| J W Plumbing | J W Plumbing | — | (805) 444 5959 | Other | Thousand Oaks · Ventura County | — | — |
| J Weir Masterworks INC | Joshua Gene Weir | — | (406) 600 9019 | GC, remodel, ADU | Ventura · Ventura County | — | — |
| J Z S Construction INC | John Mark Zimpelman | — | (310) 924 4625 | GC, remodel, ADU | Oxnard · Ventura County | — | — |
| J&d Masonry INC | Jorge Rafael Hernandez | — | (805) 204 1710 | Other | Oxnard · Ventura County | — | — |
| J&t Engineering And Construction Company | Jerome Saul Contreras | — | (805) 390 1246 | GC, remodel, ADU | Camarillo · Ventura County | — | — |
| J-4 Construction | Jeffrey Larson Simonsgaard | — | (805) 217 6793 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| Jack E Mantor | Jack E Mantor | — | (805) 701 7271 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| Jack-n-jill Enterprises INC | Patrick Alexander Martinez | — | (805) 432 8009 | Other | Thousand Oaks · Ventura County | — | — |
| Jacks & Racks Low Voltage | Gregory Allen Devore | — | (707) 227 7391 | Other | Ventura · Ventura County | — | — |
| Jacksonia Corporation | John Michael Malouf | — | (805) 498 8300 | GC, remodel, ADU | Newbury Park · Ventura County | — | — |
| Jacobo Lath And Plastering | Arevalo Tomas Jacobo | — | (805) 512 3754 | Other | Oxnard · Ventura County | — | — |
| Jacobs Electric | Milo Gene Jacobs | — | (805) 498 9424 | Electricians | Newbury Park · Ventura County | — | — |
| Jade Construction Company | Ida Mary Dakessian | — | (323) 829 2407 | GC, remodel, ADU | Moorpark · Ventura County | — | — |
| Jaime Anaya | Jaime Anaya | — | (805) 630 5220 | Other | Moorpark · Ventura County | — | — |
| Jake Fornoff Electric DBA Jake Electric | Jacob Willis Fornoff | — | (805) 432 5749 | Electricians | Moorpark · Ventura County | — | — |
| Jake Stone Construction | Jacob Alan Stone | — | (805) 798 0568 | GC, remodel, ADU | Ojai · Ventura County | — | — |
| Jakk Heating And Air Conditioning | Jakk Heating And Air Conditioning | — | (805) 650 8716 | HVAC | Ventura · Ventura County | — | — |
| James B Hargraves | James B Hargraves | — | (805) 551 0508 | GC, remodel, ADU | Simi Valley · Ventura County | — | — |
| James Beaudoin Construction | James Wilbert Beaudoin | — | (805) 405 1169 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| James Clifton General Contractor | James Clifton General Contractor | — | (805) 947 7326 | GC, remodel, ADU | Camarillo · Ventura County | — | — |
| James Co Plumbing | Justin Lee James | — | (818) 486 7484 | Other | Simi Valley · Ventura County | — | — |
| James D. Lawrence Inc. DBA Lawrence Coatings - Wallcovering | James David Lawrence | — | (805) 312 6112 | GC, remodel, ADU | Camarillo · Ventura County | — | — |
| James Edward Marsh Jr | James Edward Marsh Jr | — | (805) 642 0121 | Electricians | Ventura · Ventura County | — | — |
| James Flooring | James Flooring | — | (805) 509 4300 | Other | Port Hueneme · Ventura County | — | — |
| James J Coniglio | James J Coniglio | — | (805) 258 2556 | Other | Ventura · Ventura County | — | — |
| James K Brown Jr | James K Brown Jr | — | (805) 653 0543 | Windows, patio, painters | Ventura · Ventura County | — | — |
| James Manion | James Manion | — | (805) 285 8331 | HVAC | Simi Valley · Ventura County | — | — |
| James Masters Construction | James Spears Masters | — | (805) 796 9608 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| James Mingura Tile & Stone | James Mingura Tile & Stone | — | (805) 300 2574 | Other | Thousand Oaks · Ventura County | — | — |
| James Plumbing Company | Jeremy Michael James | — | (805) 583 5744 | Other | Simi Valley · Ventura County | — | — |
| James R English | James R English | — | (805) 504 6651 | GC, remodel, ADU | Camarillo · Ventura County | — | — |
| James Taylor DBA Enhanced Finish Drywall | Enhanced Finish Drywall | — | (805) 701 1290 | Other | Ojai · Ventura County | — | — |
| James Todd Priest | James Todd Priest | — | (805) 490 9421 | Electricians | Newbury Park · Ventura County | — | — |
| James V Wyman Painting | James V Wyman Painting | — | (805) 658 6781 | Windows, patio, painters | Ventura · Ventura County | — | — |
| James W Harasta Jr | James W Harasta Jr | — | (805) 320 5759 | GC, remodel, ADU | Ventura · Ventura County | — | — |
| James Wayne Electric INC | James Mark Wayne | — | (805) 987 1028 | Electricians | Camarillo · Ventura County | — | — |
| James Worden | James Worden | — | (805) 657 6798 | GC, remodel, ADU | Ventura · Ventura County | — | — |
| James' Electricare | James' Electricare | — | (805) 312 6155 | Electricians | Thousand Oaks · Ventura County | — | — |
| Jamison Construction Corp | Britton Jamison Reed | contact@jamison-construction.com | (530) 306 6874 | GC, remodel, ADU | Ventura · Ventura County | — | — |
| Jan C Scow | Jan C Scow | — | (805) 272 8095 | Windows, patio, painters | Ojai · Ventura County | — | — |