| Gb Heating And Air Conditioning INC | Grubesic Boris | — | (925) 766 9992 | HVAC | Pacheco · Contra Costa County | — | — |
| Gbwf LLC | Grant Alexander Burger | — | (541) 217 4606 | Other | El Cerrito · Contra Costa County | — | — |
| Geek Bay Construction | Gabriel Alejandro Gutierrez | gabriel@geekbayconstruction.com | (925) 381 9733 | GC, remodel, ADU | Antioch · Contra Costa County | — | — |
| Gehl Design / Build | Gehl Design / Build | info@gehldesignbuild.com | (510) 812 1039 | GC, remodel, ADU | Kensington · Contra Costa County | — | — |
| Gehrke INC DBA Horizon Plumbing | Timothy Frederick Gehrke | — | (925) 200 3760 | Other | Concord · Contra Costa County | — | — |
| Gem Builders | Gem Builders | — | (925) 828 9020 | GC, remodel, ADU | Danville · Contra Costa County | — | — |
| Gem Concrete Polishing LLC | Amy Baskin Havea | — | (925) 888 8333 | Other | Pleasant Hill · Contra Costa County | — | — |
| Gemini Construction Group LLC | Ashk Ryan Naraghi | — | (925) 250 6767 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| Gemini Distributors | Gemini Distributors | — | (213) 999 2864 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| Gems Environmental Management Services INC | Richard Edward Camacho | — | (925) 671 6822 | Windows, patio, painters | Concord · Contra Costa County | — | — |
| Gen3 Construction | David Warren Harrison | — | (925) 487 6945 | GC, remodel, ADU | Pittsburg · Contra Costa County | — | — |
| Genaro S Construction | Saldana Gonzalez Genaro | info@genarosconstruction.com | (925) 848 5712 | GC, remodel, ADU | Oakley · Contra Costa County | — | — |
| Gendun Choephel Electric | Choephel Gendun | — | (415) 290 5769 | Electricians | Richmond · Contra Costa County | — | — |
| Gene Catania Construction | Gene George Catania | — | (925) 497 3636 | Other roofers | Concord · Contra Costa County | — | — |
| General B Construction Specialist | Carlos Humberto Ramos | — | (510) 786 8327 | GC, remodel, ADU | Antioch · Contra Costa County | — | — |
| General Contractor & Remodeling | Bay Arbor | General Contractor & Remodeling | Bay Arbor | — | (925) 481-3885 | GC, remodel, ADU | Martinez · Contra Costa County | — | — |
| General Home Care | General Home Care | — | (925) 383 3960 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| General HVAC Electric | Petru Popov | — | (415) 834 8700 | HVAC | Pinole · Contra Costa County | — | — |
| Generational Garage Doors | Generational Garage Doors | — | (925) 316 8384 | Other | Martinez · Contra Costa County | — | — |
| Genesis Landscape INC | Mari Amanda Mc Call | — | (925) 687 7043 | Windows, patio, painters | Brentwood · Contra Costa County | — | — |
| Genesis Painting LLC | Ramiro Ernesto Castaneda | — | (510) 956 8349 | Windows, patio, painters | Richmond · Contra Costa County | — | — |
| Genish Garage Door INC | Tomer Solomon | info@genishgaragedoor.com | (818) 675 1184 | Other | Walnut Creek · Contra Costa County | — | — |
| Gentile Construction INC | Aaron Joseph Gentile | jgentile@gentileconstruction.com | (925) 397 3787 | GC, remodel, ADU | Danville · Contra Costa County | — | — |
| Gentry Construction | Dwight Earl Gentry | — | (925) 787 1659 | GC, remodel, ADU | Oakley · Contra Costa County | — | — |
| Genuine Drywall Contractors | Gursharan Singh Talwar | — | (510) 460 0022 | GC, remodel, ADU | Hercules · Contra Costa County | — | — |
| Genxpro Heating & Air Conditioning INC | Luis Vargas Marin | — | (925) 505 8398 | HVAC | Antioch · Contra Costa County | — | — |
| Geo - Tech Security INC | George Albert Iaconis | — | (925) 427 1111 | Electricians | Pittsburg · Contra Costa County | — | — |
| Geo's Pool Company | Jaime Geovanny Vasquez Garcia | contact@geospool.com | (925) 234 8087 | Pool | Concord · Contra Costa County | — | — |
| Geoghegan Homes Incorporated DBA Peralta Construction | Patrick Edmond Geoghegan | — | (510) 502 7405 | GC, remodel, ADU | Orinda · Contra Costa County | — | — |
| George Ed Vazquez | George Ed Vazquez | — | (510) 719 3165 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| George H Seligman | George H Seligman | — | (925) 499 9118 | Electricians | Oakley · Contra Costa County | — | — |
| George Irving Painting | George Irving Painting | — | (925) 330 5649 | Windows, patio, painters | Walnut Creek · Contra Costa County | — | — |
| George Stephen Weston | George Stephen Weston | — | (925) 300 5910 | GC, remodel, ADU | Walnut Creek · Contra Costa County | — | — |
| George's Flooring Corp | Jorge Luis Gutierrez Roiz | — | (415) 286 4062 | Other | San Pablo · Contra Costa County | — | — |
| Georges Tile Company | George Loyd | — | (925) 285 4397 | Other | Walnut Creek · Contra Costa County | — | — |
| Geostructural Engineering INC | Andre Stephen Hawks | — | (707) 322 3507 | Other | Pleasant Hill · Contra Costa County | — | — |
| Gerald Berry Plumbing | Gerald Berry Plumbing | — | (510) 233 3444 | Other | San Pablo · Contra Costa County | — | — |
| Gerardo A Valenzuela DBA Valenz Painting | Valenz Painting | — | (925) 234 1626 | Windows, patio, painters | Brentwood · Contra Costa County | — | — |
| Gerrard David Electric | David Rollan Gerrard | — | (510) 502 4687 | Electricians | Kensington · Contra Costa County | — | — |
| Get It Done Demolition | Get It Done Demolition | — | (925) 914 0164 | Other | Concord · Contra Costa County | — | — |