| Joe Gwerder G C | Joe Gwerder G C | — | (530) 601 0000 | GC, remodel, ADU | Woodland · Yolo County | — | — |
| Joe Lucas Welding | Joe Lucas Welding | — | (916) 856 0214 | Other | West Sacramento · Yolo County | — | — |
| Joel Bidinger | Joel Bidinger | — | (916) 410 3867 | Electricians | Clarksburg · Yolo County | — | — |
| John Aragon | John Aragon | — | (530) 312 8545 | Electricians | Woodland · Yolo County | — | — |
| John Billsingley | John Billsingley | — | (916) 450 9129 | GC, remodel, ADU | Clarksburg · Yolo County | — | — |
| John Brann Concrete | John Brann Concrete | — | (707) 494 0256 | Other | Knights Landing · Yolo County | — | — |
| John Cunningham Electric | John Paul Cunningham | — | (415) 359 8735 | Electricians | Davis · Yolo County | — | — |
| John Dustin Phillips | John Dustin Phillips | — | (530) 723 8812 | Electricians | Woodland · Yolo County | — | — |
| John E Vanderpool | John E Vanderpool | — | (530) 393 6547 | GC, remodel, ADU | Winters · Yolo County | — | — |
| John Frank Minney | John Frank Minney | — | (530) 908 1155 | GC, remodel, ADU | Woodland · Yolo County | — | — |
| John Leeman Painting And Wood Finishing | John Daniel Leeman | — | (530) 723 8063 | Windows, patio, painters | Woodland · Yolo County | — | — |
| John M Simmons Construction | John Martin Simmons | — | (530) 753 5638 | GC, remodel, ADU | Davis · Yolo County | — | — |
| John P Sanders Construction | John Paul Sanders | — | (530) 574 0881 | GC, remodel, ADU | Woodland · Yolo County | — | — |
| John Torres Construction Of California | John Vargas Torres | — | (916) 869 0164 | GC, remodel, ADU | Winters · Yolo County | — | — |
| Johnny Douthit Plumbing | Johnny Douthit Plumbing | — | (707) 580 2727 | Other | Winters · Yolo County | — | — |
| Johnson Home And Landscape | Johnson Home And Landscape | — | (530) 219 9011 | GC, remodel, ADU | Woodland · Yolo County | — | — |
| Jones X 3 Landscape | Jones X 3 Landscape | — | (530) 383 6682 | Windows, patio, painters | Woodland · Yolo County | — | — |
| Joseph F La Boffa | Joseph F La Boffa | — | (707) 761 7225 | GC, remodel, ADU | Woodland · Yolo County | — | — |
| Jrb Construction | Jose Antonio Rodrigues Bravo | rbergeron@jrb-construction.com | (530) 848 2393 | GC, remodel, ADU | Dunnigan · Yolo County | — | — |
| Jrcc Construction | Jaime Jr Rodarte | — | (530) 979 1753 | GC, remodel, ADU | Winters · Yolo County | — | — |
| Juggernaut Electrical | James Oliver Stevenson | — | (209) 244 2411 | Electricians | West Sacramento · Yolo County | — | — |
| K B H Construction INC | Civirjic Vitali | — | (916) 388 4024 | GC, remodel, ADU | West Sacramento · Yolo County | — | — |
| K O Construction INC | Joseph Edward Ogando | — | (530) 795 3816 | Other | Winters · Yolo County | — | — |
| K O Construction Rentals INC | Joseph Edward Ogando | — | (530) 795 3816 | GC, remodel, ADU | Winters · Yolo County | — | — |
| K O Underground Construction INC | Joseph Edward Ogando | — | (530) 795 3816 | Other | Winters · Yolo County | — | — |
| K Shahan Construction | Kevin Delene Shahan | — | (530) 219 3038 | GC, remodel, ADU | Dunnigan · Yolo County | — | — |
| Kelly Kooling INC | Gustavo Cruz | kellykooling1@gmail.com | (530) 908 6292 | HVAC | Woodland · Yolo County | — | — |
| Kennard Construction Management INC | Kevin Wayne Kennard | — | (707) 210 4691 | GC, remodel, ADU | Winters · Yolo County | — | — |
| Kent Arborist Services | John Asher Kent | — | (916) 868 8509 | Tree | Davis · Yolo County | — | — |
| Kessler Built LLC | Ian Kingsley Kessler | — | (530) 867 6349 | GC, remodel, ADU | Woodland · Yolo County | — | — |
| Kevin's Painting Const A Partnership | See Singh | — | (916) 416 5872 | Windows, patio, painters | West Sacramento · Yolo County | — | — |
| Key Painting INC | Keylon Nohe Lopez Campos | — | (650) 679 2974 | Windows, patio, painters | Woodland · Yolo County | — | — |
| Kitchen And Bath Pros | Kitchen And Bath Pros | — | (530) 383 0732 | GC, remodel, ADU | Woodland · Yolo County | — | — |
| Klein Flooring | Klein Flooring | — | (530) 304 8942 | Other | Davis · Yolo County | — | — |
| Knightworks Electric | Stephen John Knight | — | (530) 753 8913 | Electricians | Davis · Yolo County | — | — |
| Knn Flooring Corp | Peter Vakulich | — | (916) 476 7287 | Other | West Sacramento · Yolo County | — | — |
| Koi Enterprise | Koi Enterprise | — | (916) 373 0111 | Windows, patio, painters | West Sacramento · Yolo County | — | — |
| Kontokanis Electric | George Immanual Kontokanis | — | (916) 203 7271 | Electricians | West Sacramento · Yolo County | — | — |
| Kris Mircetich Painting | Kris Mircetich Painting | — | (530) 220 6885 | Windows, patio, painters | Davis · Yolo County | — | — |
| Kujala Construction INC | Kimmo Kalevi Kujala | — | (530) 219 5027 | GC, remodel, ADU | Woodland · Yolo County | — | — |