| Fortify Restoration | Atar Barkai | — | (831) 444 5824 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| Forum Plastering | Forum Plastering | ericangeles@forumplastering.com | (510) 414 7865 | Other | San Pablo · Contra Costa County | — | — |
| Fos Electric INC | Steve Vyacheslav Tsvetkov | info@foselectric.com | (510) 219 6265 | Electricians | Pinole · Contra Costa County | — | — |
| Fosbery General Building Contractor | Fosbery General Building Contractor | — | (925) 588 8914 | GC, remodel, ADU | Clayton · Contra Costa County | — | — |
| Foster Construction INC | Kyle James Foster | interested@domainmarket.com | (925) 323 1256 | GC, remodel, ADU | Pleasant Hill · Contra Costa County | — | — |
| Foster Development | Foster Development | — | (925) 408 5110 | GC, remodel, ADU | Danville · Contra Costa County | — | — |
| Foundation Constructors INC | Brook Edward Serafino | — | (925) 754 6633 | Other | Oakley · Contra Costa County | — | — |
| Foundation Pile INC | John Darrell Honaker | — | (925) 754 6633 | Other | Oakley · Contra Costa County | — | — |
| Foundation Power INC | Brook Edward Serafino | — | (925) 754 6633 | Other | Oakley · Contra Costa County | — | — |
| Foundation Soil Stabilization INC | Eric Daniel Quiles | — | (925) 494 0300 | Other | Pleasant Hill · Contra Costa County | — | — |
| Foundry Builder | Foundry Builder | — | (925) 784 3535 | GC, remodel, ADU | Discovery Bay · Contra Costa County | — | — |
| Fountain Blue Pool Services LLC | Richard Enon Jr Striplin | contact@fountainbluepoolservices.com | (925) 339 0408 | Pool | Concord · Contra Costa County | — | — |
| Four Brothers | Hun Young Kim | — | (925) 719 7084 | GC, remodel, ADU | San Ramon · Contra Costa County | — | — |
| Fourth Generation Tile Co | John Russell Jr Schueller | — | (925) 370 6936 | Other | Martinez · Contra Costa County | — | — |
| Foy Electric | David Francis Foy | — | (925) 595 4024 | Electricians | Concord · Contra Costa County | — | — |
| Fpmfls LLC | Geary Donald Tsutsui | — | (925) 397 3473 | Electricians | Martinez · Contra Costa County | — | — |
| Fr Ruiz INC | Rico-ruiz Fabian | — | (925) 787 2819 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| Frame Craft Drywall INC | Fernando Rios | — | (925) 206 8108 | Other | Concord · Contra Costa County | — | — |
| Francesco Toce | Francesco Toce | — | (415) 307 1341 | Other | Concord · Contra Costa County | — | — |
| Franchi Electric | Gleber Fabiano Franchi | — | (510) 224 5996 | Electricians | Rodeo · Contra Costa County | — | — |
| Francis Robert Greguras Jr | Francis Robert Greguras Jr | — | (925) 899 2167 | Other | Brentwood · Contra Costa County | — | — |
| Francisco Javier Penunuri | Francisco Javier Penunuri | — | (415) 272 5330 | Other | Richmond · Contra Costa County | — | — |
| Francisco Landscaping & Gardening | Francisco Landscaping & Gardening | — | (415) 488 7159 | Windows, patio, painters | Richmond · Contra Costa County | — | — |
| Francisco R Vera | Francisco R Vera | — | (760) 529 3613 | Other | Moraga · Contra Costa County | — | — |
| Francisco's Carpet Service | Arriaga Francisco | — | (925) 584 0523 | Other | Oakley · Contra Costa County | — | — |
| Franco Top Services Construction | Franco Amaru Martinez Fonte | — | (407) 807 3522 | GC, remodel, ADU | El Sobrante · Contra Costa County | — | — |
| Franco's Floors | Franco's Floors | info@francosfloors.com | (925) 339 0144 | Other | Brentwood · Contra Costa County | — | — |
| Frank Salazar DBA F S Plumbing | F S Plumbing | — | (925) 595 3962 | Other | Martinez · Contra Costa County | — | — |
| Frank's Garage Doors | Frank's Garage Doors | — | (925) 625 6256 | Other | Oakley · Contra Costa County | — | — |
| Frankie's Plumbing | Cano Cortez | — | (925) 286 5114 | Other | Martinez · Contra Costa County | — | — |
| Franko Construction Company | Daniel Steven Franko | — | (925) 989 0521 | GC, remodel, ADU | Walnut Creek · Contra Costa County | — | — |
| Freas Plastering Company INC | Donald Raymond Freas | contact@freasplastering.com | (925) 676 8964 | Other | Concord · Contra Costa County | — | — |
| Fred's Fast Plumbing | Fred's Fast Plumbing | — | (925) 219 2709 | GC, remodel, ADU | Oakley · Contra Costa County | — | — |
| Fred's Floor Covering | Fred's Floor Covering | — | (925) 890 7082 | Other | Concord · Contra Costa County | — | — |
| Freddy Construction | Manuel Frederick Jr Najera | — | (925) 360 4251 | GC, remodel, ADU | Martinez · Contra Costa County | — | — |
| Fredimar Handyman INC | Travis Lee Johnson | — | (925) 595 1927 | GC, remodel, ADU | Pittsburg · Contra Costa County | — | — |
| Fredy's Roofing INC | Udave Meza Fredy | — | (925) 565 0747 | Other roofers | Antioch · Contra Costa County | — | — |
| Freedom Heating And Air Conditioning | Freedom Heating And Air Conditioning | — | (925) 446 1590 | HVAC | Martinez · Contra Costa County | — | — |
| Freeman Roofing | Joseph Michael Freeman | — | (925) 876 9011 | Other roofers | Pittsburg · Contra Costa County | — | — |
| Freeman's Heating Air Conditioning & Electrical Services | Llewellyn Everton Freeman | — | (925) 212 3470 | HVAC | Walnut Creek · Contra Costa County | — | — |