| Kevin Anthony Blakenship | Kevin Anthony Blakenship | — | (661) 993 0335 | Electricians | Weed · Siskiyou County | — | — |
| Key Property Inspections | Key Property Inspections | — | (530) 842-4663 | Inspectors | Yreka · Siskiyou County | — | — |
| Kinkade Construction | Paul Joseph Kinkade | — | (530) 859 0939 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Kirk M Jones Construction INC | Kirk Marlow Jones | — | (530) 926 3800 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Klamath Siskiyou Art Center | Klamath Siskiyou Art Center | — | (530) 493-5668 | Windows, patio, painters | Happy Camp · Siskiyou County | — | — |
| Krueger Construction | William Collin Krueger | — | (530) 340 2800 | GC, remodel, ADU | Etna · Siskiyou County | — | — |
| Kyle Rizzardo Landscaping & Tree Trimming | Kyle Walker Rizzardo | — | (530) 598 8726 | Windows, patio, painters | Yreka · Siskiyou County | — | — |
| Landscape Upkeep Company | Raymone Edward Russell | — | (530) 340 0675 | Windows, patio, painters | Grenada · Siskiyou County | — | — |
| Larry Stock General Contractor | Larry Stock General Contractor | — | (530) 859 1550 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Lassen Construction LLC | Theodore Ellis Iii Dellaganna | — | (530) 392 7565 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Lauer Electric LLC | Michael Peter Lauer | — | (541) 220 8782 | Electricians | Mount Shasta · Siskiyou County | — | — |
| Lawrence A Kinkey Floor Covering | Lawrence A Kinkey Floor Covering | — | (530) 598 2960 | Other | Yreka · Siskiyou County | — | — |
| Layton Tree Removal INC | Trapper Wayne Layton | — | (530) 598 8345 | Tree | Yreka · Siskiyou County | — | — |
| Liberty Lumberjack LLC | Brandon Ross Schroeder | — | (530) 598 0916 | Tree | Montague · Siskiyou County | — | — |
| Lighthouse Painting Contractors Inc. | Lighthouse Painting Contractors Inc. | — | (541) 591-5698 | Windows, patio, painters | Mission Hills · Siskiyou County | — | — |
| Liss Electrical Solutions | James Donald Liss | — | (815) 690 1023 | Electricians | Mc Cloud · Siskiyou County | — | — |
| Lotus Construction | Rudolph Allen Russell | — | (530) 340 1421 | GC, remodel, ADU | Montague · Siskiyou County | — | — |
| Lovelace's Plumbing | Donald Gordon Lovelace | — | (530) 842 3023 | Other | Yreka · Siskiyou County | — | — |
| M Peters INC | Mike Troy Peters | — | (530) 842 0883 | Other | Yreka · Siskiyou County | — | — |
| Madrone Landscaping LLC | Stephen Christopher Gast | stephen@madronelandscaping.com | (530) 205 3114 | Windows, patio, painters | Yreka · Siskiyou County | — | — |
| Malby Masonry | Malby Masonry | — | (541) 414 7832 | Other | Mc Cloud · Siskiyou County | — | — |
| Marble Mountain Electric | Nicholas Karl Hansen | impallari@gmail.com | (208) 721 2690 | Electricians | Callahan · Siskiyou County | — | — |
| Mark Dias Construction | Mark Edward Dias | — | (559) 623 5535 | GC, remodel, ADU | Mount Shasta · Siskiyou County | — | — |
| Mark Johnson | Mark Johnson | help@smugmug.com | (530) 467 3107 | Other | Etna · Siskiyou County | — | — |
| Martin's General Construction | Brian Jerome Martin | — | (408) 656 7889 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Martin's Remodeling Service Incorporated | Martin Lawrence Gavaldon | — | (530) 925 9742 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Mathew J Hinz | Mathew J Hinz | — | (530) 905 0172 | Other | Yreka · Siskiyou County | — | — |
| Mayfield Construction | Patrick Michael Mayfield | — | (707) 346 0171 | GC, remodel, ADU | Happy Camp · Siskiyou County | — | — |
| Mccloud Plumbing | Mccloud Plumbing | — | (530) 859 1538 | Other | Mount Shasta · Siskiyou County | — | — |
| Mcintire Construction | Mike Aaron Mcintire | — | (530) 905 1355 | GC, remodel, ADU | Yreka · Siskiyou County | — | — |
| Mcintyre Heating And Air | Mcintyre Heating And Air | — | (530) 339 2162 | HVAC | Weed · Siskiyou County | — | — |
| Mclane Landscaping Maintenance | Mclane Landscaping Maintenance | — | (530) 923 1282 | Windows, patio, painters | Mount Shasta · Siskiyou County | — | — |
| Mcquoid Well Drilling INC | Mathew Donald Mc Quoid | — | (530) 468 5378 | Other | Fort Jones · Siskiyou County | — | — |
| Melo Excavation | Melo Excavation | — | (530) 408 8979 | Other | Mount Shasta · Siskiyou County | — | — |
| Mendenhall Plumbing | Mendenhall Plumbing | — | (530) 467 3079 | Other | Etna · Siskiyou County | — | — |
| Menzies Native Nursery | Menzies Native Nursery | — | (530) 938 4858 | Windows, patio, painters | Weed · Siskiyou County | — | — |
| Mercier Electric | John Christopher Mercier | — | (530) 340 1692 | Electricians | Yreka · Siskiyou County | — | — |
| Meta Morphic Plastering | Meta Morphic Plastering | — | (707) 396 2958 | Other | Yreka · Siskiyou County | — | — |
| Meyer & Sons Heating Plumbing & A/c INC | Louis Adam Meyer | — | (530) 235 2400 | HVAC | Dunsmuir · Siskiyou County | — | — |
| Meyer Construction | Steve Gale Meyer | — | (530) 598 5969 | GC, remodel, ADU | Greenview · Siskiyou County | — | — |