| Hood Consulting Services | David Allen Hood | — | (949) 633 6244 | GC, remodel, ADU | Dixon · Solano County | — | — |
| Horizon Construction | Barry Glenn Nash | — | (707) 446 6168 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Horizon Millwork INC | Barry Glenn Nash | — | (707) 446 6185 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Howard Drywall | Howard Drywall | — | (707) 330 0879 | Other | Vacaville · Solano County | — | — |
| Hrm Landscape | Hrm Landscape | — | (530) 558 9032 | GC, remodel, ADU | Benicia · Solano County | — | — |
| Hs Drywall | Hs Drywall | — | (925) 285 4606 | Other | Vallejo · Solano County | — | — |
| Ht Landscaping | Jason Tran | — | (510) 935 2532 | Windows, patio, painters | Vallejo · Solano County | — | — |
| Htb Concrete INC | Tinoco Bermudez Hugo | — | (707) 365 5978 | Other | Vacaville · Solano County | — | — |
| Hughes & Co Renovations | Conner Jordan Tyler Hughes | — | (707) 492 6322 | GC, remodel, ADU | Benicia · Solano County | — | — |
| Hugo Hernandez | Hugo Hernandez | — | (510) 472 1379 | Other | Fairfield · Solano County | — | — |
| Hv Colonial Flooring INC | Mendez Carlos Hinojosa | — | (707) 514 6799 | Other | Vacaville · Solano County | — | — |
| Hv Painting INC | Hugo Jacobo Vargas | — | (707) 208 0745 | Windows, patio, painters | Fairfield · Solano County | — | — |
| HVAC Heros | Brian Tyler Avila | — | (707) 514 8151 | HVAC | Vacaville · Solano County | — | — |
| Hydronics Plus - Radiant & Plumbing INC | Omar Melecio Pedraza | — | (707) 363 9829 | Other | Fairfield · Solano County | — | — |
| I C Construction | Baltazar Dilso | — | (510) 719 7203 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| I P A Construction | Darrick Jonathan Chavis | — | (925) 956 6342 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Ibarra Custom Flooring | Ibarra Custom Flooring | — | (707) 416 5112 | Other | Fairfield · Solano County | — | — |
| Iconic Construction Electric And Controls | Jeffrey Daniel Elkins | — | (909) 503 8901 | Electricians | Vallejo · Solano County | — | — |
| Impact Restoration & Construction | Bimbo Michael | impactrestorationconstruction@gmail.com | (707) 816 9937 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Imperial Brick & Stone Masonry INC | Jose Antonio Colin Moctezuma | — | (707) 704 0593 | Other | Vallejo · Solano County | — | — |
| In & Out Garage Door Repair And Installation | Hamza Ashraf Marini | — | (916) 390 8453 | Other | Fairfield · Solano County | — | — |
| Independent Contractor INC DBA Independent Engineering Contractor | Alberto Ferreira Morato Filho | — | (650) 444 5162 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Indoor Air Technologies | Andrew Jerrell Meeks | — | (707) 710 8544 | HVAC | Fairfield · Solano County | — | — |
| Industrial Railways Co | Stephen Craig Nolan | — | (707) 361 5732 | Other | Benicia · Solano County | — | — |
| Infinity Tile Co | Guillermo Carrasco | — | (707) 396 0488 | Other | Vallejo · Solano County | — | — |
| Inishowen Construction | Andrew Thomas Mc Grory | — | (415) 305 2282 | GC, remodel, ADU | Vallejo · Solano County | — | — |
| Innovative Concrete Solutions INC | Jose Ramon Gonzalez Rodriguez | — | (707) 580 5476 | Other | Fairfield · Solano County | — | — |
| Innovative Electric LLC | Richard Dean Jr Hawley | — | (707) 628 7604 | Electricians | Vacaville · Solano County | — | — |
| Innovative Radiant Heating | Nicole Marie D Ponce | — | (707) 439 3502 | HVAC | Fairfield · Solano County | — | — |
| Insight Glass | Paul Michael Greco | info@insightglass.com | (707) 746 6571 | Windows, patio, painters | Benicia · Solano County | — | — |
| Insight Renovations | Insight Renovations | — | (707) 718 5452 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Instaservice Painting INC | Claudio Alberto Tinoco | — | (415) 726 0059 | Windows, patio, painters | Vacaville · Solano County | — | — |
| Integrated Glass Concepts INC | Damian Lee Ingle | — | (707) 580 3837 | Windows, patio, painters | Benicia · Solano County | — | — |
| Integrated Surfaces Flooring INC | Lisa Michelle Murphy | — | (925) 786 7971 | Other | Benicia · Solano County | — | — |
| Integrity Data & Fiber INC | Abrahm Robert Wakerley | jmiller@integritydatafiber.com | (916) 439 2351 | Other | Vacaville · Solano County | — | — |
| Integrity Plumbing | Integrity Plumbing | — | (707) 631 5720 | Other | Fairfield · Solano County | — | — |
| Integrity.us | Raquel Geri Avitia | — | (925) 446 4442 | Other | Benicia · Solano County | — | — |
| Interior Wood Protection Services INC | Joseph Onukwufor Jr Njoku-Obi | — | (415) 971 3869 | Windows, patio, painters | Rio Vista · Solano County | — | — |
| Interiors 2 Exteriors | Interiors 2 Exteriors | — | (833) 955-5666 | Inspectors | Fairfield · Solano County | — | — |
| Internet Free Planet INC | George Marshall Abernathy | — | (707) 330 3872 | Electricians | Vacaville · Solano County | — | — |