| All American Waterproofing INC | John Steve Mondino | — | (650) 366 1161 | Other roofers | Woodside · San Mateo County | — | — |
| All Bay Builders Performance | Yaakobi Noam | — | (408) 482 5861 | HVAC | Menlo Park · San Mateo County | — | — |
| All Bay Marble Design | All Bay Marble Design | — | (650) 578 0349 | Other | San Mateo · San Mateo County | — | — |
| All Fence Company INC | Martin Anthony Webster | info@allfence.com | (650) 369 4556 | GC, remodel, ADU | Redwood City · San Mateo County | — | — |
| All Garden INC | Pedro Garcia-Renova | — | (650) 333 9494 | Windows, patio, painters | Redwood City · San Mateo County | — | — |
| All Good Excavator And Demolition | All Good Excavator And Demolition | — | (650) 295 9365 | Other | San Mateo · San Mateo County | — | — |
| All Ornamental & Custom Ironworks | All Ornamental & Custom Ironworks | — | (650) 218 0223 | Other | San Carlos · San Mateo County | — | — |
| All Phase Builders | All Phase Builders | — | (650) 508 8485 | GC, remodel, ADU | San Carlos · San Mateo County | — | — |
| All Pro Painting | All Pro Painting | — | (650) 208 6897 | Windows, patio, painters | Belmont · San Mateo County | — | — |
| All Pro Painting LLC | Nisrine Mekhael Makhlouf | — | (650) 208 0009 | Windows, patio, painters | Belmont · San Mateo County | — | — |
| All Roofing Solutions | Luis Manuel Pina Perez | info@allroofingsolutions.com | (650) 720 2133 | Other roofers | Redwood City · San Mateo County | — | — |
| All Star Flooring INC | Fierros Antonio Romero | — | (650) 503 8554 | Other | San Carlos · San Mateo County | — | — |
| All Surface Wash INC | David Peter Jr Lopez | — | (415) 316 8780 | Other | South San Francisco · San Mateo County | — | — |
| All Type Flooring | All Type Flooring | — | (415) 279 6317 | Other | Burlingame · San Mateo County | — | — |
| All Weather Construction | Patrick Browne | — | (650) 290 0592 | GC, remodel, ADU | Pacifica · San Mateo County | — | — |
| All Wood Floors INC | Alicia Rebuelta | — | (650) 426 8565 | Other | Redwood City · San Mateo County | — | — |
| Allan Gim Construction Co | Allan Kyu Gim | — | (650) 302 4025 | GC, remodel, ADU | South San Francisco · San Mateo County | — | — |
| Allan V Burnett | Allan V Burnett | — | (650) 591 1267 | Windows, patio, painters | Belmont · San Mateo County | — | — |
| Allbay Landscaping INC | Jose Luis Ayala | — | (650) 726 0438 | Windows, patio, painters | Pacifica · San Mateo County | — | — |
| Allen Drywall & Associates | Richard Marvin Allen | — | (650) 579 0664 | Other | Burlingame · San Mateo County | — | — |
| Allen Ho | Allen Ho | — | (650) 255 3688 | GC, remodel, ADU | San Carlos · San Mateo County | — | — |
| Allen Leong | Allen Leong | — | (650) 303 4824 | Electricians | Pacifica · San Mateo County | — | — |
| Allen Mechanical Plumbing Co | Michael Joseph Allen | — | (415) 559 1051 | Other | So San Francisco · San Mateo County | — | — |
| Alliance Demolition INC | Francisco Evandro Vasconcelos | alliancedemolitionca@gmail.com | (650) 931 7775 | Other | San Mateo · San Mateo County | — | — |
| Allied Bay Contractors | Atieh Ahmad Khalaf | alliedbaycontractors@gmail.com | (650) 284 8542 | GC, remodel, ADU | San Bruno · San Mateo County | — | — |
| Allied Builders | Chad Roy Engstrom | — | (650) 714 3295 | GC, remodel, ADU | San Carlos · San Mateo County | — | — |
| Allstar Construction Innovations LLC | Victor Alfonso Perez | — | (650) 776 5607 | GC, remodel, ADU | Redwood City · San Mateo County | — | — |
| Allstar Electric Innovations | Jorge Correa Perez | — | (650) 906 5766 | Electricians | San Mateo · San Mateo County | — | — |
| Allstar Home Services Corp | Jorge Correa Perez | — | (650) 776 5607 | GC, remodel, ADU | Millbrae · San Mateo County | — | — |
| Allwood Construction INC | Robert Matthew Gomez | info@allwood-construction.com | (650) 366 9521 | GC, remodel, ADU | San Carlos · San Mateo County | — | — |
| Almer Corp | Edward Duke Wall | — | (650) 344 3149 | GC, remodel, ADU | San Mateo · San Mateo County | — | — |
| Almo Construction INC | Rezvani Moghaddam Ali Reza | — | (650) 610 9300 | GC, remodel, ADU | San Carlos · San Mateo County | — | — |
| Alonso Electric | Alonso Francisco | — | (650) 574 3445 | Electricians | San Mateo · San Mateo County | — | — |
| Alpha & Omega Builders INC | Juan Francisco Mejia | — | (650) 271 5823 | GC, remodel, ADU | Daly City · San Mateo County | — | — |
| Alpha Electric Co | Victor Manuel Gomez | — | (650) 255 9451 | Electricians | Menlo Park · San Mateo County | — | — |
| Alpha Plus Appliances Heating & Air Conditioning Services | Angel Jesus Sanchez | — | (650) 303 4886 | HVAC | South San Francisco · San Mateo County | — | — |
| Alpha Restoration And Waterproofing | Emile Eissa Kishek | — | (650) 875 7500 | Other roofers | South San Francisco · San Mateo County | — | — |
| Alpine Construction | Daniel Robert Iii Caughey | — | (831) 246 1221 | GC, remodel, ADU | La Honda · San Mateo County | — | — |
| Alren Electrical | Renato Ocampo Mariano | — | (650) 888 5246 | Electricians | Daly City · San Mateo County | — | — |
| Alternative Heating And Air Conditioning Solutions INC | Julie Ann Mikula | — | (650) 322 4328 | HVAC | San Carlos · San Mateo County | — | — |