| Arw Plumbing | Arw Plumbing | — | (562) 760 0916 | Other | Hemet · Riverside County | — | — |
| Arzel Sheet Metal | Arlexis Efren Alvarado | — | (951) 385 5481 | Other | Moreno Valley · Riverside County | — | — |
| As & Cs Framing | Cesar Enrique Jimenez Lopez | — | (951) 334 3169 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| As Drc | Brett Jay Soliday | — | (760) 724 0454 | GC, remodel, ADU | Temecula · Riverside County | — | — |
| As One Drywall INC | Albert Stuart Salazar | — | (760) 333 5250 | Other | North Palm Springs · Riverside County | — | — |
| Asap Earthwork | Curren Todd Anglin | — | (909) 371 2260 | Other | Calimesa · Riverside County | — | — |
| Asap Plumbing Contractors INC | Salvador Sanchez | — | (951) 790 9046 | Other | Corona · Riverside County | — | — |
| Asap Window And Door Glass LLC | Pedro Herman De Je Mayorga | — | (928) 615 2455 | Windows, patio, painters | Thousand Palms · Riverside County | — | — |
| Asaro Builders INC | Stanley Burton Asaro | — | (760) 776 0043 | GC, remodel, ADU | Palm Desert · Riverside County | — | — |
| Asb Building | Beltran Arturo Salgado | — | (714) 914 8316 | GC, remodel, ADU | Lake Elsinore · Riverside County | — | — |
| Aschoff Construction And Property Maintenance | Richard Bryan Aschoff | — | (562) 458 7578 | GC, remodel, ADU | Mira Loma · Riverside County | — | — |
| Asf Construction | Francisco Fabian Sanchez | — | (951) 238 9668 | GC, remodel, ADU | Moreno Valley · Riverside County | — | — |
| Ashman Masonry INC | Phillip Gordon Ashman | — | (951) 929 1978 | Other | Hemet · Riverside County | — | — |
| Ashoona Landscape | Darrell Lee Johnston | — | (714) 290 3339 | Windows, patio, painters | Murrieta · Riverside County | — | — |
| Aso Pipeline INC | Steven Roman Diaz | — | (909) 438 0767 | Other | Perris · Riverside County | — | — |
| Asp 503 | Asp 503 | — | (951) 378 9904 | Other roofers | Perris · Riverside County | — | — |
| Aspect Air Conditioning & Heating | Aspect Air Conditioning & Heating | — | (310) 874 2038 | HVAC | Murrieta · Riverside County | — | — |
| Aspers Electric | Jon Scott Asper | — | (951) 850 3644 | Electricians | Riverside · Riverside County | — | — |
| Asphalt Concrete Performance | Carlos Manuel Mendoza | — | (951) 478 0531 | Other | Moreno Valley · Riverside County | — | — |
| Asphalt M D's | Gary Duane Butler | — | (760) 863 4500 | Other | Indio · Riverside County | — | — |
| Asphalt Pavement Specialists | Michael Thomas Stanley | — | (951) 796 1942 | Other | Perris · Riverside County | — | — |
| Asphalt Paving Systems INC | Erik Walfred Yoc Bravo | — | (408) 590 8127 | Other | Corona · Riverside County | — | — |
| Asphalt Professional Services INC | Torres-colmenero Javier | — | (951) 817 9908 | Other | Norco · Riverside County | — | — |
| Asphalt Restoration Solutions | Paul Sean Custa | — | (951) 422 9520 | Restoration | Perris · Riverside County | — | — |
| Asr Demolition INC | Chris Aaron Ramirez | — | (909) 446 5066 | Other | Riverside · Riverside County | — | — |
| Associated Construction And Engineering INC | Lawrence Gene Wombles | — | (949) 455 2682 | Other | Temecula · Riverside County | — | — |
| Associated Restaurant Contractors | Randy Russell Rodriguez | — | (909) 622 1615 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Associated Tank Constructors INC | Eduardo Vicente Peralta | — | (949) 299 5766 | Windows, patio, painters | Temecula · Riverside County | — | — |
| Associates Property Landscape Services | Fernando Rojas | — | (760) 899 4438 | Windows, patio, painters | Indio · Riverside County | — | — |
| Assurance Electric | Anthony Duane Leak | — | (951) 440 1921 | Electricians | Temecula · Riverside County | — | — |
| Assure Quality Construction (aqc) | Ochoa Eduardo | — | (951) 234 2381 | GC, remodel, ADU | Temecula · Riverside County | — | — |
| Assured Building & Construction | Ronald Eric Welch | — | (951) 880 8666 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Assured Heating & Air Conditioning Services LLC | Christopher Andrew Dalton | — | (442) 334 7026 | HVAC | Palm Desert · Riverside County | — | — |
| Astro Electric | George Mason Mc Eachran | hello@astroelectric.com | (425) 405-5956 | Electricians | Thermal · Riverside County | — | — |
| Astro Electric | George Mason Mc Eachran | hello@astroelectric.com | (425) 405-5956 | Electricians | Thermal · Riverside County | — | — |
| Astro Plumbing | Astro Plumbing | — | (951) 351 1675 | Other | Riverside · Riverside County | — | — |
| Astro Shutters LLC | Carlos Rafael Jimenez | — | (951) 573 2560 | Other | Riverside · Riverside County | — | — |
| Astromeritis INC | Kevin M Talwar | — | (951) 522 6362 | Windows, patio, painters | Riverside · Riverside County | — | — |
| Astronaut Electric | Gary Alan Dewey | — | (951) 497 0787 | Electricians | Moreno Valley · Riverside County | — | — |
| Astrum Construction | Alexander Solonin | — | (530) 727 8786 | GC, remodel, ADU | Lake Elsinore · Riverside County | — | — |