| A-1 Quality Fence | A-1 Quality Fence | — | (805) 208 6931 | Other | Ventura · Ventura County | — | — |
| A-1 Quality Painters | A-1 Quality Painters | — | (909) 456 4561 | GC, remodel, ADU | La Verne · Los Angeles County | — | — |
| A-1 Rain Gutters | Boris Mirko Novakovic | — | (805) 364 2174 | Other | Santa Barbara · Santa Barbara County | — | — |
| A-1 Ray's Air Conditioning & Heating | Ray Vasquez Hernandez | — | (559) 217 9000 | HVAC | Fresno · Fresno County | — | — |
| A-1 Renovations INC | Torian Jerome Jr Dedmon | — | (619) 496 1166 | GC, remodel, ADU | Spring Valley · San Diego County | — | — |
| A-1 Rooter | A-1 Rooter | — | (626) 332 4810 | Other | Covina · Los Angeles County | — | — |
| A-1 Septic Tank Service | Richard Anthony Ricca | — | (707) 937 0496 | Other | Littleriver · Mendocino County | — | — |
| A-1 Septic Tank Service INC | Sarah Nicole Cortez | — | (510) 886 4455 | Other | Hayward · Alameda County | — | — |
| A-1 Services Electrical - Stucco | Jose Mauricio Diaz | — | (510) 274 3060 | Electricians | Hayward · Alameda County | — | — |
| A-1 Sewer Construction | Xavier Noel Ocampo | — | (818) 384 9518 | Other | Sylmar · Los Angeles County | — | — |
| A-1 Smooth & Stucco INC | Hector Javier Salazar | — | (317) 345 2708 | Other | Highland · San Bernardino County | — | — |
| A-1 Speedy Rooter And Plumbing | Edwin Victor Montalvo | — | (714) 249 0422 | Other | Westminster · Orange County | — | — |
| A-1 Stoves Chimney Sweep & Service | Franklin Lee Armstrong | — | (530) 477 1979 | Other | Grass Valley · Nevada County | — | — |
| A-1 Systematic Fire Protection INC | Mario Jr Rubio | — | (510) 514 5684 | Other | Patterson · Stanislaus County | — | — |
| A-1 Total Service Plumbing | Jeffrey Lee Butler | — | (818) 256 0422 | GC, remodel, ADU | Burbank · Los Angeles County | — | — |
| A-1 Tree Serv | A-1 Tree Serv | — | (805) 929 2520 | Tree | Nipomo · San Luis Obispo County | — | — |
| A-1 Tree Service | Joseph Eugene Rogers | — | (760) 983 1933 | Tree | Hesperia · San Bernardino County | — | — |
| A-2-z Services | Michael Nathaniel Austin | — | (925) 323 2872 | GC, remodel, ADU | Concord · Contra Costa County | — | — |
| A-3 Construction INC | Edwin Santana | — | (714) 597 5865 | GC, remodel, ADU | Santa Ana · Orange County | — | — |
| A-a Backflow Testing & Maintenance | Robert Perea | — | (310) 530 6663 | Electricians | Torrance · Los Angeles County | — | — |
| A-a General Contracting And Painting | Johnny Ray Gonzales | — | (858) 967 0048 | GC, remodel, ADU | Pine Valley · San Diego County | — | — |
| A-a Lock & Alarm INC | James Bruce Mac Lachlan | — | (650) 326 9020 | Alarm and generators | Menlo Park · San Mateo County | — | — |
| A-advanced Locksmiths | Kurt Wyatt Smith | — | (858) 277 4358 | Other | San Diego · San Diego County | — | — |
| A-american Plumbing Company | Gregory Mitchell Saenz | — | (949) 355 6770 | Other | Seal Beach · Orange County | — | — |
| A-arbues Construction | Mauricio Alexander Pena Arbues | — | (628) 468 1760 | GC, remodel, ADU | San Francisco · San Francisco County | — | — |
| A-bear Roofing | Matthew Richard Hebert | — | (805) 299 5616 | Other roofers | Ventura · Ventura County | — | — |
| A-bell Alarms Company | Christopher Gene Sizemore | info@abellalarms.com | (951) 302 3100 | Electricians | Temecula · Riverside County | — | — |
| A-best Construction Corporation | Roberto Lee Uy | — | (818) 349 1308 | GC, remodel, ADU | Northridge · Los Angeles County | — | — |
| A-c And D-c Electric | Cardenas Arthur | — | (626) 366 0483 | Electricians | West Covina · Los Angeles County | — | — |
| A-C Electric | A-C Electric | — | (559) 233-2208 | Electricians | Fresno · Fresno County | — | — |
| A-c Electric Company | Kenneth Michael Byrum | — | (661) 410 0000 | Electricians | Bakersfield · Kern County | — | — |
| A-cal Trim INC | Michael Wayne Stallings | — | (209) 479 9737 | GC, remodel, ADU | Woodbridge · San Joaquin County | — | — |
| A-class Heating And Air | Nikolay P Petrashishin | — | (916) 342 9108 | HVAC | Rancho Cordova · Sacramento County | — | — |
| A-coalescence LLC | Rudy Cortez Valle | — | (951) 318 0167 | Other | Riverside · Riverside County | — | — |
| A-cp Rocker's Plumbing Service | Fortino Armando Franco Gonzalez | — | (213) 572 7206 | Other | Los Angeles · Los Angeles County | — | — |
| A-ction Asphalt | A-ction Asphalt | — | (760) 703 7886 | Other | Menifee · Riverside County | — | — |
| A-custom Construction Company | Ronald Albert Esche | — | (831) 818 1323 | GC, remodel, ADU | Santa Cruz · Santa Cruz County | — | — |
| A-d Plastering INC | La Cruz Anastacio De | — | (209) 263 1985 | Other | Galt · Sacramento County | — | — |
| A-drains Plumbing | A-drains Plumbing | — | (844) 237 2467 | Other | Bellflower · Los Angeles County | — | — |
| A-drains Plumbing And Rooter INC | Adrian Junior Gonzalez | — | (844) 237 2467 | Other | Bellflower · Los Angeles County | — | — |