| Northern United Fence INC | Ramiro Jesus Santivanes | — | (661) 558 4283 | Other | Bakersfield · Kern County | — | — |
| Northwest Construction Services INC | Gary Thomas Hadaway | northwestrenos@gmail.com | (661) 201 6842 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Nova General Engineering | Bryan Matthew Walls | — | (661) 706 3673 | Other | Bakersfield · Kern County | — | — |
| Nu Construction INC DBA Under Construction Co | Heather Christine Underhill | — | (661) 978 5952 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Nuckolls Stepic | Nuckolls Stepic | — | (661) 823 8247 | Other | Tehachapi · Kern County | — | — |
| Nunez & Sons Heating & Air Conditioning INC | Garcia Rafael Nunez | — | (661) 557 5926 | HVAC | Arvin · Kern County | — | — |
| Nunez Concrete & Masonry INC | Kenneth Flores | — | (661) 205 0870 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Nupools | Douglas Lee Kerber | — | (661) 333 6560 | Pool | Bakersfield · Kern County | — | — |
| O & C Construction | Antonio Omar Canales Molina | — | (661) 747 2683 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| O & J Plastering | Jose Navarro | — | (661) 809 6482 | Other | Shafter · Kern County | — | — |
| O J Commercial Refrigeration INC | Alfonso Omar Jimenez Ramirez | — | (818) 355 2614 | HVAC | Bakersfield · Kern County | — | — |
| O'donoghue Construction Company | Timothy James O'donoghue | — | (805) 207 7934 | GC, remodel, ADU | Lake Isabella · Kern County | — | — |
| Oak Valley Appliance | Oak Valley Appliance | — | (661) 443-6005 | HVAC | Tehachapi · Kern County | — | — |
| Oakleaf General Engineering Construction | Steven Wayne Oakleaf | — | (661) 302 5670 | Other | Bakersfield · Kern County | — | — |
| Oasis Air And Solar | Benedict Joseph Dominguez | — | (661) 322 2665 | HVAC | Bakersfield · Kern County | — | — |
| Oasis Air Conditioning INC | Benedict Joseph Dominguez | birmingham@oasisaircon.com | (661) 322 2665 | HVAC | Bakersfield · Kern County | — | — |
| Oasis Pools | Oasis Pools | info@oasis-pools.com | (760) 446 1955 | Windows, patio, painters | Ridgecrest · Kern County | — | — |
| Obelisk Development INC | Gerardo Eduardo Jr Serrano | — | (818) 416 4796 | GC, remodel, ADU | North Edwards · Kern County | — | — |
| Obl Construction LLC | Bautista Oscar Lopez | — | (661) 748 9064 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Occ Engineering | Occ Engineering | — | (760) 793 7463 | Other | Ridgecrest · Kern County | — | — |
| Octavio Torres Construction | Octavio Torres | — | (661) 717 6774 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Oesch Construction & Development | Shem David Oesch | — | (661) 303 3248 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Oildale Glass | Oildale Glass | oildaleglassco@gmail.com | (661) 393 0733 | Windows, patio, painters | Bakersfield · Kern County | — | — |
| Oilfield Work | Howard Edward Caywood | — | (661) 213 3088 | Other | Bakersfield · Kern County | — | — |
| Old Ironsides Construction INC | Lee'o Alan Ii Whisenant | — | (661) 237 7200 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Old Mill Construction LLC | Hector Adrian Gonzalez Rodriguez | — | (661) 497 2365 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Old Ranch Construction INC | Jesus Flores | — | (661) 303 1461 | Electricians | Bakersfield · Kern County | — | — |
| Old Town Plumbing | Old Town Plumbing | — | (661) 221 3799 | Other | Tehachapi · Kern County | — | — |
| Olvera's Construction Services | Romero Roberto Olvera | — | (818) 602 1498 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Olympus Concrete | Eduardo Ramirez | — | (661) 384 9337 | Other | Bakersfield · Kern County | — | — |
| Om Management & Business Associates INC | Billy Joe Mc Cuan | — | (661) 699 5194 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Omega Lathing & Plastering | Omega Lathing & Plastering | — | (623) 203 1319 | Other | Tehachapi · Kern County | — | — |
| Omelchenko Dmytro | Omelchenko Dmytro | — | (661) 201 4271 | HVAC | Bakersfield · Kern County | — | — |
| On Call Air Conditioning And Heating Repair For Less | Diaz Rudy | — | (661) 619 6887 | HVAC | Bakersfield · Kern County | — | — |
| On Point Electric | Philip Harold Abshier | — | (661) 859 3367 | Electricians | Bakersfield · Kern County | — | — |
| Onobi Development And Construction | Smith Adamudu Efada | — | (661) 243 6051 | GC, remodel, ADU | Bakersfield · Kern County | — | — |
| Open & Shut Enterprises | Raymond Joseph Oberlies | — | (661) 587 6200 | Other | Bakersfield · Kern County | — | — |
| Optimal Electric | Wendell M Cruz | andrey@optimal-electric.com | (360) 635-7495 | Electricians | Bakersfield · Kern County | — | — |
| Optimal Heating & Air INC | Alfonso Henry Castellon | — | (661) 319 4258 | HVAC | Bakersfield · Kern County | — | — |
| Optimal Heating And Cooling | Optimal Heating And Cooling | — | (661) 472 1175 | HVAC | Bakersfield · Kern County | — | — |