| K&l Construction And Development | Kaewett Carlyle Nelson | — | (206) 962 1090 | GC, remodel, ADU | Hoopa · Humboldt County | — | — |
| K2v Concrete INC | Michael Joseph Vandal | — | (707) 498 0699 | GC, remodel, ADU | Blue Lake · Humboldt County | — | — |
| Kapel Construction INC | Lance E Robbins | — | (530) 515 6050 | Other | Hoopa · Humboldt County | — | — |
| Karges Flooring | Karges Flooring | josh@kargesflooring.com | (530) 905 3062 | Other | Eureka · Humboldt County | — | — |
| Karl Benemann Contracting | Karl Francis Benemann | — | (707) 499 6252 | GC, remodel, ADU | Trinidad · Humboldt County | — | — |
| Katri And Dart Electric | Jerod Joseph Katri | — | (707) 599 5779 | Electricians | Eureka · Humboldt County | — | — |
| Kb Excavation LLC | Kevin Lea Pelascini | — | (707) 616 9611 | Other | Eureka · Humboldt County | — | — |
| Keefe Plumbing | Keefe Plumbing | — | (707) 223 3392 | Other | Miranda · Humboldt County | — | — |
| Keith Mann Construction | Keith Ryan Mann | — | (707) 273 0351 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Keller Construction | Jeremiah Paul Keller | resumes@kellerconstruction.com | (707) 496 4163 | GC, remodel, ADU | Rio Dell · Humboldt County | — | — |
| Kellogg Construction | Andrew William Kellogg | info@kellogg-construction.com | (707) 616 6763 | GC, remodel, ADU | Arcata · Humboldt County | — | — |
| Kenneth G Fleck Plumbing | Kenneth G Fleck Plumbing | — | (707) 496 9988 | Other | Cutten · Humboldt County | — | — |
| Kernen Construction | Norman Scott Farley | office@kernenconstruction.com | (707) 826 8686 | GC, remodel, ADU | Blue Lake · Humboldt County | — | — |
| Kevin Bradshaw Outdoor Creations | Kevin Bradshaw Outdoor Creations | — | (707) 502 7809 | Windows, patio, painters | Eureka · Humboldt County | — | — |
| Kevin Brown | Kevin Brown | — | (530) 629 3702 | Other | Willow Creek · Humboldt County | — | — |
| Kevin Hulcy Electric | Kevin James Hulcy | — | (707) 599 0846 | Electricians | Eureka · Humboldt County | — | — |
| Kevin Jacquemet | Kevin Jacquemet | — | (707) 839 3960 | GC, remodel, ADU | Arcata · Humboldt County | — | — |
| Kim H Frye | Kim H Frye | — | (707) 442 6660 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| King Peak Construction | Michael Eric Ryan | — | (707) 629 3608 | GC, remodel, ADU | Petrolia · Humboldt County | — | — |
| Kingtide Design And Build | Matthew Diggins | — | (707) 601 7474 | GC, remodel, ADU | Bayside · Humboldt County | — | — |
| Kirk Sandifer Construction | Kirk L Sandifer | — | (707) 499 5487 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Kirkendall Built | Kirkendall Built | — | (707) 498 2278 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Kna Construction | Kenneth Robert Nunes | — | (707) 654 0047 | GC, remodel, ADU | Whitethorn · Humboldt County | — | — |
| Kramer Properties INC | Kurt Gaskins Kramer | — | (707) 444 2919 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| Kraus Builds | Kraus Builds | — | (707) 834 8797 | GC, remodel, ADU | Arcata · Humboldt County | — | — |
| Kris Wells Construction | Kristopher Allen Wells | — | (707) 499 6687 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Kriterion Construction Services INC | Kenneth Ray Keating | — | (707) 267 8565 | GC, remodel, ADU | Fortuna · Humboldt County | — | — |
| Krs Electric | Kevin Michael Roberts | — | (707) 601 8533 | Electricians | Blue Lake · Humboldt County | — | — |
| Kurt E Gast General Engineering Contractor | Kurt Erich Gast | — | (707) 496 2853 | Other | Eureka · Humboldt County | — | — |
| Kurt Papstein Construction | Kurt Adams Papstein | — | (707) 407 9308 | GC, remodel, ADU | Eureka · Humboldt County | — | — |
| L D H Construction Services | Larry Dean Haug | — | (707) 839 9424 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| L J Stolz Construction | Leonard Jay Stolz | — | (530) 228 3130 | GC, remodel, ADU | Carlotta · Humboldt County | — | — |
| Landscapes By Lisette | Landscapes By Lisette | — | (707) 834 0606 | Windows, patio, painters | Mc Kinleyville · Humboldt County | — | — |
| Langdon Construction | Gavyn David Langdon | info@langdonconstruction.com | (707) 496 7533 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Langdon Painting | Langdon Painting | — | (707) 445 5968 | Windows, patio, painters | Eureka · Humboldt County | — | — |
| Larson Custom Woodworks | Larson Custom Woodworks | larsoncustomwoodworks@gmail.com | (707) 834 9242 | Other | Arcata · Humboldt County | — | — |
| Laura E Lopez | Laura E Lopez | — | (805) 464 8307 | Windows, patio, painters | Arcata · Humboldt County | — | — |
| Lawrence Construction | Brian David Lawrence | info@lawrence-construction.com | (707) 498 9618 | GC, remodel, ADU | Mc Kinleyville · Humboldt County | — | — |
| Layne Martin Construction | Layne Daniel Martin | — | (707) 362 4489 | GC, remodel, ADU | Fieldbrook · Humboldt County | — | — |
| Left Coast Painting | Left Coast Painting | — | (707) 499 4276 | Windows, patio, painters | Eureka · Humboldt County | — | — |