| Nor - Cal Floor Design INC | Matthew James Vannoy | info@norcalfloordesign.com | (530) 582 4437 | Other | Truckee · Nevada County | — | — |
| Norcal Excavation | Norcal Excavation | — | (530) 575 2792 | Other | Rough And Ready · Nevada County | — | — |
| Nord Wood House LLC | Dmitry P Eremin | — | (530) 404 5527 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| North - West Construction | Mark Romuald Welcel | — | (530) 906 6565 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| North Lake Construction LLC | Michael Robert Scrivano | — | (530) 606 0045 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| North Pacific Construction | Bruce E Stewart | — | (530) 305 5086 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| North Star Construction Company | Lawrence Maxwell Beck | — | (530) 263 3976 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| North Star Construction Services | Timothy Patrick Horner | — | (530) 470 3861 | GC, remodel, ADU | Nevada City · Nevada County | — | — |
| Northern Sky Builders | Northern Sky Builders | — | (530) 448 6516 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| Northern-air HVAC INC | Andrew Tyrone Souza | — | (530) 268 1480 | HVAC | Grass Valley · Nevada County | — | — |
| Northstar Electric LLC | Timothy Tom Montes | — | (530) 648 0777 | Electricians | Grass Valley · Nevada County | — | — |
| Northwest Sequoia Construction Company | Keith Clark Kesel | — | (530) 575 2384 | GC, remodel, ADU | Nevada City · Nevada County | — | — |
| Northwoods Tree Service | Ryan Michael Guay | — | (530) 575 0599 | Tree | Grass Valley · Nevada County | — | — |
| Np Excavating | Np Excavating | — | (530) 305 6206 | Other | Nevada City · Nevada County | — | — |
| Nunez Painting | Nunez Painting | — | (530) 559 5802 | Windows, patio, painters | Grass Valley · Nevada County | — | — |
| Nunnink Construction | Don Robert Nunnink | — | (530) 320 0758 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| Nxt Lvl Construction INC | Chet Allen Luedtke | — | (530) 448-3036 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| O'brien Painting | O'brien Painting | — | (925) 383 3431 | Windows, patio, painters | Penn Valley · Nevada County | — | — |
| Oakwood Custom Building Company | Bryce William Bartlett | — | (530) 208 5624 | GC, remodel, ADU | Nevada City · Nevada County | — | — |
| Ohnstad Plumbing | Ohnstad Plumbing | — | (530) 210 3285 | Other | Truckee · Nevada County | — | — |
| Old Town Innovations INC DBA Old Town Construction | Juan Enrique Espinoza Cervantes | — | (530) 386 5671 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| Old Town Landscape INC | Alejandro Espinoza | — | (530) 414 4011 | Windows, patio, painters | Truckee · Nevada County | — | — |
| Old Town Sealing | Old Town Sealing | oldtown530@outlook.com | (530) 401 2622 | Other | Truckee · Nevada County | — | — |
| Olinger Construction | Michael John Olinger | — | (415) 740 5580 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| Olivas Construction | Juan Jose Olivas | — | (530) 414 4026 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| Olson Industries | Olson Industries | — | (530) 913 3487 | Windows, patio, painters | Nevada City · Nevada County | — | — |
| Omega Electrical Safety Systems | Jeffrey James Alexander | — | (530) 557 5037 | Electricians | Grass Valley · Nevada County | — | — |
| Omid Heating & Air Conditioning | Alireza Homayouni Afshartabar | — | (530) 270 9092 | HVAC | Penn Valley · Nevada County | — | — |
| Optimal Ag Solutions LLC | Brian Keith Malin | — | (530) 362 0364 | Windows, patio, painters | Grass Valley · Nevada County | — | — |
| Orcino Tile INC | Jeffrey Paul Orcino | — | (530) 913 6247 | Other | Grass Valley · Nevada County | — | — |
| Orea Roofing INC | San Juan Leonardo Orea | — | (775) 354 9411 | Other roofers | Truckee · Nevada County | — | — |
| Orest Prodanivk Const | Orest Prodanivk Const | — | (530) 412 2883 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| Oscar Santana Herrera-mejorado | Oscar Santana Herrera-mejorado | — | (530) 386 4696 | Other | Truckee · Nevada County | — | — |
| Outerlands Design INC | Jared Eric Johnson | jared@outerlandsdesign.com | (415) 987 4302 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| Over The Edge Productions | Over The Edge Productions | — | (530) 575 6204 | Other | Grass Valley · Nevada County | — | — |
| Owner Assisted Remodeling | Owner Assisted Remodeling | — | (530) 913 0801 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| P H Construction | Patrick Edward Hayden | — | (530) 263 1196 | GC, remodel, ADU | Grass Valley · Nevada County | — | — |
| P R D Construction | Mathew Paul Parisi | — | (530) 448 3282 | GC, remodel, ADU | Truckee · Nevada County | — | — |
| P W Morgan Painting | P W Morgan Painting | — | (530) 305 2650 | Windows, patio, painters | Cedar Ridge · Nevada County | — | — |
| Pacific Crest Construction | James Joseph Colborn | — | (530) 448 6361 | GC, remodel, ADU | Truckee · Nevada County | — | — |