| Antonio's Roofing | Renteria Antonio | — | (707) 399 8274 | Other roofers | Fairfield · Solano County | — | — |
| Anvil General Contractors INC | Jesus Montes-Gaxiola | — | (510) 988 1058 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Ap Plumbing Co | Oscar Julian Pena Aguilera | — | (707) 304 1690 | Other | Vallejo · Solano County | — | — |
| Apex Acoustics INC | Daniel Morgan Marrocco | — | (707) 290 3068 | Other | Fairfield · Solano County | — | — |
| Apex Fiber LLC | Tyler Robert Hays | yaron@apexfiber.com | (707) 514 5762 | Other | Vacaville · Solano County | — | — |
| Apex Paving Construction | Zachariah Edison Stanley | — | (408) 334 4002 | Other | Vacaville · Solano County | — | — |
| Appiano's Installations INC | Vincent John Appiano | — | (707) 592 2548 | Other | Benicia · Solano County | — | — |
| Apw Interiors | Michael Charles Lee | — | (916) 716 6508 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Aqua Clear Pool Service LLC | Bradley Joseph Tyrrell | — | (707) 448 9200 | Pool | Vacaville · Solano County | — | — |
| Aquacover Pool & Spa | Vazquez Juan | — | (707) 202 4223 | Pool | Vallejo · Solano County | — | — |
| Aquatic Environments | George Peter Forni | — | (888) 480 5253 | Other | Suisun · Solano County | — | — |
| Architectural Construction | Randy Lee Greer | — | (707) 425 1903 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Archuleta Drywall & Plaster | Donald Eugene Archuleta | — | (815) 279 8186 | Other | Fairfield · Solano County | — | — |
| Argumedo Custom Painting Corporation | Juan Francisco Argumedo-Telles | — | (415) 246 3892 | Windows, patio, painters | Vallejo · Solano County | — | — |
| Aries Y Libra INC | Campos Rodolfo Zavalza | — | (707) 392 6487 | Windows, patio, painters | Suisun · Solano County | — | — |
| Armas Engineering INC | Deborah Beans Armour | — | (833) 432 1222 | Electricians | Vacaville · Solano County | — | — |
| Armour Petroleum Service And Equipment Corporation | Michael Anthony Armour | — | (707) 437 6668 | Electricians | Vacaville · Solano County | — | — |
| Arrow A Fence Co | Jonathan West Lee | — | (707) 561 1574 | Other | Benicia · Solano County | — | — |
| Arthur Steven Bergesen | Arthur Steven Bergesen | — | (925) 963 7408 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Artisan Hardscapes INC | Rio Daniel Del | — | (707) 400 4785 | Windows, patio, painters | Benicia · Solano County | — | — |
| Artistic Tile And Marble | Artistic Tile And Marble | luis@artistictilemarble.com | (707) 580 8795 | Other | Vacaville · Solano County | — | — |
| Artiszen Tile Stone Mosaic | Artiszen Tile Stone Mosaic | — | (707) 649 8984 | Other | Vallejo · Solano County | — | — |
| Arturo Gallegos-lopez | Arturo Gallegos-lopez | — | (707) 310 2475 | GC, remodel, ADU | Vallejo · Solano County | — | — |
| Arturo's Drywall INC | Higuera Arturo Molina | — | (707) 720 8179 | Other | Fairfield · Solano County | — | — |
| Ascariz Construction | Frank Jr Ascariz | — | (707) 249 5355 | GC, remodel, ADU | Fairfield · Solano County | — | — |
| Ascher Construction INC | Adam Andrew Ascher | — | (707) 678 1800 | GC, remodel, ADU | Dixon · Solano County | — | — |
| Ashcraft Construction | Jonathan David Ashcraft | — | (707) 479 6274 | GC, remodel, ADU | Vacaville · Solano County | — | — |
| Aspect Landscapes INC | Joel Curtin Wong | — | (530) 219 5562 | Windows, patio, painters | Fairfield · Solano County | — | — |
| Asphalt Solutions | Frank Junior Stanley | — | (707) 761 1004 | Other | Vacaville · Solano County | — | — |
| Asta Construction Co INC | Christian Edward Koenig | — | (707) 374 6472 | Other | Rio Vista · Solano County | — | — |
| Atc Specialties INC | Anthony Wilfred Cosgrove | — | (707) 980 5009 | GC, remodel, ADU | Vallejo · Solano County | — | — |
| Atkinson Land Leveling | Atkinson Land Leveling | — | (707) 447 2835 | Other | Dixon · Solano County | — | — |
| Atlantis Painting Co | Dionysios Laertis Moraitis | — | (707) 644 8277 | Windows, patio, painters | Vallejo · Solano County | — | — |
| Atlantis Painting Partnership | Nicholaos Laertis Moraitis | — | (707) 644 8277 | Windows, patio, painters | Vallejo · Solano County | — | — |
| Atlas Voice & Data LLC | Youssef Murcia | — | (415) 294 0656 | Other | Vacaville · Solano County | — | — |
| Austin's Air Conditioning And Heating INC | David Castillo Mendoza | — | (707) 422 2593 | HVAC | Vacaville · Solano County | — | — |
| Ava Steel | Ava Steel | — | (650) 270 6316 | Other | Suisun City · Solano County | — | — |
| Avalon Construction & Facility Services INC | Luis Alfredo Perez | — | (510) 488 8081 | HVAC | Vacaville · Solano County | — | — |
| Avila Drywall | Avila Drywall | — | (707) 389 5666 | Other | Dixon · Solano County | — | — |
| Award Painting Co | Karastogiannis Dimitrios | — | (707) 429 0143 | Windows, patio, painters | Fairfield · Solano County | — | — |