| Blue Wood Construction Inc | B + C7, C10, C36 | 2015 | Active |
| BMJ Construction Inc | B | 2023 | Active |
| BMK Construction Corporation | B | 2021 | Active |
| BNTZ Construction Inc | B | 2026 | Active |
| Boaz Mor Design And Construction | B | 2009 | Active |
| Bold Construction | B | 2024 | Active |
| Boom City Builders LLC | B | 2016 | Active |
| Borak Design And Construction | B | 2026 | Active |
| Boulder Crest Construction Inc | B | 2026 | Active |
| Boylan John Engineering Inc | A | 2023 | Active |
| Bradford Construction Inc | B | 2003 | Active |
| Bradshaw Group Inc | B | 2025 | Active |
| Bravo Made Construction Inc | B | 2024 | Active |
| Breckenridge Ron Enterprises Inc | A + HAZ | 2000 | Active |
| Brennan John Company Inc | B | 1965 | Active |
| Brennan Stronghold Construction Inc | B + HAZ | 2011 | Active |
| Brighter Legacy Builders Inc | B | 2019 | Active |
| Brilliant Jobs Construction LLC | B + C10, C36 | 2023 | Active |
| Brinkerhoff Construction Inc | B | 1990 | Active |
| Brotherhu Builders Construction Inc | B | 2023 | Active |
| Brothers Lui Inc | B + C10 | 2006 | Active |
| Brunner K & Associates Inc | B | 1970 | Active |
| Budget Blinds Of San Francisco North | B + C10, C36, D52 | 1991 | Active |
| Buena Vista Builders Inc | B | 1996 | Active |
| Buhler Commercial | A, B | 2015 | Active |
| Buhler Construction Company Inc | B | 2012 | Renew by Nov 30, 2026 |
| Build Atlas | B + C39 | 2024 | Active |
| Build For Life Construction | A, B + C10, C36 | 2022 | Active |
| Build Group Inc | A, B | 2007 | Active |
| Build SF Inc | B | 2019 | Active |
| Buildcorp Inc | A, B + C10 | 2020 | Active |
| Builders Coordination Inc | A + C10, C36 | 2024 | Active |
| Building Construction Express | B | 2016 | Active |
| Building Efficiency Inc | B + ASB, C10, C20 +1 | 2010 | Active |
| Buildsingular JV | B | 2024 | Active |
| Built Steady Inc | B + C33, C36 | 2026 | Active |
| Bullard's Heating & Air Inc | B + C20, C36 | 1996 | Active |
| Burdell Construction Inc | B | 2009 | Active |
| Burnham C H Inc | B | 2011 | Active |
| BZ And BZ Corporation Inc | B | 2024 | Active |
| C & H Home Construction | B | 2015 | Active |
| C & L Builders Inc | B | 2005 | Active |
| C & M General Contractor | B | 1986 | Active |
| C C F Construction LLC | B | 2022 | Active |
| C C I Commercial Construction & Improvements Inc | B | 2013 | Active |
| C L & Y Construction Inc | B | 2007 | Active |
| C M Construction Company | A, B + C36, C51 | 1987 | Active |
| C Max Construction Inc | B | 2023 | Active |
| C N A Construction Inc | B | 1997 | Active |
| C P G Construction Inc | B | 2016 | Active |
| C Plus E Construction Inc | B | 2025 | Active |
| C S I Customer Service General Contracting Inc | A, B + C51 | 1986 | Renew by Dec 31, 2026 |
| C T B Construction Inc | B | 1995 | Active |
| C3pr Inc | A, B + C31, C32 | 2023 | Active |
| Cabo Building Repairs & Maintenance Inc | B | 2021 | Active |
| Cahill - Nibbi Joint Venture | B | 2009 | Active |
| Cahill - Nibbi Joint Ventures | B | 2017 | Active |
| Cahill - TSM Joint Venture | B | 2016 | Active |
| Cahill Contractors Inc | A, B | 1974 | Active |
| Cahill Contractors LLC | A, B + C8 | 2016 | Active |
| Cahill Guzman Construction Group JV | B | 2016 | Active |
| Cahill Light Frame Joint Venture | A, B | 2018 | Active |
| Cahill-Pilot Joint Venture | A, B | 2025 | Active |
| Cahill-Singular Joint Venture | A, B + C8 | 2025 | Active |
| Cai Construction | B + C36 | 2021 | Active |
| Caicon LLC | B | 2025 | Active |
| Cairn Construction Company Inc | B | 1998 | Active |
| Cal - C A D E Construction Inc | B | 2009 | Active |
| Cal Am Construction Inc | B + C10, C36 | 2006 | Active |
| Cal Builder Inc | B | 2024 | Active |
| Cal Landmark Electric And Construction Inc | B + C10 | 2017 | Active |
| Cal State Constructors Inc | A, B | 2006 | Active |
| California Development & Renovation | B + C33, C39 | 2002 | Renew by Dec 31, 2026 |
| California Energy Solutions | B + C10 | 2010 | Active |
| California Home Improvement Solutions Inc | B + C17, D52 | 2004 | Active |
| Camber Operating Company LLC | B | 2026 | Active |
| Cameron Home Builders | B | 2023 | Active |
| Canning Electric Inc | A, B + C10 | 1995 | Active |
| Canseco Construction Corp | B | 2022 | Renew by Dec 31, 2026 |
| Capomastro Group A California Corporation | B | 2006 | Renew by Nov 30, 2026 |
| Cardea Building Co | B + C6 | 2005 | Active |
| Carmel Construction West LLC | B | 2020 | Active |
| Carnhill Construction | B | 2025 | Active |
| Casement Construction Inc | B | 1996 | Active |
| Castillo Grande Inc | B | 2025 | Active |
| Castle Company | B + D41 | 2011 | Active |
| Caymen Construction Corp | B | 2009 | Active |
| Cazadoro Construction | A | 2015 | Active |
| CBS Smart Construction Inc | B | 2025 | Active |
| CC Renovation Expert | B2 | 2026 | Active |
| Ccesf | A | 2025 | Active |
| CD Remodeling Inc | B | 2023 | Active |
| Cdim Engineering Inc | A + HAZ | 2016 | Active |
| CDR Construction Group Inc | B | 2008 | Active |
| Centoni Restoration And Development Inc | B | 2009 | Active |
| Central Convalescent Homes Inc | B + C10, C16, C36 | 2013 | Active |
| Chalk Line LLC | B | 2025 | Active |
| Chao Builders Group | B | 2026 | Active |
| Cheong Yiu Construction Co Inc | B | 1993 | Active |
| CHL Construction Inc | B | 2011 | Active |