | 2016 | Active |
| San Diego Door & Trim Inc | B | 2023 | Active |
| San Diego Footing Repair Inc | B | 2016 | Active |
| San Diego Outdoor Living Company Inc | B + C27 | 2011 | Active |