| Bj Construction | Brian Kyun Kyo Jung | — | (949) 556 6131 | GC, remodel, ADU | Irvine · Orange County | — | — |
| Bjh Construction | Brian James Haahr | — | (714) 863 5874 | GC, remodel, ADU | Orange · Orange County | — | — |
| Bjm General Contractor Co | David Ku Jung | — | (714) 341 9552 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Bjp Electric | Bruno Joseph Jr Paquette | — | (949) 413 5556 | Electricians | Laguna Niguel · Orange County | — | — |
| Bjskm INC | Janet Marie Mcdaniel | — | (714) 794 7492 | GC, remodel, ADU | Westminster · Orange County | — | — |
| Bk Construction | Andoh-kesson Benjamin | — | (714) 884 2905 | GC, remodel, ADU | Tustin · Orange County | — | — |
| Bk Engineering Corporation | Clare Patricia Katebian | — | (949) 842 0072 | HVAC | Laguna Niguel · Orange County | — | — |
| Bk Painting INC | Byoungkuk Oh | — | (714) 321 7083 | Windows, patio, painters | Cypress · Orange County | — | — |
| Bk Plumbing INC | Billy Duane Williams | — | (760) 686 1213 | Other | Los Alamitos · Orange County | — | — |
| Bk Roofing And Sons INC | Robert Patrick Kirkhill | — | (714) 756 0570 | Other roofers | Huntington Beach · Orange County | — | — |
| Bkd Electric INC | Bakari Kenneth Diaz | — | (657) 200 0462 | Electricians | Anaheim · Orange County | — | — |
| Bkr Services INC DBA Bkr Construction Services | Jose Alfredo Gomez | — | (949) 279 1761 | GC, remodel, ADU | Westminster · Orange County | — | — |
| Bl Builders INC | Binh Ha Le | — | (714) 264 7690 | GC, remodel, ADU | Westminster · Orange County | — | — |
| Bl Cunningham Enterprises | Bradford Irwin Cunningham | — | (949) 456 6253 | GC, remodel, ADU | Lake Forest · Orange County | — | — |
| Bl Glassworks | Bl Glassworks | — | (949) 484 3011 | Windows, patio, painters | Laguna Niguel · Orange County | — | — |
| Black Bird Fire Protection INC | Richard John Eyssallenne | — | (714) 462 6095 | Electricians | Brea · Orange County | — | — |
| Black Diamond Builds & Renovations INC | Nathan Andrew Do | — | (657) 833 2527 | GC, remodel, ADU | Westminster · Orange County | — | — |
| Black Diamond INC | John Douglas Doan | — | (949) 289 5393 | GC, remodel, ADU | Laguna Hills · Orange County | — | — |
| Black Diamond Waterproofing | Stephen Paul Zens | — | (949) 563 0966 | Other roofers | Lake Forest · Orange County | — | — |
| Black Hawk Framing INC | La Torre Mercado Jaime De | — | (714) 926 6389 | Other | Costa Mesa · Orange County | — | — |
| Black Oak Construction | Daniel Dusko Ukropina | — | (866) 426 2623 | GC, remodel, ADU | Irvine · Orange County | — | — |
| Black Orchid General Construction | Arash Ghods | — | (949) 444 5624 | GC, remodel, ADU | Laguna Niguel · Orange County | — | — |
| Black Ridge Insulation INC | David Michael Deridder | — | (714) 460 3601 | Other | Anaheim · Orange County | — | — |
| Black Rock Construction Company | William Joseph Jr Goshen | — | (714) 412 3106 | Other | Brea · Orange County | — | — |
| Black Star Paving INC | Keith William Woodside | — | (714) 485 2733 | Other | Yorba Linda · Orange County | — | — |
| Black Tree Remodeling LLC | Michael Jerad Barnett | — | (949) 534 2303 | GC, remodel, ADU | Trabuco Canyon · Orange County | — | — |
| Black-top Construction INC | Jorge Medrano | impallari@gmail.com | (833) 462 5586 | GC, remodel, ADU | Buena Park · Orange County | — | — |
| Blackbird Contracting Services INC | Justin Lloyd Vandercook | — | (714) 602 9353 | Other | Anaheim · Orange County | — | — |
| Blackburn Roofing INC | Nathan Thomas Blackburn | — | (714) 388 7966 | Other roofers | Orange · Orange County | — | — |
| Blackfin Networks | Blackfin Networks | — | (949) 478 0901 | Other | Foothill Ranch · Orange County | — | — |
| Blackline Electric | Ricardo Roncancio | — | (714) 307 9761 | Electricians | Anaheim · Orange County | — | — |
| Blackstar Builders INC | Raymond Ernest Dorame | — | (714) 448 4407 | GC, remodel, ADU | Mission Viejo · Orange County | — | — |
| Blackstar Contractors INC | Daniel Stanley Jr Thompson | — | (949) 252 1244 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| Blackwater Building Co | Rey Roberto Juarez Ochoa | — | (949) 973 4855 | GC, remodel, ADU | San Juan Capistrano · Orange County | — | — |
| Blackwell Plumbing | Blackwell Plumbing | — | (714) 625 5983 | Other | Huntington Beach · Orange County | — | — |
| Blain Construction | Matthew Brian Blain | — | (949) 370 3573 | GC, remodel, ADU | Rancho Mission Viejo · Orange County | — | — |
| Blaine Pecaut Electric | Blaine Michael Pecaut | — | (949) 291 5204 | Electricians | San Clemente · Orange County | — | — |
| Blair Construction | Scott Blair Lietzke | — | (949) 400 9964 | GC, remodel, ADU | Fountain Valley · Orange County | — | — |
| Blair R Jones | Blair R Jones | — | (949) 244 3429 | GC, remodel, ADU | Newport Beach · Orange County | — | — |
| Blake Air Conditioning & Service Co INC | Tara Lucyle Hanna | — | (714) 630 6412 | HVAC | Anaheim · Orange County | — | — |