| Integrated Facility Services INC | Bradley Alan Proctor | interested@domainmarket.com | (510) 487 7701 | Other | Hayward · Alameda County | — | — |
| Integrated Sign Installations INC | Jan Jack Soltys | — | (510) 324 1500 | Other | Union City · Alameda County | — | — |
| Integrity Construction & Flooring | Kelly Andrew Vigil | — | (510) 556 1463 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Integrity Construction And Millwork LLC | Pat Pasquale Jr Ansuini | — | (408) 781 0006 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| Integrity First Construction INC | Ricardo Mendoza Maciel | — | (925) 766 0983 | GC, remodel, ADU | Alameda · Alameda County | — | — |
| Integrity Garage Doors And Gates INC | Dean Regev | — | (510) 566 4811 | Other | Hayward · Alameda County | — | — |
| Integrity Home Construction INC | Jorge Daniel Ocegueda | interested@domainmarket.com | (510) 586 5441 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Integrity Paint And Design | Integrity Paint And Design | — | (510) 410 9805 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Integrity Remodeling Company INC | Eli Ross Israel | info@integrityremodeling.com | (415) 302 0829 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Integrity Roofing Systems INC | Jamin Bryan Broom | — | (925) 999 0101 | Other roofers | Pleasanton · Alameda County | — | — |
| Intelligent Energy LLC | Pressnall Che | iejapan@intelligent-energy.com | (415) 377 8954 | Electricians | Oakland · Alameda County | — | — |
| Interior Management Group INC | Ronnie Alan Albarillo | — | (510) 259 1200 | Other | Hayward · Alameda County | — | — |
| Interior Systems Drywall | Interior Systems Drywall | — | (510) 715 2541 | Other | Castro Valley · Alameda County | — | — |
| International Coating Company | Hatton Mark | interested@domainmarket.com | (925) 470 8982 | Windows, patio, painters | Oakland · Alameda County | — | — |
| International Energy Resources LLC DBA Ambient Experts HVAC | Fernandez Adam | — | (510) 730 5959 | HVAC | Oakland · Alameda County | — | — |
| International Swim Center-2026 LLC | Mark Construction INC Scott | — | (925) 828 3100 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| Interstate Roofing And Solar | Josephine Ma Wong | — | (510) 639 0833 | Other roofers | Oakland · Alameda County | — | — |
| Intra Wall Covering | Intra Wall Covering | — | (510) 266 5744 | Other | Hayward · Alameda County | — | — |
| Intuitive Landscape Services | Oscar S Vega | — | (510) 798 3184 | Windows, patio, painters | Oakland · Alameda County | — | — |
| Invictus Construction | Eric James Cunningham | — | (510) 209 1245 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Ionian Builders LLC | Konstantine Theodore Paxinos | ionianbuildersllc@gmail.com | (415) 369 7779 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Ionut Construction | Chiorean Ionut | — | (510) 461 9327 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Ip Electric | Israel Alberto Perez Lopez | — | (650) 465 2216 | Electricians | Hayward · Alameda County | — | — |
| Iron Horse Heating And Cooling | Iron Horse Heating And Cooling | — | (925) 518 1907 | HVAC | Livermore · Alameda County | — | — |
| Iron Sight Construction | Ramon Alejandro Ii Avellar | — | (725) 666 3165 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Irongrain INC | Andrew Thomas Williams | info@irongrain.com | (510) 915 4308 | Other | Oakland · Alameda County | — | — |
| Isaac Rion Construction | Isaac Rion Andrade | — | (925) 519 6615 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Island Construction | Walter Lewis Decelle | — | (510) 909 4362 | GC, remodel, ADU | Alameda · Alameda County | — | — |
| Island Electric | Caleb Samuel Sanchez | — | (858) 610 3953 | Electricians | Alameda · Alameda County | — | — |
| Ismail's Shades & Blinds | Ismail's Shades & Blinds | — | (650) 785 2699 | Other | Fremont · Alameda County | — | — |
| Iso Plumbing INC | Ismet Jr Redzic | — | (510) 798 4804 | Other | San Lorenzo · Alameda County | — | — |
| Issaac Roofing | Yong Kun Choe | — | (510) 913 1812 | Other roofers | Castro Valley · Alameda County | — | — |
| Itales Rodrigues | Itales Rodrigues | — | (408) 829 8672 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Ivan Ivanov | Ivan Ivanov | ivanivanov@ipconsulting.eu | (925) 639 9367 | Other | Dublin · Alameda County | — | — |
| Ivy Painting Co | Myung Kuk Lee | — | (510) 520 7771 | Windows, patio, painters | Oakland · Alameda County | — | — |
| Iweb Construction Management Corporation | Sui-Yeung Lau | — | (510) 282 0428 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| J & A Construction | Guan Hua Yu | — | (510) 882 8089 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| J & A General Contractor | Jose Maria Duarte | — | (510) 589 6987 | GC, remodel, ADU | San Lorenzo · Alameda County | — | — |
| J & C Safety 1st Fire Protection INC | Jayden Michael Ortiz | — | (650) 621 0672 | Other | Hayward · Alameda County | — | — |
| J & D Glass & Sash INC | Matthew T Viscovich | — | (510) 843 9391 | Windows, patio, painters | Berkeley · Alameda County | — | — |