| Jg Landscaping | Jg Landscaping | — | (707) 333 1937 | Windows, patio, painters | Vallejo · Solano County | — | — |
| Jg Landscaping | Jg Landscaping | — | (707) 592 2444 | Windows, patio, painters | Vacaville · Solano County | — | — |
| Jg Schulte Electric | Jason Gabriel Schulte | — | (925) 565 1569 | Electricians | Vallejo · Solano County | — | — |
| Jhd Construction | Michael Ian Gough | — | (916) 205 2257 | GC, remodel, ADU | Benicia · Solano County | — | — |
| Jim Garton Steel Construction INC | James Thomas Garton | — | (707) 688 2811 | Other | Vacaville · Solano County | — | — |
| Jim Wilson Concrete | Jim Wilson Concrete | — | (707) 695 5525 | Other | Vacaville · Solano County | — | — |
| Jiunti INC | Peter Ronald Jiunti | — | (415) 559 3280 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Jjr Flooring | Jjr Flooring | — | (707) 362 6228 | Other | Vacaville · Solano County | — | — |
| Jm Integration LLC | Jack Jay Miller | support@jmintegration.com | (707) 365 1843 | Electricians | Vacaville · Solano County | — | — |
| Joe Ramblas | Joe Ramblas | — | (415) 309 2726 | GC, remodel, ADU | Vallejo · Solano County | — | — |
| Joe Tenorio Grading & Paving | Joe Tenorio Grading & Paving | — | (707) 712 9263 | Other | Suisun · Solano County | — | — |
| Joe Thurin Painting | Joe Thurin Painting | — | (707) 246 5419 | Windows, patio, painters | Benicia · Solano County | — | — |
| John C Wignall | John C Wignall | — | (707) 372 0560 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| John Crisafulli | John Crisafulli | — | (707) 689 3457 | Other | Vacaville · Solano County | — | — |
| John Hess Landscape Construction | John Lawrence Hess | — | (707) 628 2204 | Windows, patio, painters | Vacaville · Solano County | — | — |
| John King Electric | John Diego King | — | (707) 446 9735 | Electricians | Vacaville · Solano County | — | — |
| John L Ralls Construction | John Leroy Ralls | — | (707) 429 8973 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| John Laverty Construction | John Francis Laverty | — | (707) 745 1660 | GC, remodel, ADU | Benicia · Solano County | — | — |
| John M Olson | John M Olson | — | (707) 746 8800 | Electricians | Benicia · Solano County | — | — |
| John Scott Construction & Consulting | John Douglass Scott | — | (415) 716 7848 | GC, remodel, ADU | Vallejo · Solano County | — | — |
| John's Backflow Tech & Service | John Craig Barber | — | (707) 205 9397 | Other | Vacaville · Solano County | — | — |
| Johnson Acoustics INC | Keith O'bryan Johnson | — | (707) 889 8510 | Other | Vacaville · Solano County | — | — |
| Johnson Custom Garage Door Co | Sara Rene Johnson | — | (707) 421 2300 | Other | Suisun City · Solano County | — | — |
| Jon Lincoln Construction | Jonathon Robert Lincoln | — | (707) 363 7800 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Jones Construction Company | Robert Louis Jones | — | (707) 290 6381 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Jordan Benning Construction | Jordan Leigh Benning | — | (707) 425 2200 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Jorge Andrade Salvador | Jorge Andrade Salvador | — | (510) 255 9975 | Other | Vallejo · Solano County | — | — |
| Jose Ernesto Reyes Fuentes | Jose Ernesto Reyes Fuentes | — | (707) 553 3436 | Electricians | Vallejo · Solano County | — | — |
| Joseph Moralde Pampliega | Joseph Moralde Pampliega | — | (510) 232 5136 | Other | Vallejo · Solano County | — | — |
| Jovani's Plumbing INC | Jovani Madera Figueroa | — | (707) 689 2230 | Other | Vacaville · Solano County | — | — |
| Jp Tile | Jp Tile | — | (707) 287 6519 | Other | Vacaville · Solano County | — | — |
| Jpr Pavers | Jpr Pavers | — | (510) 672 7570 | Other | Fairfield · Solano County | — | — |
| Jr Construction | Jad Raja Souki | — | (707) 718 8449 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Js Erickson Electric | Jeffrey Scott Erickson | — | (707) 299 8721 | Electricians | Vallejo · Solano County | — | — |
| Jsg Remodeling | Josue Sanchez | — | (415) 419 6673 | GC, remodel, ADU | Vallejo · Solano County | — | — |
| Jsl Landscaping & Maintenance INC | James Scott Ladd | — | (707) 426 4738 | Windows, patio, painters | Fairfield · Solano County | — | — |
| Jt Landscaping | Thuy Dinh Tran | — | (510) 828 0300 | Windows, patio, painters | Vallejo · Solano County | — | — |
| Jta Builders INC | Aguilar Jorge Tellez | — | (510) 356 8935 | GC, remodel, ADU | Vallejo · Solano County | — | — |
| Just In Time Home Renovations LLC | Justin Garrett Smithson | — | (707) 592 4188 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Just Pave It | Shawn Wayne Stanley | — | (925) 566 4851 | Other | Vacaville · Solano County | — | — |