| Lonnie Carruth Construction INC | Lonnie Ray Carruth | — | (530) 864 0370 | GC, remodel, ADU | Cottonwood · Shasta County | — | — |
| Loomis Roofing | Matthew Tyler Loomis | — | (530) 604 4311 | Other roofers | Redding · Shasta County | — | — |
| Lopez Construction | Jose Alfredo Lopez | — | (530) 276 3367 | GC, remodel, ADU | Anderson · Shasta County | — | — |
| Loucks INC DBA Loucks Grading And Water Truck | Stacy Kevin Loucks | — | (530) 227 2194 | Other | Redding · Shasta County | — | — |
| Love Plumbing | Love Plumbing | — | (530) 389 2627 | Other | Redding · Shasta County | — | — |
| Lovell Tree Service | Aaron Justin Lovell | lovellaaron18@gmail.com | (530) 917 7169 | Tree | Anderson · Shasta County | — | — |
| Lucero Construction | Robert Phillip Lucero | hi@typemade.mx | (530) 604 8224 | GC, remodel, ADU | Shasta Lake · Shasta County | — | — |
| Lucio Lopez Maya | Lucio Lopez Maya | — | (818) 454 1222 | Other | Redding · Shasta County | — | — |
| Luis Nunez Construction | Luis Eduardo Nunez | — | (530) 953 8007 | GC, remodel, ADU | Redding · Shasta County | — | — |
| Luke Pearson Construction LLC | Luke Daniel Pearson | — | (530) 605 9575 | GC, remodel, ADU | Oak Run · Shasta County | — | — |
| Lynch Construction | Benjamin Allen Lynch | — | (530) 524 3836 | GC, remodel, ADU | Redding · Shasta County | — | — |
| M & M Hansen Communication's Contracting | Mark Jon Hansen | — | (530) 276 4679 | Other | Palo Cedro · Shasta County | — | — |
| M & M Mobile Welding | M & M Mobile Welding | — | (530) 347 9626 | Other | Cottonwood · Shasta County | — | — |
| M & S Environmental Landscapes INC | Michael Arthur Smith | — | (530) 241 1418 | Windows, patio, painters | Redding · Shasta County | — | — |
| M A S Concrete | M A S Concrete | — | (530) 209 5116 | Other | Anderson · Shasta County | — | — |
| M C Construction | Marcus Alexander Cardenas | — | (530) 410 3218 | GC, remodel, ADU | Palo Cedro · Shasta County | — | — |
| M D B Construction | Michael Daniel Bigley | — | (530) 339 8414 | GC, remodel, ADU | Redding · Shasta County | — | — |
| M D Concrete LP | Rivera Baltazar Rincon | — | (530) 524 9909 | Other | Redding · Shasta County | — | — |
| M D Construction | Michael Anthony Ducazau | — | (530) 949 9634 | GC, remodel, ADU | Palo Cedro · Shasta County | — | — |
| M D I General Contracting | Ray Dale Pedersen | work@millerdoesit.com | (412) 841-2940 | GC, remodel, ADU | Redding · Shasta County | — | — |
| M D Olney Construction | Mark Davin Olney | — | (530) 365 3800 | GC, remodel, ADU | Anderson · Shasta County | — | — |
| M D S Engineering & Construction INC | Michael Shawn Stierli | — | (530) 275 2779 | GC, remodel, ADU | Redding · Shasta County | — | — |
| M D Thurber INC DBA M & J Electric | Justice Anthony Perri | — | (530) 378 5490 | Electricians | Anderson · Shasta County | — | — |
| M G P Builders | M G P Builders | — | (530) 315 3170 | GC, remodel, ADU | Redding · Shasta County | — | — |
| M G Restoration Contracting | Michael Gene Woodley | — | (530) 510 8839 | GC, remodel, ADU | Redding · Shasta County | — | — |
| M S Mors Const | M S Mors Const | — | (530) 549 5469 | GC, remodel, ADU | Palo Cedro · Shasta County | — | — |
| M S Shufelberger Construction | Michael Steven Shufelberger | — | (530) 221 8555 | GC, remodel, ADU | Redding · Shasta County | — | — |
| M White Construction | Kenneth Michael White | — | (530) 524 9621 | Other | Redding · Shasta County | — | — |
| M&b Tree Solution INC | Anguiano Abel Mendoza | — | (530) 407 4388 | Other | Shingletown · Shasta County | — | — |
| M1 Construction | Vang Thai | — | (916) 716 4995 | GC, remodel, ADU | Redding · Shasta County | — | — |
| M3 Unlimited Construction & Landscape | Logan Daniel Miller | — | (530) 524 5931 | GC, remodel, ADU | Shingletown · Shasta County | — | — |
| M4 Construction INC | Tyler Richard Morgan | — | (530) 803 3045 | GC, remodel, ADU | Cottonwood · Shasta County | — | — |
| M5 Excavation | Dominic Ross Marchione | — | (530) 356 6625 | Other | Redding · Shasta County | — | — |
| Maas And Sons Construction A Partnership | James Carl Maas | — | (707) 498 8211 | Electricians | Redding · Shasta County | — | — |
| Mac - Co Metal Buildings | Alan Dale Adkins | — | (530) 365 1403 | GC, remodel, ADU | Anderson · Shasta County | — | — |
| Mac Donald's Landscaping Services | Milton Bernard Mac Donald | — | (530) 262 7803 | Windows, patio, painters | Shasta · Shasta County | — | — |
| Mac Dowell Masonry And Son | Ted Clair Mac Dowell | — | (530) 515 3797 | Other | Redding · Shasta County | — | — |
| Mac's Consulting Service | Brian Patrick Mc Kinnie | — | (707) 318 0926 | GC, remodel, ADU | Burney · Shasta County | — | — |
| Mackney Roofing | Jeffery Lynn Mackney | — | (530) 806 6014 | Other roofers | Redding · Shasta County | — | — |
| Macnair Construction INC | Macnair Construction INC | — | (530) 209 2055 | GC, remodel, ADU | Cottonwood · Shasta County | — | — |