| Michael Hanson Construction | Michael Joseph Hanson | — | (530) 408 8244 | GC, remodel, ADU | Mc Cloud · Siskiyou County | — | — |
| Michael Keir Construction | Michael John Keir | — | (530) 859 2727 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Michael Raymond Otvos | Michael Raymond Otvos | — | (831) 818 1109 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Michael Seyms | Michael Seyms | — | (530) 925 6082 | GC, remodel, ADU | Mc Cloud · Siskiyou County | — | — |
| Michael Smith Electric | Michael Phillip Smith | — | (530) 925 5266 | Electricians | Weed · Siskiyou County | — | — |
| Michelle Hill Rentals | Michelle Hill Rentals | — | (530) 842-0720 | Property managers | Yreka · Siskiyou County | — | — |
| Mid Valley Electric | Joe Ray Sisk | — | (530) 905 0838 | Electricians | Montague · Siskiyou County | — | — |
| Mike Lux Construction | Mike Evan Lux | — | (530) 926 3793 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Mike Paula Floors | Mike Paula Floors | — | (530) 598 9042 | Other | Grenada · Siskiyou County | — | — |
| Minton Hometown Properties INC | Minton Hometown Properties INC | info@siskiyoucountyproperties.com | (530) 842-1996 | Property managers | Yreka · Siskiyou County | — | — |
| Morris Construction | Kyle Andrew Morris | — | (530) 643 0860 | GC, remodel, ADU | Yreka · Siskiyou County | — | — |
| Morton Builders | Morton Builders | — | (669) 305 9434 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Morton's Electrical Services LLC | Dancing Bear Morton | — | (530) 340 0799 | Electricians | Weed · Siskiyou County | — | — |
| Mount Shasta Concrete | Mount Shasta Concrete | — | (925) 817 8698 | Other | Mount Shasta · Siskiyou County | — | — |
| Mount Shasta Construction | Brandon Leroy Burns | brandon@mountshastaconstruction.com | (530) 261 1011 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Mount Shasta Pumps | Mount Shasta Pumps | — | (530) 408 8438 | Other | Mount Shasta · Siskiyou County | — | — |
| Mountain Air Heating Cooling & Refrigeration INC | Sarah Fay Mead | — | (530) 842 3910 | HVAC | Yreka · Siskiyou County | — | — |
| Mountain Builder Construction | Keven Daniel Krueger | — | (530) 768 7942 | GC, remodel, ADU | Etna · Siskiyou County | — | — |
| Mountain Engineering INC | Ross Patrick James | info@mountainengineering.com | (530) 356 4946 | Other | Fort Jones · Siskiyou County | — | — |
| Msc Landscape | Nathan Scott Gilliam | info@msclandscape.com | (530) 859 1208 | Windows, patio, painters | Mt Shasta · Siskiyou County | — | — |
| Mt Shasta Garage Doors | Mt Shasta Garage Doors | info@indiantypefoundry.com | (530) 859 1488 | Other | Mt Shasta · Siskiyou County | — | — |
| N B I Industries | N B I Industries | — | (714) 277 8969 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Native Grounds Nursery & Landscape INC | Kristen Whitney Sellmer | — | (530) 926 0555 | Windows, patio, painters | Mt Shasta · Siskiyou County | — | — |
| Naylor Construction | Gerald Joseph Naylor | dnaylor@naylorconstruction.com | (530) 467 3712 | GC, remodel, ADU | Etna · Siskiyou County | — | — |
| Ncf Construction | Kyle Jeffery Rooney | — | (520) 827 0893 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Nelson's Heating And Air INC | Ernest Felix Nelson | service@nelsons-hvac.com | (530) 598 2651 | HVAC | Yreka · Siskiyou County | — | — |
| Network One | Cael Padric Weston | info@networkone.com | (877) 256 2006 | Other | Yreka · Siskiyou County | — | — |
| New Empire Aggregate DBA R K Ricks Construction | Russell Ray Ricks | — | (530) 262 4475 | GC, remodel, ADU | Mount Shasta · Siskiyou County | — | — |
| Next Level Inspections | Next Level Inspections | — | (530) 340-1254 | Inspectors | Yreka · Siskiyou County | — | — |
| Nichols Landscaping | Nichols Landscaping | — | (530) 355 5703 | Windows, patio, painters | Weed · Siskiyou County | — | — |
| Nick Morris Construction | Nicholas Penner Morris | — | (707) 738 0029 | GC, remodel, ADU | Yreka · Siskiyou County | — | — |
| North Coast Painting | David William Moore | — | (530) 999 1394 | Windows, patio, painters | Mc Cloud · Siskiyou County | — | — |
| North Country Electric | James Timothy Calhoun | — | (530) 925 3614 | Electricians | Mt Shasta · Siskiyou County | — | — |
| North Rivers Construction INC | William Raymond Parry | — | (530) 467 3138 | Other | Etna · Siskiyou County | — | — |
| North Wood Construction | Michael William Hunter | — | (530) 925 2514 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Nowdesha Metal Solutions INC | Jacob Allen Nowdesha | — | (530) 459 0170 | Other | Montague · Siskiyou County | — | — |
| Old Etna Tree Services | Jerry Walter Jr Padilla | — | (530) 598 0577 | Tree | Etna · Siskiyou County | — | — |
| Orcal Gutters | Dustin Sean Lockett | — | (530) 410 4395 | Other | Weed · Siskiyou County | — | — |
| P C Pappas Construction | Peter Christopher Pappas | — | (530) 859 0468 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Papa's Construction | Freddie Joseph Gray | — | (530) 938 2238 | GC, remodel, ADU | Weed · Siskiyou County | — | — |