| A+ Structures INC | Todd Anthony Schneider | — | (909) 322 1595 | GC, remodel, ADU | Jurupa Valley · Riverside County | — | — |
| A-1 Construction & Landscaping INC | Michael David Peryea | — | (951) 658 7434 | GC, remodel, ADU | Hemet · Riverside County | — | — |
| A-bell Alarms Company | Christopher Gene Sizemore | info@abellalarms.com | (951) 302 3100 | Electricians | Temecula · Riverside County | — | — |
| A-coalescence LLC | Rudy Cortez Valle | — | (951) 318 0167 | Other | Riverside · Riverside County | — | — |
| A-ction Asphalt | A-ction Asphalt | — | (760) 703 7886 | Other | Menifee · Riverside County | — | — |
| A-g Sod Farms INC | John William Addink | — | (951) 687 7581 | Windows, patio, painters | Riverside · Riverside County | — | — |
| A-one Concrete Resurfacing | A-one Concrete Resurfacing | — | (760) 844 0056 | Other | Thousand Palms · Riverside County | — | — |
| A-one Patios | A-one Patios | — | (951) 805 1235 | GC, remodel, ADU | Menifee · Riverside County | — | — |
| A-plus Construction | Anita Dannette Mafoa | — | (951) 354 2454 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| A-s-z Construction INC | Alberto Zatarain | — | (760) 898 1612 | GC, remodel, ADU | Palm Desert · Riverside County | — | — |
| A-team Drains INC | Marcos Aquino | — | (760) 844 0296 | Other | Desert Hot Springs · Riverside County | — | — |
| A-tek Construction | Ace Pekoanthony Aumoeualogo | — | (951) 221 7174 | GC, remodel, ADU | Murrieta · Riverside County | — | — |
| A1 - Electric | Juan Carlos Jimenez | — | (951) 662 8884 | Electricians | Lake Elsinore · Riverside County | — | — |
| A1 Custom Painting | A1 Custom Painting | — | (760) 464 9807 | Windows, patio, painters | La Quinta · Riverside County | — | — |
| A1 Maintenance & Construction Corp | Jacob Daniel Chagolla | — | (951) 518 2415 | GC, remodel, ADU | Temecula · Riverside County | — | — |
| A1 Quality Roofing INC | Armando Esquivel Echevarria | — | (951) 808 4251 | Other roofers | Corona · Riverside County | — | — |
| A1 Solar Consulting LLC | Cesar Ivan Izaguirre | — | (888) 993 3354 | Other roofers | Riverside · Riverside County | — | — |
| A2z Home Improvement Construction Co | Antonio Saldivar Zuniga | — | (909) 615 7979 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| A4welding Structural Steel | Alvaro Leonel Sr Martinez | — | (951) 850 3030 | Other | Riverside · Riverside County | — | — |
| Aa Color Solutions | Aa Color Solutions | — | (951) 834 2615 | Windows, patio, painters | Murrieta · Riverside County | — | — |
| Aa Design Construction | Armen Richard Altounian | — | (760) 272 4285 | GC, remodel, ADU | La Quinta · Riverside County | — | — |
| Aa Traffic | Maria Guadalupe Arredondo Alcantara | — | (951) 356 5878 | Other | Corona · Riverside County | — | — |
| Aa Trusted Construction INC | Flores Hernandez Bryan | — | (951) 435 5152 | GC, remodel, ADU | Homeland · Riverside County | — | — |
| Aaa Arroyo Air Comfort | Norman Dale Green | — | (951) 371 0660 | HVAC | Norco · Riverside County | — | — |
| Aaa Best Gutters | Dale William Butler | — | (714) 693 1400 | Other | Corona · Riverside County | — | — |
| Aaa Painting Company | John Joseph Jr Patterson | — | (951) 685 1595 | Windows, patio, painters | Riverside · Riverside County | — | — |
| Aaa Plumbing Heating And Air Conditioning INC | Ryan Thomas Ballard | — | (951) 780 2513 | HVAC | Riverside · Riverside County | — | — |
| Aaa Pool And Spas INC | Argelia Alfaro | — | (909) 609 8918 | Pool | Jurupa Valley · Riverside County | — | — |
| Aaa Restoration & Cleanning Services | Sepi Ioan Paris | — | (951) 227 1088 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Aaa Roofing And Waterproofing LLC DBA Aaa Roofing | Tyler James Vaske | — | (951) 823 0213 | Other roofers | Riverside · Riverside County | — | — |
| Aaa Roofing And Waterproofing Llc. | Aaa Roofing And Waterproofing Llc. | — | (866) 485-6812 | Other roofers | Riverside · Riverside County | — | — |
| Aaa Tree Service | Frank Arellanes Manqueros | — | (909) 973 2334 | GC, remodel, ADU | Menifee · Riverside County | — | — |
| Aaj Electric LLC | Jose Luis Suazo | — | (951) 339 6440 | Electricians | Riverside · Riverside County | — | — |
| Aaron B Cook Construction | Aaron Bradford Cook | — | (951) 807 7252 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Aaron G Gilbert | Aaron G Gilbert | — | (760) 404 7316 | Electricians | Thousand Palms · Riverside County | — | — |
| Aaron Guzman | Aaron Guzman | — | (951) 642 7268 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Aaron Hatfield | Aaron Hatfield | — | (951) 283 4131 | Electricians | Corona · Riverside County | — | — |
| Aas Sanitation | Aas Sanitation | — | (951) 722 6402 | Other | Perris · Riverside County | — | — |
| Aashiyana Builders | Aashiyana Builders | — | (562) 458 4252 | GC, remodel, ADU | Eastvale · Riverside County | — | — |
| Ab Coatings Inc. | Jose Carlos Avelar | — | (626) 261 5526 | Windows, patio, painters | Riverside · Riverside County | — | — |