| Blackgold Oil Spreading | Corey Robert Kirschner | — | (909) 563 8242 | Other | Rancho Cucamonga · San Bernardino County | — | — |
| Blackhorse Roofing INC | Luis Alberto Garcia | — | (909) 559 4924 | Other roofers | Rialto · San Bernardino County | — | — |
| Blackstone Technologies | Kristopher Kevin Bill | — | (951) 233 4141 | GC, remodel, ADU | Fontana · San Bernardino County | — | — |
| Blacktop Seal Coat And Line Striping | Justin Joseph Buck | — | (909) 559 9988 | Other | Fontana · San Bernardino County | — | — |
| Blackwell Development INC | Jerry | — | (909) 797 0988 | GC, remodel, ADU | Yucaipa · San Bernardino County | — | — |
| Blak Spike Rail INC | Trevor Dean Williams | — | (626) 826 2120 | Other | Rancho Cucamonga · San Bernardino County | — | — |
| Blake Slater | Blake Slater | — | (909) 822 6800 | Other | Fontana · San Bernardino County | — | — |
| Blannon Construction | Earl Leon Blannon | — | (909) 626 2742 | GC, remodel, ADU | Montclair · San Bernardino County | — | — |
| Blazer Electric LLC | David Christopher Lopez | — | (562) 330 0325 | Electricians | Fontana · San Bernardino County | — | — |
| Blinds Express INC | Trish Ann Sole | — | (760) 241 2001 | Other | Victorville · San Bernardino County | — | — |
| Block By Block INC | Laura Ann Howells | — | (760) 486 4052 | Other | Apple Valley · San Bernardino County | — | — |
| Blok Modular Constructors INC | Frederick Faraon Rienton | — | (888) 256 5663 | GC, remodel, ADU | Upland · San Bernardino County | — | — |
| Blue Anchor Plumbing | Blue Anchor Plumbing | — | (909) 734 7325 | Other | San Bernardino · San Bernardino County | — | — |
| Blue Collar Contractor INC | Sean Christopher Payan | — | (562) 418 7580 | Electricians | Upland · San Bernardino County | — | — |
| Blue Haven Pools | Ronald Robert Grijalva | — | (909) 947 6474 | GC, remodel, ADU | Ontario · San Bernardino County | — | — |
| Blue Level General Contractor | Carlos Gerardo Guevara Vazquez | — | (909) 714 8115 | GC, remodel, ADU | Fontana · San Bernardino County | — | — |
| Blue Maple Construction | Vargas Roberto | — | (909) 727 0984 | GC, remodel, ADU | Phelan · San Bernardino County | — | — |
| Blue Marlin Pool & Spa Service | Laurence Bernard Ii Eckel | — | (714) 984 4899 | Pool | Redlands · San Bernardino County | — | — |
| Blue Painting LLC | Sally Ayhala Jimenez Robledo | — | (831) 643 5144 | Windows, patio, painters | Phelan · San Bernardino County | — | — |
| Blue Paradise Custom Pools INC | Luis Fernando Rodriguez Vazquez | — | (909) 471 9229 | Pool | Oak Hills · San Bernardino County | — | — |
| Blue Ribbon Engineering | Casey Thomas Spolar | — | (951) 396 8467 | Other | Oak Hills · San Bernardino County | — | — |
| Blue Sky Construction Co | John Andrew Smith | — | (951) 236 3081 | GC, remodel, ADU | Lake Arrowhead · San Bernardino County | — | — |
| Blue Sky Construction Services | Michael James Chavira | — | (909) 591 7153 | GC, remodel, ADU | Chino · San Bernardino County | — | — |
| Blue Sky Painting Service | Ruiz Carlos | — | (909) 252 9671 | Windows, patio, painters | Rialto · San Bernardino County | — | — |
| Blue Top INC | Joseph Anthony Prieur | — | (951) 805 3555 | Other | Apple Valley · San Bernardino County | — | — |
| Blue Water Pools & Spas | Daniel Frank Gaudy | — | (909) 322 0526 | Pool | Upland · San Bernardino County | — | — |
| Blue Whale Pool & Spa Remodeling | Castillo Ramon Gonzalez | — | (909) 717 8736 | Pool | Ontario · San Bernardino County | — | — |
| Bluecell Energy | Bluecell Energy | support@bluecellenergy.com | (215) 866 7096 | Electricians | Rancho Cucamonga · San Bernardino County | — | — |
| Bluegrass Landscape & Irrigation | Meza Hugo Avalos | — | (909) 545 0474 | Windows, patio, painters | Montclair · San Bernardino County | — | — |
| Blueline Pool Construction | Juan Jr Villalpando | — | (909) 313 7911 | Pool | Ontario · San Bernardino County | — | — |
| Bluepoint Pools | Omar Isai Becerra Alcaraz | bluepointpools@gmail.com | (909) 379 5306 | Pool | Rancho Cucamonga · San Bernardino County | — | — |
| Blueprint Kitchen And Bath Design Studio LLC | Jake Iv Blasco | — | (310) 880 0573 | GC, remodel, ADU | Redlands · San Bernardino County | — | — |
| Bluesky Mechanical Heating & Air Conditioning | Walter Omar Candela | — | (909) 530 0441 | HVAC | Rancho Cucamonga · San Bernardino County | — | — |
| Bluetone Painting | Bluetone Painting | hello@bluetonepainting.com | (951) 233-8593 | Windows, patio, painters | Bloomington · San Bernardino County | — | — |
| Blum Electric | David Todd Blum | info@www.www.blumelectric.com | (909) 307 6333 | Electricians | Yucaipa · San Bernardino County | — | — |
| Blusky Restoration Riverside | Blusky Restoration Riverside | — | (800) 266-5677 | Restoration | Grand Terrace · San Bernardino County | — | — |
| Bmi Construction | Arnoldo Horacio Korsich | — | (818) 618 8380 | GC, remodel, ADU | Rialto · San Bernardino County | — | — |
| Bmk Precision Welding LLC | Tamas Bryan Gyorfi | — | (909) 255 2890 | Other | Yucaipa · San Bernardino County | — | — |
| Boadway Electric INC | David Dwight Ii Boadway | — | (951) 543 3145 | Electricians | San Bernardino · San Bernardino County | — | — |
| Boal Electric | Shad Kjeild Boal | — | (909) 565 8571 | Electricians | Grand Terrace · San Bernardino County | — | — |