| All Time Pool Plastering INC | Jeffrey Chan| Kang Chan Kyu Kang | — | (714) 590 2261 | Windows, patio, painters | Tustin · Orange County | — | — |
| All Tomorrow's Plumbing | All Tomorrow's Plumbing | — | (714) 290 4701 | Other | Fullerton · Orange County | — | — |
| All Trades Maintenance Services | Matthew Sean Calvert | — | (714) 767 9915 | GC, remodel, ADU | Fullerton · Orange County | — | — |
| All Ways Service | Scott Matthew Neibel | — | (949) 292 9843 | Other | Mission Viejo · Orange County | — | — |
| All-safe Pool Fence & Covers | Helen Jo Ann Hauge | — | (714) 712 6233 | GC, remodel, ADU | Orange · Orange County | — | — |
| All-star Pool Service INC | Dean Charles Becker | — | (949) 222 2425 | Pool | Santa Ana · Orange County | — | — |
| Allan B Steward & Sons | Allan B Steward & Sons | — | (951) 640 3708 | GC, remodel, ADU | San Clemente · Orange County | — | — |
| Allan H Chen | Allan H Chen | — | (949) 248 0583 | GC, remodel, ADU | Capistrano Beach · Orange County | — | — |
| Allan Peterson | Allan Peterson | allanpetersonmusic@gmail.com | (714) 269 5908 | Electricians | Westminster · Orange County | — | — |
| Allan R Tilford General Building Contractor | Allan Raymond Tilford | — | (949) 370 1606 | GC, remodel, ADU | Anaheim · Orange County | — | — |
| Allan Valadez DBA Rescrete | Allan Valadez DBA Rescrete | — | (714) 408 0763 | Other | Newport Beach · Orange County | — | — |
| Allclear Plumbing Pros LLC | Nick Niagolov | — | (949) 758 0203 | Other | Laguna Hills · Orange County | — | — |
| Allegiance 76 Heating And Air Conditioning LLC | Michael Anthony Chumpitazi | — | (562) 405 9205 | HVAC | Anaheim · Orange County | — | — |
| Allegiant Mechanical INC | Zosimo Roxas Zaide | — | (951) 858 4943 | HVAC | Westminster · Orange County | — | — |
| Allegre Custom Construction | Marc Dennis Allegre | — | (714) 606 4499 | GC, remodel, ADU | Huntington Beach · Orange County | — | — |
| Allen Air | Allen Air | — | (714) 337 0667 | HVAC | Anaheim · Orange County | — | — |
| Allen Construction And Design | Ramsey Patrick Allen | — | (949) 307 9892 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| Allen Office INC | Jacob Robert Allen | — | (949) 735 7438 | GC, remodel, ADU | Costa Mesa · Orange County | — | — |
| Allen Othman | Allen Othman | — | (714) 715 2858 | GC, remodel, ADU | Stanton · Orange County | — | — |
| Allen Plumbing And Rooter | Allen Plumbing And Rooter | — | (949) 566 1672 | Other | Costa Mesa · Orange County | — | — |
| Allen Ross Tile Company INC | Allen Gilbert Ross | — | (714) 259 7660 | Other | Laguna Hills · Orange County | — | — |
| Allen V Mclane | Allen V Mclane | — | (949) 687 5388 | Electricians | Coto De Caza · Orange County | — | — |
| Allen Window And Door Glazing LLC | Jason Michael Allen | — | (714) 496 1927 | Windows, patio, painters | Cypress · Orange County | — | — |
| Allen Woodworking INC | Jeffrey Scott Allen | — | (714) 717 6296 | Other | Huntington Beach · Orange County | — | — |
| Allen's Plumbing INC | Nicholas Mark Allen | — | (949) 309 1785 | Other | San Clemente · Orange County | — | — |
| Allende's Group INC | Allende Santiago Torres | — | (949) 619 0844 | Other | Garden Grove · Orange County | — | — |
| Alley Cat Development INC | Ralph Fritz Czarnetzki | — | (714) 501 8453 | GC, remodel, ADU | Huntington Beach · Orange County | — | — |
| Alli Plumbing | Alli Plumbing | — | (714) 326 5287 | Other | Huntington Beach · Orange County | — | — |
| Alliance Cabling INC | Glen Scott Hubocan | — | (714) 549 2299 | Other | Laguna Hills · Orange County | — | — |
| Alliance Contracting | Maxwell Cole Flora | — | (949) 910 3920 | GC, remodel, ADU | Mission Viejo · Orange County | — | — |
| Alliance Electric | Julio Cesar De La O | — | (714) 213 2726 | Electricians | Fullerton · Orange County | — | — |
| Alliance Group Enterprise INC The | Andy Gerald Duong | — | (213) 505 0295 | GC, remodel, ADU | Santa Ana · Orange County | — | — |
| Alliance Heating And Air Conditioning INC | John Robert Tropila | — | (714) 436 1652 | HVAC | Santa Ana · Orange County | — | — |
| Alliance Residential Builders Ii LLC | Residential Builders Ii Alliance | — | (949) 285 5528 | GC, remodel, ADU | Irvine · Orange County | — | — |
| Alliant Garage Door | Victor Jaimie Rocha | — | (714) 410 5700 | Other | Anaheim · Orange County | — | — |
| Allied Builders Group INC | Yasamifar Cyrus | — | (949) 202 8833 | GC, remodel, ADU | Lake Forest · Orange County | — | — |
| Allied Cleanrooms | Cathy Peithman | sales@alliedcleanrooms.com | (714) 922 1576 | GC, remodel, ADU | Orange · Orange County | — | — |
| Allied Development Company | Robert Steven Hertzberg | — | (949) 795 0331 | GC, remodel, ADU | Santa Ana · Orange County | — | — |
| Allied Electric INC | Brandon Loren Bec | — | (714) 232 9197 | Electricians | Brea · Orange County | — | — |
| Allied Engineering & Fire Protection Services | Ghaleh Gholam Hass Rezaei | — | (714) 932 4988 | HVAC | Newport Beach · Orange County | — | — |