| James Starrett Enterprises | James Starrett Riley | — | (530) 205 7701 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| Janakes Electric | Jeffery James Janakes | — | (650) 333 2527 | Electricians | Penn Valley · Nevada County | — | — |
| Jason Kemp Electric | Jason Richard Kemp | — | (530) 272 5983 | Electricians | Grass Valley · Nevada County | — | — |
| Jason Murl Gilliam Painting | Jason Murl Gilliam Painting | — | (530) 559 7255 | Windows, patio, painters | Grass Valley · Nevada County | — | — |
| Jbm Construction | Jonathan Ben Morrill | — | (530) 613 5541 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| Jdw Welding LLC | John David Williams | — | (916) 806 4507 | Other | Grass Valley · Nevada County | — | — |
| Jeff Alaways Construction | Dwight Jeffrey Alaways | — | (530) 277 9873 | GC, remodel, ADU | Nevada City · Nevada County | — | — |
| Jeff Duncan Drywall | Jeff Duncan Drywall | — | (530) 906 3904 | Other | Rough And Ready · Nevada County | — | — |
| Jeff Fallow Construction | Jeffrey Ardell Fallow | — | (530) 582 8862 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| Jeff Hagar Painting | Jeff Hagar Painting | — | (530) 320 5359 | Windows, patio, painters | Grass Valley · Nevada County | — | — |
| Jeffrey Karwowski | Jeffrey Karwowski | — | (530) 205 6397 | Other | Grass Valley · Nevada County | — | — |
| Jensen's Tree Care | Jensen's Tree Care | — | (530) 802 4544 | Tree | Penn Valley · Nevada County | — | — |
| Jeremy Purdy Construction INC | Jeremy Allen Purdy | — | (530) 448 1030 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| Jeremy W Robinson Construction | Jeremy William Robinson | — | (530) 559 0315 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| Jerry Van Heeringen | Jerry Van Heeringen | — | (530) 913 5709 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| Jevons Plumbing | Jevons Plumbing | — | (831) 234 3603 | Other | Nevada City · Nevada County | — | — |
| Jim Bilinski | Jim Bilinski | — | (530) 710 4147 | Windows, patio, painters | Penn Valley · Nevada County | — | — |
| Jim Faletti Construction | Jimmy Lee Ii Faletti | — | (530) 575 0986 | GC, remodel, ADU | Nevada City · Nevada County | — | — |
| Jim Harlicker Electric | James William Harlicker | — | (530) 477 8424 | Electricians | Penn Valley · Nevada County | — | — |
| Jim Juvinall General Contractor | Jim Juvinall General Contractor | — | (831) 277 3595 | GC, remodel, ADU | Nevada City · Nevada County | — | — |
| Jim Meadows Construction INC | James Matthew Meadows | — | (530) 559 5850 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| Jim Norman's Trees Unlimited INC | James Everett Iii Norman | — | (530) 271 5536 | Tree | Grass Valley · Nevada County | — | — |
| Jim Romero Construction | James Edward Romero | info@jimromeroconstruction.com | (530) 559 9149 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| Jim Sontag Construction | James Anthony Sontag | — | (530) 559 5746 | GC, remodel, ADU | North San Juan · Nevada County | — | — |
| Jla Construction INC | Jorge Alberto Alcaraz Lopez | — | (530) 386 3197 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| Jlb Construction | Jared Lawerence Bringolf | info@jlb-construction.com | (530) 913 0261 | GC, remodel, ADU | Rough And Ready · Nevada County | — | — |
| Jlq General Build | Jlq General Build | info@jlqgeneralbuildllc.com | (530) 446 1428 | Other roofers | Grass Valley · Nevada County | — | — |
| Jms Builders | Jon Michael Simpson | — | (530) 913 4366 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| Jnl Engineering | Noel Richard High | — | (530) 329 2981 | Other | Grass Valley · Nevada County | — | — |
| Joe Day Construction | Joseph Carlton Day | — | (530) 798 9903 | GC, remodel, ADU | Nevada City · Nevada County | — | — |
| Joe Gardens | Joseph Edward Ii Coberly | — | (530) 575 9498 | Windows, patio, painters | Grass Valley · Nevada County | — | — |
| Joe Putzel Wood Floors | Joe Putzel Wood Floors | — | (530) 320 2823 | Other | Grass Valley · Nevada County | — | — |
| Johansen Masonry INC | Paul Kristian Johansen | contact@sansoxygen.com | (530) 587 2259 | Other | Truckee · Nevada County | — | — |
| John A Miller Const | John A Miller Const | — | (530) 913 6128 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| John Butterfield Construction | John James Butterfield | — | (530) 265 5122 | GC, remodel, ADU | Nevada City · Nevada County | — | — |
| John Campbell Painting | John Campbell Painting | — | (530) 292 1251 | Windows, patio, painters | Nevada City · Nevada County | — | — |
| John Darrow Construction | John Leslie Darrow | — | (530) 432 0533 | GC, remodel, ADU | Penn Valley · Nevada County | — | — |
| John Greenside Construction | John Richard Greenside | — | (530) 913 2838 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| John J Nash Const | John J Nash Const | — | (775) 745 5720 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| John L Washburn Painting | John L Washburn Painting | — | (626) 429 4357 | Windows, patio, painters | Grass Valley · Nevada County | — | — |