| Joel's Plumbing INC | Joel Hernandez Magana | — | (805) 499 7286 | Other | Newbury Park · Ventura County | — | — |
| Joel’s Roofing And Rain Gutter | Joel’s Roofing And Rain Gutter | — | (805) 679-9588 | Other roofers | Ventura · Ventura County | — | — |
| John Allan Skultin | John Allan Skultin | — | (805) 404 4387 | Other | Camarillo · Ventura County | — | — |
| John Blandin Masonry | John Blandin Masonry | — | (818) 822 4656 | Other | Moorpark · Ventura County | — | — |
| John Brazauskas Gardening | John Brazauskas Gardening | — | (805) 376 2247 | Windows, patio, painters | Newbury Park · Ventura County | — | — |
| John C Mellon | John C Mellon | — | (805) 722 5776 | GC, remodel, ADU | Oxnard · Ventura County | — | — |
| John Coyne | John Coyne | — | (805) 304 7150 | Other | Simi Valley · Ventura County | — | — |
| John Davis Jr Construction INC | John Howard Jr Davis | — | (805) 496 7081 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| John Donaldson Construction INC | John William Donaldson | — | (805) 645 1359 | GC, remodel, ADU | Ventura · Ventura County | — | — |
| John F Ahearn | John F Ahearn | — | (818) 631 6747 | GC, remodel, ADU | Westlake Village · Ventura County | — | — |
| John F Culbertson | John F Culbertson | — | (805) 642 2404 | Electricians | Ventura · Ventura County | — | — |
| John H Roddenberry | John H Roddenberry | — | (805) 895 1137 | Windows, patio, painters | Newbury Park · Ventura County | — | — |
| John Ingersoll | John Ingersoll | — | (805) 587 3558 | GC, remodel, ADU | Simi Valley · Ventura County | — | — |
| John L Boryszewski Electric | John Louis Boryszewski | — | (714) 650 4842 | Electricians | Simi Valley · Ventura County | — | — |
| John M Gregorchuk General Building Contractor | John Michael Gregorchuk | — | (818) 856 0146 | GC, remodel, ADU | Moorpark · Ventura County | — | — |
| John M La Barbera Construction | John Michael La Barbera | — | (805) 630 9332 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| John M Puklus | John M Puklus | — | (805) 796 1642 | GC, remodel, ADU | Camarillo · Ventura County | — | — |
| John M Von Rueden | John M Von Rueden | — | (805) 389 1963 | Other | Moorpark · Ventura County | — | — |
| John M Walden Construction Company | John Mitchel Walden | — | (805) 484 4838 | GC, remodel, ADU | Simi Valley · Ventura County | — | — |
| John Mackenzie | John Mackenzie | — | (818) 970 6989 | Electricians | Simi Valley · Ventura County | — | — |
| John Michael Ryan Construction | John Michael Ryan | — | (818) 612 0465 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| John Miecke Construction | John Daniel Miecke | — | (805) 304 2004 | GC, remodel, ADU | Simi Valley · Ventura County | — | — |
| John Oliver Construction | John Frederick Oliver | — | (818) 335 7993 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| John P Candreva | John P Candreva | — | (805) 496 6754 | Electricians | Thousand Oaks · Ventura County | — | — |
| John Pence Building Specialties INC | Matthew Todd Whitecomb | — | (805) 642 8139 | GC, remodel, ADU | Oxnard · Ventura County | — | — |
| John Porsia | John Porsia | — | (818) 292 6068 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| John Retich Electric INC | John Gilbert Retich | — | (805) 876 0353 | Electricians | Moorpark · Ventura County | — | — |
| John Richardson | John Richardson | — | (818) 519 5886 | Other | Thousand Oaks · Ventura County | — | — |
| John S Hamilton Jr | John S Hamilton Jr | — | (818) 435 6200 | GC, remodel, ADU | Westlake Village · Ventura County | — | — |
| John Skiba Construction Company | John Donald Skiba | — | (805) 827 3502 | GC, remodel, ADU | Ojai · Ventura County | — | — |
| John Spradlin | John Spradlin | — | (860) 662 1271 | GC, remodel, ADU | Ojai · Ventura County | — | — |
| John Stanley Adamick | John Stanley Adamick | — | (818) 846 0724 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| John Sveiven Electric | John Andrew Sveiven | — | (805) 746 0563 | Electricians | Ventura · Ventura County | — | — |
| John T De Domenico Jr | John T De Domenico Jr | — | (805) 432 6907 | GC, remodel, ADU | Newbury Park · Ventura County | — | — |
| John Thomson Construction | John D Thomson | — | (805) 279 5200 | GC, remodel, ADU | Ojai · Ventura County | — | — |
| John Van Brocklin Baade | John Van Brocklin Baade | — | (805) 910 8627 | Other | Newbury Park · Ventura County | — | — |
| John Van Patt DBA Old World Craftsman | Old World Craftsman | — | (805) 644 3471 | Other | Ventura · Ventura County | — | — |
| John Villani DBA Preferred Painters | John Villani DBA Preferred Painters | — | (805) 630 6600 | Windows, patio, painters | Simi Valley · Ventura County | — | — |
| John Wade | John Wade | — | (818) 789 9790 | Other | Simi Valley · Ventura County | — | — |
| John White Plumbing | John White Plumbing | — | (530) 545 3787 | Other | Oxnard · Ventura County | — | — |