| American Stainless | American Stainless | — | (909) 257 5747 | Other | Ontario · San Bernardino County | — | — |
| American Star Image Builders LLC | Jesus Leal | — | (702) 305 2429 | GC, remodel, ADU | Victorville · San Bernardino County | — | — |
| American Threat Assessment Consulting INC | David William Clark | — | (909) 941 0300 | Electricians | Rancho Cucamonga · San Bernardino County | — | — |
| American Tree Company | Mathew Thomas| Day Matt Day | — | (760) 503 9000 | Tree | Apple Valley · San Bernardino County | — | — |
| American Vengeance Electronic Security Systems | Karel Mario Martinez | — | (626) 383 0978 | Alarm and generators | Yucaipa · San Bernardino County | — | — |
| American West Coast Security INC | Michael Patrick Miller | — | (909) 902 0166 | Electricians | Chino · San Bernardino County | — | — |
| American West Restoration INC | Troy Dean Lawson | — | (909) 632 5800 | GC, remodel, ADU | Fontana · San Bernardino County | — | — |
| American Wire INC | Bambang Joseph Rahardjanoto | — | (909) 884 9990 | Other | San Bernardino · San Bernardino County | — | — |
| Amerigas Propane L P | Thomas Andrew Read | — | (909) 578 9593 | Other | Mentone · San Bernardino County | — | — |
| Amero Electric | Buda Ioan | — | (714) 343 2107 | Electricians | Chino · San Bernardino County | — | — |
| Amersa Glass LLC | Jose Alexis Rivera | — | (909) 808 2109 | Windows, patio, painters | Fontana · San Bernardino County | — | — |
| Amezcua's Landscaping Care And Design | Amezcua's Landscaping Care And Design | — | (760) 243 8023 | Windows, patio, painters | Adelanto · San Bernardino County | — | — |
| Amfab INC | Janice Ann Moore | — | (951) 201 1782 | Other | Chino Hills · San Bernardino County | — | — |
| Amg Paving Corp | Carlos Alexis Morelos Macias | estimating@amgpaving.com | (909) 919 6758 | Other | Rancho Cucamonga · San Bernardino County | — | — |
| Amh Construction | Monreal Hoffman Alex | — | (909) 695 5401 | GC, remodel, ADU | Fontana · San Bernardino County | — | — |
| Amilcar M Castillo | Amilcar M Castillo | — | (909) 957 2591 | GC, remodel, ADU | Ontario · San Bernardino County | — | — |
| Amins Construction INC | Francisco Amin Vargas | — | (909) 218 9856 | GC, remodel, ADU | Ontario · San Bernardino County | — | — |
| Amir Construction | Amir Mohd Yusof | — | (909) 520 9054 | GC, remodel, ADU | Redlands · San Bernardino County | — | — |
| Amir Ghabrous | Amir Ghabrous | — | (909) 904 9359 | GC, remodel, ADU | Rancho Cucamonga · San Bernardino County | — | — |
| Amj Builders INC | Apolonio Monton Jr Melaya | — | (909) 202 4975 | GC, remodel, ADU | Fontana · San Bernardino County | — | — |
| Amj Builders INC & Melaya Engineering INC Jv | M J Builders INC A | — | (909) 202 4975 | GC, remodel, ADU | Fontana · San Bernardino County | — | — |
| Amj INC | Maria Cruz Rodriguez | — | (909) 342 0635 | Other | Chino · San Bernardino County | — | — |
| Amj Mechanical | Joel Reyes Nunez | — | (909) 678 7727 | HVAC | Ontario · San Bernardino County | — | — |
| Amj Plumbing Specialists Corp | Joe Frank Ruvalcaba | — | (909) 989 0066 | Other | Rancho Cucamonga · San Bernardino County | — | — |
| Amorosano Plumbing Systems | Amorosano Plumbing Systems | — | (909) 496 6545 | Other | Big Bear City · San Bernardino County | — | — |
| Amp Abatement | Amp Abatement | — | (909) 219 1725 | Tree | Running Springs · San Bernardino County | — | — |
| Amp Electrical Solutions LLC | Manuel Daniel Gonzalez | — | (909) 659 3335 | Electricians | Bloomington · San Bernardino County | — | — |
| Amped Electric | Erik Michael Brandt | — | (760) 912 2987 | Electricians | Apple Valley · San Bernardino County | — | — |
| Amphion | Scott Charles Denton | — | (909) 947 7020 | GC, remodel, ADU | Rancho Cucamonga · San Bernardino County | — | — |
| Amr Electric | Andrew Martinez | — | (626) 632 5743 | Electricians | Upland · San Bernardino County | — | — |
| Ams Paving LLC | Joel Batule | — | (909) 357 0711 | Other | Fontana · San Bernardino County | — | — |
| Ams Restoration INC | Antonio Andre Reed | — | (909) 240 6440 | GC, remodel, ADU | Chino · San Bernardino County | — | — |
| Amy Y Medina | Amy Y Medina | — | (760) 808 1348 | GC, remodel, ADU | Morongo Valley · San Bernardino County | — | — |
| Amz Detailed Painting INC | Zepeda Alexis Morales | — | (909) 680 5018 | Windows, patio, painters | Chino · San Bernardino County | — | — |
| Amz Plumbing INC | Daniel Macias | — | (909) 708 5037 | Other | Montclair · San Bernardino County | — | — |
| Anda | A N D A | — | (909) 226 6562 | GC, remodel, ADU | Ontario · San Bernardino County | — | — |
| Andaloro Tile | Andaloro Tile | — | (951) 269 0043 | Other | Apple Valley · San Bernardino County | — | — |
| Andalusian INC | Felix Lee | — | (626) 255 5899 | GC, remodel, ADU | Chino Hills · San Bernardino County | — | — |
| Andean Construction | Victor Martin Pinedo Chomba | — | (323) 830 5206 | GC, remodel, ADU | Chino Hills · San Bernardino County | — | — |
| Andean Electric | Victor Martin Pinedo Chomba | — | (323) 830 5206 | Electricians | Chino Hills · San Bernardino County | — | — |