| Fletcher Earthwork | Fletcher Earthwork | — | (925) 323 9721 | Other | Mount Shasta · Siskiyou County | — | — |
| Floor It Enterprises | Andrew William Burnett | — | (530) 925 0471 | Other | Mt Shasta · Siskiyou County | — | — |
| Frank's Fuel Oils & Heating | Frank's Fuel Oils & Heating | — | (530) 235 1003 | HVAC | Dunsmuir · Siskiyou County | — | — |
| Ftm Engineering | Wyatt David Monday | — | (530) 643 1226 | Other | Fort Jones · Siskiyou County | — | — |
| G S Black INC | Gary Paul Black | — | (530) 598 5800 | Other | Etna · Siskiyou County | — | — |
| G.t. Construction | Gregory Travis Lindsey | info@gtconstruction.com | (530) 925 0683 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Gabriel Mc Kinnon Construction | Mc Kinnon Gabriel | — | (530) 351 8737 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Galaxy General Contracting Corporation | Jorge Omar Quiros | — | (805) 825 5134 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Gamache Construction INC | Michael Allen Gamache | — | (530) 643 3207 | GC, remodel, ADU | Mount Shasta · Siskiyou County | — | — |
| Garland Tech | Sean William Garland | — | (530) 988 5200 | Other | Weed · Siskiyou County | — | — |
| Gary Mueller | Gary Mueller | garymuellerinc@gmail.com | (916) 965 0371 | Other | Yreka · Siskiyou County | — | — |
| Gautreaux Construction | Donald Gerald Gautreaux | — | (530) 925 8013 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Geoserv INC | Arley Scott Enloe | — | (530) 471 8899 | Other | Mt Shasta · Siskiyou County | — | — |
| Gerald James Mille | Gerald James Mille | — | (925) 606 8000 | GC, remodel, ADU | Mount Shasta · Siskiyou County | — | — |
| Gerard Pelletier Backhoe & Excavation INC | Gerard Joseph Pelletier | — | (530) 926 2759 | Other | Mt Shasta · Siskiyou County | — | — |
| Gg Construction | Gregory Eugene Ginochio | — | (530) 591 2883 | GC, remodel, ADU | Yreka · Siskiyou County | — | — |
| Gillikin Siding & Framing | Gillikin Siding & Framing | — | (510) 367 0994 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Gillingham Construction Co | Gillingham Construction Co | — | (530) 842-1354 | GC, remodel, ADU | Yreka · Siskiyou County | — | — |
| Gipson Floors | Gipson Floors | — | (530) 261 1940 | Other | Mt Shasta · Siskiyou County | — | — |
| Gk Construction Co | Gage Robert Kinkade | — | (530) 859 0874 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Gold Star Electric & Controls | Veronica Ann Rivera | — | (530) 905 0265 | Electricians | Weed · Siskiyou County | — | — |
| Golden Summit Construction Co | Christopher Michael Scot Jones | — | (530) 925 4885 | GC, remodel, ADU | Mount Shasta · Siskiyou County | — | — |
| Goodwins Contract Crushing | Goodwins Contract Crushing | — | (530) 842 5544 | Other | Yreka · Siskiyou County | — | — |
| Great Northern Services | Laurence Howard Luce | — | (530) 938 4115 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Greenwood Painting LLC | Greenwood Painting LLC | nate@greenwoodpaintingllc.com | (541) 699-2940 | Windows, patio, painters | Yreka · Siskiyou County | — | — |
| Gregory Construction | Gregory J R | — | (530) 926 9114 | GC, remodel, ADU | Weed · Siskiyou County | — | — |
| Gregory Samtob Hunt | Gregory Samtob Hunt | — | (858) 210 1987 | GC, remodel, ADU | Mount Shasta · Siskiyou County | — | — |
| Guy Scott Painting | Guy Scott Painting | — | (530) 842-1373 | Windows, patio, painters | Yreka · Siskiyou County | — | — |
| Happy Feet Flooring Installation And Repair | Daniel Nathan Golubich | — | (970) 231 3029 | Other | Mount Shasta · Siskiyou County | — | — |
| Harry William Shannon | Harry William Shannon | — | (530) 340 4966 | GC, remodel, ADU | Yreka · Siskiyou County | — | — |
| Hart Homes LLC | Ronald William Jr Hart | — | (541) 450 1347 | GC, remodel, ADU | Mount Shasta · Siskiyou County | — | — |
| Hart's Construction Service | Ronald William Hart | — | (530) 261 0704 | GC, remodel, ADU | Mt Shasta · Siskiyou County | — | — |
| Hayes & Sons INC | Jerry Dean Hayes | — | (530) 598 3577 | Other | Montague · Siskiyou County | — | — |
| Heritage Properties | Heritage Properties | management@siskiyouheritageproperties.com | (530) 842-2020 | Property managers | Yreka · Siskiyou County | — | — |
| Hibshman Construction Company | Joel Eric Hibshman | — | (530) 905 3556 | GC, remodel, ADU | Montague · Siskiyou County | — | — |
| High Mountain Plumbing | High Mountain Plumbing | — | (530) 261 0850 | Other | Mt Shasta · Siskiyou County | — | — |
| Highline Plumbing Systems LLC | John Glen Wear | — | (530) 598 1616 | Other | Fort Jones · Siskiyou County | — | — |
| Hitchcock's Construction INC | Terry Lee Hitchcock | — | (530) 964 2512 | Other | Mc Cloud · Siskiyou County | — | — |
| Holy Smoke INC | Sean Glen Kraemer | — | (530) 841 1841 | Other | Yreka · Siskiyou County | — | — |
| Honeyball Construction | Robert Matthew Honeyball | — | (530) 905 0985 | GC, remodel, ADU | Yreka · Siskiyou County | — | — |