| Anderson Logging INC | Myles Benjamin Anderson | — | (707) 964 2770 | Other | Fort Bragg · Mendocino County | — | — |
| Anderson Valley Water Systems | Charles William Paget-Seekins | — | (707) 367 3874 | Other | Philo · Mendocino County | — | — |
| Andrew Sheet Metal | Andrew Sheet Metal | — | (707) 328 9354 | HVAC | Hopland · Mendocino County | — | — |
| Angley Electric | Allouis P Steven Angley | — | (707) 813 7778 | Electricians | Fort Bragg · Mendocino County | — | — |
| Animal Construction INC | Prometheus Gene Glover | team@latofonts.com | (707) 354 2055 | GC, remodel, ADU | Point Arena · Mendocino County | — | — |
| Apex Metal Gutters | Apex Metal Gutters | apexmetalgutters@gmail.com | (530) 665 3818 | Other | Ukiah · Mendocino County | — | — |
| Aquapoolco Pool & Spas | Aquapoolco Pool & Spas | — | (707) 463 3999 | Pool | Ukiah · Mendocino County | — | — |
| Aragon Electric | Alexander Endres Aragon | — | (707) 272 4274 | Electricians | Willits · Mendocino County | — | — |
| Arcbishop Construction INC | Brian Michael Bishop | — | (707) 391 2731 | GC, remodel, ADU | Ukiah · Mendocino County | — | — |
| Architectural Metal INC | David Allan Roderick | archmetalinc@gmail.com | (707) 744 1721 | Other roofers | Hopland · Mendocino County | — | — |
| Arntz And Son | James Richard Arntz | — | (707) 217 5449 | GC, remodel, ADU | Ukiah · Mendocino County | — | — |
| Arrow Fencing | Jay Christopher Woida | charlie@arrowfencing.com | (707) 485 1128 | Other | Calpella · Mendocino County | — | — |
| Artcraft Construction | Walter Anthony Von Fricken | — | (415) 260 2424 | GC, remodel, ADU | Willits · Mendocino County | — | — |
| Artgoddess | Artgoddess | — | (707) 684-9948 | Windows, patio, painters | Point Arena · Mendocino County | — | — |
| Artists Co-Op Of Mendocino Gallery | Artists Co-Op Of Mendocino Gallery | — | (707) 937-2217 | Windows, patio, painters | Mendocino · Mendocino County | — | — |
| Arts Council-Mendocino County | Arts Council-Mendocino County | — | (707) 463-2727 | Windows, patio, painters | Ukiah · Mendocino County | — | — |
| Artstruct | Yorgen Quent Kvinsland | — | (707) 937 6242 | GC, remodel, ADU | Mendocino · Mendocino County | — | — |
| Atkinson Welding | Atkinson Welding | — | (707) 841 6287 | Other | Willits · Mendocino County | — | — |
| Atlantis Heating & Cooling | Atlantis Heating & Cooling | — | (707) 671 2760 | HVAC | Albion · Mendocino County | — | — |
| Aum Construction INC | Ishvi Benzvi Aum | info@aumconstruction.com | (925) 322 3760 | GC, remodel, ADU | Mendocino · Mendocino County | — | — |
| B & B Equipment | B & B Equipment | — | (707) 462 8347 | Other | Ukiah · Mendocino County | — | — |
| B & B Excavation & Drilling | Beau Gregory Brown | bandbexcavate@gmail.com | (707) 485 7545 | GC, remodel, ADU | Redwood Valley · Mendocino County | — | — |
| B A S Roofing | Brian Allen Schlerf | — | (707) 462 4514 | Other roofers | Ukiah · Mendocino County | — | — |
| B B & B Builders INC | Robert Nicholas Buckle | — | (415) 602 2133 | GC, remodel, ADU | Mendocino · Mendocino County | — | — |
| B I Gonzalez Construction INC | Benjamin Israel Gonzalez | — | (707) 357 2500 | GC, remodel, ADU | Fort Bragg · Mendocino County | — | — |
| B R M Electric | Brian Robert Mc Clure | — | (707) 684 0218 | Electricians | Manchester · Mendocino County | — | — |
| B T K Builders | B T K Builders | — | (707) 696 9637 | GC, remodel, ADU | Redwood Valley · Mendocino County | — | — |
| B's Electric | Beatrice Marie Lincoln | — | (707) 489 4052 | Electricians | Covelo · Mendocino County | — | — |
| Baarsch Construction | Brian Richard Baarsch | — | (707) 462 7892 | GC, remodel, ADU | Ukiah · Mendocino County | — | — |
| Baguley Builders | Baguley Builders | — | (707) 322 3519 | GC, remodel, ADU | Hopland · Mendocino County | — | — |
| Barvitz Home Comfort | Barvitz Home Comfort | — | (707) 357 0102 | HVAC | Fort Bragg · Mendocino County | — | — |
| Baughn And Cameron | Rodney Donald Usher | — | (707) 462 5000 | GC, remodel, ADU | Ukiah · Mendocino County | — | — |
| Bazzani Construction Solutions Co | Scott Paul Bazzani | — | (707) 272 7346 | GC, remodel, ADU | Ukiah · Mendocino County | — | — |
| Bed Rock Concrete Pumping | Bed Rock Concrete Pumping | — | (707) 882 2637 | Other | Point Arena · Mendocino County | — | — |
| Beebe Built Construction INC | Christopher James Beebe | — | (707) 354 4805 | GC, remodel, ADU | Willits · Mendocino County | — | — |
| Ben Fairall | Ben Fairall | — | (707) 671 3379 | Other | Redwood Valley · Mendocino County | — | — |
| Ben Fienburgh Excavating | Fienburgh Benjamin | — | (707) 357 4992 | Other | Fort Bragg · Mendocino County | — | — |
| Berglund Electric | Randy E Berglund | — | (707) 468 5795 | Electricians | Ukiah · Mendocino County | — | — |
| Best Roofing | Isaac De Jesus Moreno Ruiz | — | (707) 734 0874 | Other roofers | Fort Bragg · Mendocino County | — | — |
| Better Built By Butler | Better Built By Butler | — | (707) 291 1410 | Electricians | Ukiah · Mendocino County | — | — |