| J R Construction | Jesse Jimenez | — | (510) 519 4970 | GC, remodel, ADU | Newark · Alameda County | — | — |
| J R Heating And Cooling Systems | Andrew Ralph Valderrama | — | (510) 889 8368 | HVAC | Hayward · Alameda County | — | — |
| J R J Construction | Jose Luis Reynoso | — | (510) 320 9325 | GC, remodel, ADU | Newark · Alameda County | — | — |
| J R Mueller Construction | Jon Robert Mueller | — | (925) 699 4828 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| J R P United Mechanical Refrigeration & Appliances INC | Jose Ruben Padilla Delgado | — | (925) 557 9869 | HVAC | Livermore · Alameda County | — | — |
| J R Pierce Plumbing Company | David Edward Barich | info@ndiscovered.com | (510) 483 5473 | HVAC | San Leandro · Alameda County | — | — |
| J R S Electric | John Robert Small | info@jrselectric.net | (510) 697 0634 | Electricians | Castro Valley · Alameda County | — | — |
| J R V Construction | Juan Ramon Vasquez | — | (510) 585 8995 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| J S Concrete Co | Sanchez Jeremias | — | (510) 909 3362 | Other | Hayward · Alameda County | — | — |
| J S Construction | Li Shaoshan | — | (415) 615 2288 | GC, remodel, ADU | San Lorenzo · Alameda County | — | — |
| J Scerbo Services | Joseph Frank Jr Scerbo | — | (925) 580 6156 | Electricians | Livermore · Alameda County | — | — |
| J T S Tree Expert INC | Veronica Bejines | — | (844) 822 8677 | Tree | Fremont · Alameda County | — | — |
| J Toscano Incorporated DBA Paul's Plumbing | Toscano Jesus | — | (510) 652 4947 | Other | Oakland · Alameda County | — | — |
| J U V INC | Vladimir Chernyavskiy | — | (510) 836 1300 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| J Ubhi Construction | Jarnail Singh Ubhi | — | (415) 992 2699 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| J V C Construction | Van Victor | — | (510) 363 9559 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| J V G Electric | Vazquez Garcia Josue | — | (510) 987 6757 | Electricians | Oakland · Alameda County | — | — |
| J V Gardening & Landscaping INC | Lopez Juan Gonzalez | — | (510) 563 9709 | Windows, patio, painters | Hayward · Alameda County | — | — |
| J W Construction | John Wallace Wilton | — | (510) 917 4650 | GC, remodel, ADU | Alameda · Alameda County | — | — |
| J W Construction | Joe Nathan Williams | — | (510) 715 5840 | Electricians | Oakland · Alameda County | — | — |
| J W Peterson Painting INC | John Wesley Peterson | customerservice@jwpetersonpainting.com | (925) 455 5864 | Windows, patio, painters | Livermore · Alameda County | — | — |
| J Z Construction | Juan Miguel Elvira | — | (510) 846 9384 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| J Z P Tree Service | Jorge Alberto Zavala Pineda | — | (510) 459 6359 | Tree | Oakland · Alameda County | — | — |
| J&b Homes LLC | Jeremy Robert Neal | — | (808) 381 4703 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| J&g Development And Restoration | Carlos Raul Pimentel Gonzalez | — | (510) 918 0851 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| J&m Builder INC | Nicholas Melamed Johnson | — | (510) 326 8792 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| J&m Heating & Cooling LLC | James Arthur Loring | info@jmheatingcooling.com | (510) 556 9811 | HVAC | Fremont · Alameda County | — | — |
| J&n Construction Co LLC | Naveed Dastagir | — | (510) 246 6222 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| J&v Pro Construction And Remodeling | Gustavo Abisay Molina Ruiz | — | (510) 461 5484 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| J's Landscaping | J's Landscaping | — | (510) 798 9408 | Windows, patio, painters | Alameda · Alameda County | — | — |
| J2 Building Services | Juan Jesus Mendoza | — | (510) 701 0159 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| J3 Qualtiy Logistic LLC | David Fernando Camacho Lopez | — | (561) 305 3440 | Other | Fremont · Alameda County | — | — |
| J3c Construction | Charles Fredrick Clewis | — | (510) 435 2781 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Jack D Olson Design & Construction Co | Jack Dennis Olson | — | (510) 377 1297 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Jack Mcilvain | Jack Mcilvain | — | (510) 521 0126 | GC, remodel, ADU | Alameda · Alameda County | — | — |
| Jacob Mr And Corporation | Isabel D Hernandez Portillo | — | (510) 499 3209 | Other | Oakland · Alameda County | — | — |
| Jae Lee | Jae Lee | — | (510) 209 9174 | Electricians | Castro Valley · Alameda County | — | — |
| Jae Pro Plumbing And Rooter | Jae Pro Plumbing And Rooter | — | (510) 737 8261 | Other | Fremont · Alameda County | — | — |
| Jae Sun Wheeler | Jae Sun Wheeler | — | (510) 558 1000 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Jaewook Jung | Jaewook Jung | — | (510) 999 2090 | Windows, patio, painters | Fremont · Alameda County | — | — |