| Asphalt And Concrete Enterprises INC | John Bret Turley | — | (619) 820 8141 | Other | Santee · San Diego County | — | — |
| Asphalt Maintenance & Paving Company | Randolph Emile Gardini | — | (619) 925 7259 | Other | El Cajon · San Diego County | — | — |
| Asphalt Management & Consulting | Asphalt Management & Consulting | — | (619) 994 6558 | Other | Rancho Santa Fe · San Diego County | — | — |
| Aspire Construction | James Perfecto Galindo | — | (760) 525 8836 | GC, remodel, ADU | Oceanside · San Diego County | — | — |
| Asr Construction | Joe Santino Romero | — | (760) 458 0840 | GC, remodel, ADU | Fallbrook · San Diego County | — | — |
| Assemble Build INC | Richard Allen Jr Clarke | — | (858) 866 6958 | GC, remodel, ADU | Fallbrook · San Diego County | — | — |
| Asset Builders | Joseph Frederick Jr Oliver | — | (858) 560 9363 | GC, remodel, ADU | San Diego · San Diego County | — | — |
| Asset Consulting And Contracting INC | Justin Lloyd Blake | — | (619) 414 7495 | GC, remodel, ADU | La Mesa · San Diego County | — | — |
| Associate Mechanical Contractors INC | Richard Steven| Reinholz Rick Steven Reinholz | — | (760) 294 3517 | HVAC | Escondido · San Diego County | — | — |
| Associated Builder | Associated Builder | — | (619) 246 6423 | GC, remodel, ADU | La Mesa · San Diego County | — | — |
| Associated Facility Services | David James Wines | — | (760) 805 4929 | GC, remodel, ADU | Fallbrook · San Diego County | — | — |
| Associated General Contractors INC | Gerardo Ramirez-Nunez | — | (619) 710 3248 | GC, remodel, ADU | San Diego · San Diego County | — | — |
| Assured Building Services INC | Matthew Armane Miliner | — | (619) 804 8706 | GC, remodel, ADU | Escondido · San Diego County | — | — |
| Astera Construction | Adam Hackel | — | (619) 348 1040 | Other | La Mesa · San Diego County | — | — |
| Astro Building Services | Jose Ricardo Moreno | pscheckler@astrobuildingsvcs.com | (619) 442 9686 | HVAC | El Cajon · San Diego County | — | — |
| Astro Mechanical Contractors INC | Jose Ricardo Moreno | info@astro-mech.com | (619) 442 9686 | HVAC | El Cajon · San Diego County | — | — |
| At Concrete INC | Charles Howard Jr Auge | — | (951) 675 4908 | Other | Fallbrook · San Diego County | — | — |
| At Custom Painting INC | Armando Tlazola | — | (619) 419 7066 | Windows, patio, painters | San Diego · San Diego County | — | — |
| At Home Theater Systems INC | Stephen Salvatore Ambrogio | — | (619) 840 3274 | Other | Carlsbad · San Diego County | — | — |
| At The Junction Construction INC | Carlos Enrique| Penate Chuck E Penate | guy@infinitydesignbuild.com | (760) 855 0552 | Electricians | Escondido · San Diego County | — | — |
| Atala Ecr INC | Anthony Tomas Talamantez | — | (858) 336 0123 | Other | El Cajon · San Diego County | — | — |
| Atek Construction | Maan Abou Atek | — | (760) 715 2328 | GC, remodel, ADU | Escondido · San Diego County | — | — |
| Atel Technologies INC | Steven Eugene Handelman | — | (858) 646 4600 | Electricians | San Diego · San Diego County | — | — |
| Athena Drains & Pipelining | Athena Drains & Pipelining | — | (619) 417 2275 | Other | San Diego · San Diego County | — | — |
| Atherton Construction | John Almond Atherton | — | (951) 692 8938 | GC, remodel, ADU | Lakeside · San Diego County | — | — |
| Athletic Turf Solutions | James Douglas Breeden | — | (619) 316 8804 | Other | Vista · San Diego County | — | — |
| Atila Construction INC | Marquez Atilano | — | (619) 788 2424 | GC, remodel, ADU | San Diego · San Diego County | — | — |
| Atkins Builders INC | Shawn Kenneth Atkins | atkinsbuildersinc@gmail.com | (760) 305 3573 | GC, remodel, ADU | Bonsall · San Diego County | — | — |
| Atlantico Builders | Sergio Oswaldo Gutierrez Garcia | info@atlanticobuilders.com | (619) 762 0463 | GC, remodel, ADU | National City · San Diego County | — | — |
| Atlantis Sealants INC | Lora David | — | (619) 841 8518 | Other | San Diego · San Diego County | — | — |
| Atlantis Tile & Stone | Atlantis Tile & Stone | — | (619) 571 2027 | Other | San Diego · San Diego County | — | — |
| Atlas Construction Corp | Wu Yongchen | — | (858) 262 9409 | GC, remodel, ADU | San Diego · San Diego County | — | — |
| Atlas Crane Service | Clayton Levi Brennick | — | (858) 848 6956 | Other | Lakeside · San Diego County | — | — |
| Atlas Custom Construction INC | Cameron Patrick Arnold | — | (858) 205 0990 | GC, remodel, ADU | Solana Beach · San Diego County | — | — |
| Atlas Development Corporation | Mohammad Hossein Atefi | — | (619) 200 0902 | GC, remodel, ADU | Solana Beach · San Diego County | — | — |
| Atlas Drywall Systems INC | Gildardo Diaz Gomez | — | (760) 504 7486 | Other | Escondido · San Diego County | — | — |
| Atlas Electric | Erfani Mehran | — | (760) 960 6041 | Electricians | Poway · San Diego County | — | — |
| Atlas Elevator Co | Aaron Arnold Ruud | info@latinotype.com | (619) 460 5020 | Other | Spring Valley · San Diego County | — | — |
| Atlas Equipment Company INC | Bonnie Weisser Houston | — | (858) 455 5800 | Other | San Diego · San Diego County | — | — |
| Atlas HVAC INC | Avanesov Vadim | — | (877) 452 8527 | HVAC | San Diego · San Diego County | — | — |