| A & O Engineering Construction INC | Albert Eugene Allen | — | (714) 915 9135 | Other | Corona · Riverside County | — | — |
| A & R Steel Fab INC | Ricardo Valencia Tapia | — | (951) 278 4680 | Other | Norco · Riverside County | — | — |
| A & S Aquatic Solutions INC | Marco A Cisneros-moyao | — | (951) 454 9405 | Pool | Corona · Riverside County | — | — |
| A & S Electric | Steven Joseph Anderson | — | (951) 751 2767 | Electricians | Hemet · Riverside County | — | — |
| A & Y Asphalt Contractors INC | Jedidiah John Giese | — | (951) 340 4190 | Other | Norco · Riverside County | — | — |
| A + Air Conditioning And Heating | Alvarez Sergio | — | (760) 601 4705 | HVAC | Indio · Riverside County | — | — |
| A + Builders | A + Builders | — | (909) 322 1595 | GC, remodel, ADU | Jurupa Valley · Riverside County | — | — |
| A + Drapes & Blinds | A + Drapes & Blinds | — | (951) 805 7796 | Other | Perris · Riverside County | — | — |
| A - 1 Restoration & Repair INC | Gerri Jo Chambers | — | (760) 568 6672 | Restoration | Palm Springs · Riverside County | — | — |
| A - 1 Window Tinting | A - 1 Window Tinting | — | (760) 773 9958 | Other | Palm Desert · Riverside County | — | — |
| A - Ford - Able Builders | David James Ford | — | (619) 277 3170 | GC, remodel, ADU | Hemet · Riverside County | — | — |
| A - N - W Construction INC | Brian Clifton Gore | — | (951) 354 6924 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| A - Team Tile And Stone | Anthony Gabriel Martinez | — | (760) 673 9561 | Other | Indio · Riverside County | — | — |
| A - Tech Electric | Marco Antonio Pineda | — | (951) 300 6973 | Electricians | Moreno Valley · Riverside County | — | — |
| A - Tek Mechanical INC | Curly Khamla Phom | — | (619) 944 8757 | HVAC | Murrieta · Riverside County | — | — |
| A / B Plastering | A / B Plastering | — | (951) 545 1523 | Other | Moreno Valley · Riverside County | — | — |
| A / C Solutions INC | Casey Al Hudson | — | (951) 448 3432 | HVAC | Murrieta · Riverside County | — | — |
| A 1 Granite + Stone INC DBA A 1 Granite Stone Tile | Jose Coronado | — | (714) 366 5034 | Other | Lake Elsinore · Riverside County | — | — |
| A 2 Z Home Builders INC | Jeffrey Ruiz | — | (951) 453 1889 | GC, remodel, ADU | Perris · Riverside County | — | — |
| A A A Construction | Kevin Deon Askier | yuriy@aaaconstruction.com | (951) 314 8429 | GC, remodel, ADU | Norco · Riverside County | — | — |
| A A A Glass Company | Timothy Carlyn Strom | — | (951) 296 6217 | Windows, patio, painters | Temecula · Riverside County | — | — |
| A A A Landscape Concepts | A A A Landscape Concepts | — | (760) 501 9494 | Windows, patio, painters | Indio · Riverside County | — | — |
| A A Electric | Arthur Daniel Diaz | — | (909) 838 1814 | Electricians | Riverside · Riverside County | — | — |
| A A General Construction | Arturo Cesar Leal Mata | info@aageneralconstruction.com | (951) 349 5226 | GC, remodel, ADU | Jurupa Valley · Riverside County | — | — |
| A A Glazing Company INC | Ayub Adil | — | (562) 452 9464 | Windows, patio, painters | Corona · Riverside County | — | — |
| A A I C Construction | Adib Salem Elnabbout | — | (562) 228 9390 | GC, remodel, ADU | Corona · Riverside County | — | — |
| A A Masonry | Alfredo Alvidrez | — | (760) 360 7388 | Other | Palm Desert · Riverside County | — | — |
| A A Max Quality Construction | Antonio Marco Aguilar | — | (760) 844 4045 | GC, remodel, ADU | Thousand Palms · Riverside County | — | — |
| A B C Electric | Leszek Kazimierz Kondratczyk | — | (949) 254 0863 | Electricians | Palm Desert · Riverside County | — | — |
| A B C Parking Lot Maintenance INC | Hanko Ladehoff | — | (951) 270 2900 | Other | Corona · Riverside County | — | — |
| A B Construction | Balderas Alexander | — | (760) 861 8511 | GC, remodel, ADU | Cathedral City · Riverside County | — | — |
| A B Electric | Antonio Quincoses Brache | — | (310) 612 1650 | Electricians | Murrieta · Riverside County | — | — |
| A B Fence Company INC | Alberto Gutierrez Bedolla | — | (844) 707 0007 | Other | Beaumont · Riverside County | — | — |
| A B G Construction | Alberto Bernardo Gutierrez | — | (951) 906 5202 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| A B Glasswerks & Aluminum | Breana Leigh Rodriguez | — | (562) 375 1544 | Windows, patio, painters | Winchester · Riverside County | — | — |
| A B I Plumbing | A B I Plumbing | — | (760) 879 5856 | Other | Thermal · Riverside County | — | — |
| A B Landscape | A B Landscape | — | (760) 877 1509 | Windows, patio, painters | Temecula · Riverside County | — | — |
| A B M Painting And Wallcovering Corp | Carlos Manuel Flores | — | (951) 603 0369 | Windows, patio, painters | Corona · Riverside County | — | — |
| A B O Electric Services INC | Antonio Brito | — | (562) 446 5715 | Electricians | Moreno Valley · Riverside County | — | — |
| A B S Sandblasting | A B S Sandblasting | — | (760) 770 6837 | Windows, patio, painters | Cathedral City · Riverside County | — | — |