| Alt Roofing INC | Stanley Edward Jackson | — | (206) 587-6211 | Other roofers | Rancho Cucamonga · San Bernardino County | — | — |
| Alta Insulation & Construction INC | Ruben Andrew Sendejas | — | (909) 717 1566 | GC, remodel, ADU | Fontana · San Bernardino County | — | — |
| Alta Loma Drywall | Alta Loma Drywall | — | (909) 851 4051 | Other | Alta Loma · San Bernardino County | — | — |
| Alta Loma Plumbing | Karen Rae Disario | — | (909) 944 6637 | Other | Rancho Cucamonga · San Bernardino County | — | — |
| Alta Rancho Air - Conditioning & Heating Co | Steven Lee Jirschefske | — | (909) 724 8197 | HVAC | Rancho Cucamonga · San Bernardino County | — | — |
| Altamirano Construction INC | Ismari Altamirano | — | (909) 256 1103 | Other roofers | Grand Terrace · San Bernardino County | — | — |
| Altar Construction | Edmanuel Francesco Garcia | — | (909) 380 4105 | GC, remodel, ADU | Big Bear City · San Bernardino County | — | — |
| Altavista Wall Systems INC | Jose D Ramirez | — | (909) 471 9620 | GC, remodel, ADU | Bloomington · San Bernardino County | — | — |
| Alternative Construction Services | James Patrick Callan | — | (951) 203 5296 | GC, remodel, ADU | Upland · San Bernardino County | — | — |
| Alternative Pools & Spas | Alternative Pools & Spas | — | (951) 203 5296 | Pool | Upland · San Bernardino County | — | — |
| Altmeyer INC | Christopher Robert Altmeyer | — | (909) 337 5788 | Other | Cedar Glen · San Bernardino County | — | — |
| Alton Construction Co | Oscar Dorado Quezada | — | (626) 525 1868 | GC, remodel, ADU | Fontana · San Bernardino County | — | — |
| Alva Concrete Services INC | Jesus Alejandro Alvarado | — | (562) 337 4911 | Other | Adelanto · San Bernardino County | — | — |
| Alvarado Drywall INC | Villalpando Alvarado Humberto | — | (562) 754 1269 | Other | Ontario · San Bernardino County | — | — |
| Alvarado General Builders INC | Rafael Alvarado | — | (909) 938 8153 | GC, remodel, ADU | Chino · San Bernardino County | — | — |
| Alvarez & Sons Plumbing INC | Elias De Jesus Alvarez Ramirez | — | (323) 229 8068 | Other | Hesperia · San Bernardino County | — | — |
| Alvarez Painting | Alvarez Painting | interested@domainmarket.com | (909) 684 3860 | GC, remodel, ADU | Alta Loma · San Bernardino County | — | — |
| Alvarez Plumbing & Rooter | Alvarez Plumbing & Rooter | — | (909) 267 0816 | Other | Montclair · San Bernardino County | — | — |
| Alvaro Orozco Salcido | Alvaro Orozco Salcido | — | (909) 320 1136 | Windows, patio, painters | Hesperia · San Bernardino County | — | — |
| Always Blue Pools LLC | Iohan Salaam Ramirez-Lara | — | (909) 640 9506 | Pool | San Bernardino · San Bernardino County | — | — |
| Always Ready Plumbing And Drain INC | Michael Curtis Baughn | — | (909) 716 8645 | Other | Highland · San Bernardino County | — | — |
| Alx Build And Design INC | Alex Leonardo Carmona | — | (951) 217 4316 | GC, remodel, ADU | Fontana · San Bernardino County | — | — |
| Am - Tec Total Security INC | Jeffrey James Torok | — | (909) 573 4678 | Electricians | Chino · San Bernardino County | — | — |
| Am Innovations Corp DBA Am Innovations Painting | Luis Aurelio Marquez Padilla | — | (909) 331 2555 | Windows, patio, painters | Highland · San Bernardino County | — | — |
| Am Martinez Construction | Alexander James Martinez | — | (909) 246 5428 | GC, remodel, ADU | Upland · San Bernardino County | — | — |
| Am Property Maintenance Plumbing Division | Am Property Maintenance Plumbing Division | — | (760) 265 9028 | Other | Yucca Valley · San Bernardino County | — | — |
| Ama Traffic Loops INC | Allan Michael Alvaro | — | (909) 242 6439 | Electricians | Chino · San Bernardino County | — | — |
| Amador Drywall & Metal Framing | Edward Jeremiah Amador | — | (909) 653 3303 | Other | Victorville · San Bernardino County | — | — |
| Amaro Construction | Anthony Jess Amaro | — | (760) 220 8521 | GC, remodel, ADU | Hesperia · San Bernardino County | — | — |
| Ambak Construction | Bakshi Amrit | amrit@ambakconstruction.com | (714) 403-6348 | GC, remodel, ADU | Ontario · San Bernardino County | — | — |
| Amber Anderson | Amber Anderson | — | (909) 795 4923 | Other | Yucaipa · San Bernardino County | — | — |
| Amber Steel Co | Jason William Auld | inquiry@ambersteel.com | (909) 874 2213 | Other | Rialto · San Bernardino County | — | — |
| Ambrocios Tile | Alejandro Hernandez | — | (323) 247 1351 | Other | Victorville · San Bernardino County | — | — |
| Amc Framing INC | Sean Adam Hale | — | (909) 389 1456 | GC, remodel, ADU | Yucaipa · San Bernardino County | — | — |
| Amc Pro Roofing INC | Salvador Martin Martinez | amcproroofing@gmail.com | (909) 977 2763 | Other roofers | Blue Jay · San Bernardino County | — | — |
| Amcon | Steven Douglas Lowrance | — | (760) 810 1516 | GC, remodel, ADU | Victorville · San Bernardino County | — | — |
| Amended Electric INC | Jay Joseph Medina | amendedelectric@proton.me | (909) 676 3354 | Electricians | Rialto · San Bernardino County | — | — |
| Amer General Engineering Contractor | Amer General Engineering Contractor | — | (909) 336 1771 | Other | Blue Jay · San Bernardino County | — | — |
| Amer General Engineering INC | James Patrick Amer | — | (909) 336 1771 | Other | Blue Jay · San Bernardino County | — | — |
| Amer Rabadi Tile & Stone | Amer Rabadi Tile & Stone | — | (760) 403 5848 | Other | Hesperia · San Bernardino County | — | — |