| Redwood Community Action Agency | Marlene E Jurkovich | — | (707) 269 2001 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Redwood Community Action Agency | Matthew Michael Drummond | — | (707) 269 2001 | Windows, patio, painters | Eureka · Humboldt County | — | — |
| Redwood Construction | Jonathan Fredrick Copeland | — | (707) 599 2948 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Redwood Curtain Construction | Jeremy David Burns | — | (707) 496 5171 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Redwood Empire Roofing INC | Robert James Sirrine | info@redwoodempireroofing.com | (707) 725 7663 | Other roofers | Fortuna · Humboldt County | — | — |
| Redwood Energy | Redwood Energy | admin@redwoodenergy.net | (707) 234-7573 | EV chargers | Arcata · Humboldt County | — | — |
| Redwood Glass & Window | Redwood Glass & Window | redwoodglass@gmail.com | (541) 476-8101 | Windows, patio, painters | Eureka · Humboldt County | — | — |
| Redwood Mechanical | Redwood Mechanical | — | (707) 273 5066 | HVAC | Eureka · Humboldt County | — | — |
| Redwood Remodeling | Aaron Paul Gustaveson | — | (707) 845 8468 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Redwood Roots Construction | Jason Lee Stephens | — | (707) 599 9141 | GC, remodel, ADU | Willow Creek · Humboldt County | — | — |
| Regalo Electric | Paul Simoes Regalo | — | (707) 267 8810 | Electricians | Eureka · Humboldt County | — | — |
| Reid Construction | Arlin Robert Reid | info@reidconstruction.com | (707) 499 3077 | GC, remodel, ADU | Shelter Cove · Humboldt County | — | — |
| Reliabuild Contracting | Travis Alden Tirsbeck | — | (707) 740 5772 | GC, remodel, ADU | Fortuna · Humboldt County | — | — |
| Renner Russ Construction | Russell Steven Renner | — | (707) 822 9511 | Other | Fortuna · Humboldt County | — | — |
| Rentor | Rentor | support@rentor.com | (707) 444-3835 | Property managers | Eureka · Humboldt County | — | — |
| Revival Home Builders INC | Shawn Edward Ellsworth | office@revivalhomebuilders.com | (707) 839 8378 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Rex Barnhart Construction Company | Rex Eugene Barnhart | — | (707) 601 0562 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Rfi Tree Services | Timothy Alan Metz | — | (707) 496 0322 | Tree | Arcata · Humboldt County | — | — |
| Rich Well & Pump Service | Stuart Wayne Dickey | — | (707) 839 1087 | Other | Mc Kinleyville · Humboldt County | — | — |
| Rich Well Drilling & Pump Service INC | Stuart Wayne Dickey | — | (707) 839 1087 | Other | Mc Kinleyville · Humboldt County | — | — |
| Richard Friesen | Richard Friesen | — | (707) 499 4402 | GC, remodel, ADU | Hydesville · Humboldt County | — | — |
| Richard Winans Construction | Richard Alan Winans | — | (707) 616 7231 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Richter Construction | Bryan Keith Richter | — | (707) 496 6445 | GC, remodel, ADU | Hydesville · Humboldt County | — | — |
| Rick Willits Wood Floors | Rick Willits Wood Floors | — | (707) 834 7754 | Other | Blue Lake · Humboldt County | — | — |
| Right Way Painting | Right Way Painting | — | (707) 498 4692 | Windows, patio, painters | Eureka · Humboldt County | — | — |
| Rise Energy | Paul Newkirk Woodworth | — | (707) 502 7229 | Electricians | Arcata · Humboldt County | — | — |
| Robert Bruce Johnson | Robert Bruce Johnson | — | (707) 834 7800 | Pool | Mc Kinleyville · Humboldt County | — | — |
| Robert Colburn Electric INC DBA Colburn Electric | Robert Barkley Colburn | office@colburn-electric.com | (707) 445 8474 | Electricians | Eureka · Humboldt County | — | — |
| Robert Goodman | Robert Goodman | — | (707) 496 1140 | Electricians | Arcata · Humboldt County | — | — |
| Robert Moulton Construction | Robert Lynn Moulton | — | (707) 483 8069 | GC, remodel, ADU | Loleta · Humboldt County | — | — |
| Robert P Blankenship Corporation DBA Blankenship Gates | Robert Paul Blankenship | — | (707) 223 0137 | GC, remodel, ADU | Ferndale · Humboldt County | — | — |
| Roberts D W L | Roberts D W L | — | (707) 496 0812 | Other | Bridgeville · Humboldt County | — | — |
| Robertson Construction | Phillip Edward Robertson | dave@robertsonconstruction.com | (321) 795-3655 | GC, remodel, ADU | Arcata · Humboldt County | — | — |
| Robinson Homes | Robinson Homes | accessibility@incomrealestate.com | (707) 834 6775 | GC, remodel, ADU | Fortuna · Humboldt County | — | — |
| Robinson Trucking And Equipment LLC | Ryan Carl Robinson | — | (707) 834 2095 | Other | Blue Lake · Humboldt County | — | — |
| Rock Solid Construction | Matthew Leif Olson | interested@domainmarket.com | (707) 496 7625 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Rodan Construction | Daniel Jay Oram | — | (707) 496 6611 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Roe Construction | Eric William Roe | — | (707) 630 1397 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Roger | Roger | — | (707) 444 9901 | Electricians | Arcata · Humboldt County | — | — |
| Roger Dale Brown Jr | Roger Dale Brown Jr | — | (530) 629 3702 | Other | Willow Creek · Humboldt County | — | — |