| An Electrician INC | Douglas Clark Daly | interested@domainmarket.com | (707) 834 6596 | Electricians | Eureka · Humboldt County | — | — |
| Anderson Built Construction | Brandon Nicholas Anderson | — | (707) 496 5398 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Anderson Construction | Jeremiah Lee Anderson | — | (707) 498 1420 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Andrew Sederberg | Andrew Sederberg | — | (707) 496 3225 | GC, remodel, ADU | Loleta · Humboldt County | — | — |
| Andy Lane | Andy Lane | andy@andylane.com | (707) 839 2263 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Anthonys Tile | Anthonys Tile | anthonystile@gmail.com | (707) 362 6356 | Other | Mc Kinleyville · Humboldt County | — | — |
| Anu Way Construction | Nathaniel Andrew Schneider | — | (707) 273 3715 | GC, remodel, ADU | Hydesville · Humboldt County | — | — |
| Ap Property Management | Ap Property Management | — | (707) 726-2379 | Property managers | Fortuna · Humboldt County | — | — |
| Apex Building Solutions | Anthony Allan Thompson | admin@apex-building-solutions.com | (707) 601 0740 | GC, remodel, ADU | Bayside · Humboldt County | — | — |
| Arbco Construction | Norman Gregg Arbec | — | (707) 845 0402 | GC, remodel, ADU | Cutten · Humboldt County | — | — |
| Arcata Building Co. | Jonathan Eugene Fechner | — | (707) 407 5623 | GC, remodel, ADU | Blue Lake · Humboldt County | — | — |
| Arcata Cabinet & Design Company | Casey Eric Patton | — | (707) 826 2680 | Other | Arcata · Humboldt County | — | — |
| Arcata Finish Carpentry Fabricators | Arcata Finish Carpentry Fabricators | — | (707) 822 5447 | Other | Arcata · Humboldt County | — | — |
| Arcata Pro Floor INC | Lisa Louise Townsend-Scmitt | — | (707) 822 2838 | Other | Arcata · Humboldt County | — | — |
| Arcata Property Management | Arcata Property Management | — | (707) 599-2873 | Property managers | Arcata · Humboldt County | — | — |
| Arnoul Electric | Kevin Fredrick Arnoul | — | (707) 986 9709 | Electricians | Whitethorn · Humboldt County | — | — |
| Aronson Builders | Aronson Builders | — | (707) 496 2159 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Arts Roofing LLC | Arthur Lee Ii Mosier | — | (707) 916 7663 | Other roofers | Eureka · Humboldt County | — | — |
| Atkins - Salazar Construction | Terry Gene Atkins | — | (707) 496 3248 | GC, remodel, ADU | Arcata · Humboldt County | — | — |
| Azalea Building Company | Scott Lawrence Wallach | — | (707) 298 5934 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| B & B Hardscape INC | Penner Robert | — | (415) 302 0720 | Other | Eureka · Humboldt County | — | — |
| B & C Eco Friendly Construction INC | Todd Michael Bates | — | (707) 845 8410 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| B C Ferreira Construction | Brian Louis Ferreira | — | (707) 839 8853 | Other | Mc Kinleyville · Humboldt County | — | — |
| B E J Construction | Brandon Earl Johnson | — | (707) 498 1182 | GC, remodel, ADU | Kneeland · Humboldt County | — | — |
| B K Plumbing | B K Plumbing | — | (707) 616 4779 | Other | Fortuna · Humboldt County | — | — |
| B K R Electric Co | Brian Kelly Riordan | — | (707) 616 7647 | Electricians | Eureka · Humboldt County | — | — |
| B R S Fence & Landscape | Branden R Schlaht | — | (775) 722 3803 | Windows, patio, painters | Mc Kinleyville · Humboldt County | — | — |
| Backman Building Services LLC | John Michael Backman | — | (707) 499 1809 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Bailey Electric | Darrell Everrett Jr Bailey | — | (707) 445 9719 | Electricians | Eureka · Humboldt County | — | — |
| Baron Electric INC | Joel Alex Baron | joel@baron-electric.com | (707) 362-2765 | Electricians | Kneeland · Humboldt County | — | — |
| Barrer Construction | Michael Zinehart Barrer | — | (707) 599 8245 | GC, remodel, ADU | Ferndale · Humboldt County | — | — |
| Barry Smith Construction INC | Barry Conrad Smith | info@barrysmithconstruction.com | (707) 499 4386 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Bayline Construction And Remodel | Jeromy Paul Shull | — | (530) 356 2136 | GC, remodel, ADU | Blue Lake · Humboldt County | — | — |
| Bc Drain Care Plumbing | Bc Drain Care Plumbing | — | (707) 601 6867 | Other | Ferndale · Humboldt County | — | — |
| Beacom Construction Co | Earl James Jr Ambrosini | zzzzzzzzzzzzz@gmail.com | (707) 725 3323 | GC, remodel, ADU | Fortuna · Humboldt County | — | — |
| Beck Roofing | Matthew Gerald Beck | — | (707) 768 3075 | Other roofers | Hydesville · Humboldt County | — | — |
| Belak Construction Co | Peter Charles Belak | — | (707) 496 0684 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Bell's Heating | Bell's Heating | — | (707) 442 7616 | HVAC | Eureka · Humboldt County | — | — |
| Ben Construction | Hakim Nathaniel Ben-Iesau | — | (707) 840 0410 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Ben Maulden Construction INC | Ben Maulden | — | (707) 502 5718 | GC, remodel, ADU | Arcata · Humboldt County | — | — |