| #1 Acoustics | Candice Diane Hanisch | — | (510) 489 2985 | Other | Hayward · Alameda County | — | — |
| 1 N 7 General Construction | Zhong Jinfan | — | (415) 370 9822 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| 1-888-heat-pumps | John Linus Grimsich | — | (888) 432 8786 | HVAC | Berkeley · Alameda County | — | — |
| 10square Construction INC | Patrick Bai Lam | — | (510) 501 1827 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| 123 Garage Door | Ming Fang | — | (510) 604 8640 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| 153 Cornerstone Construction INC | Il-Lae Cho | gwebb@cornerstone-construction.com | (832) 259-2520 | Electricians | Fremont · Alameda County | — | — |
| 1P Electric | Juan Pablo Zamora Garcia | contact@1pelectric.com | (510) 826 6905 | Electricians | Hayward · Alameda County | — | — |
| 1st Class Electric | Javier Percy Alejos | — | (510) 305 8376 | Electricians | San Leandro · Alameda County | — | — |
| 2 H | 2 H | — | (415) 606 0729 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| 20/20 Builders | Joel Norman Meltzer | — | (510) 531 0102 | GC, remodel, ADU | Emeryville · Alameda County | — | — |
| 2050 Innovation Construction | Demetrius Dwayne Esclovon | — | (510) 313 8556 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| 29 Craftsmen Holdings DBA 29 Craftsmen Painting | Sergio Antonio Aldana | — | (510) 371 2301 | Windows, patio, painters | Dublin · Alameda County | — | — |
| 2Y Construction INC | Huh Youl | — | (510) 760 3023 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| 3 D Construction INC | Joseph Elmer Kettle | — | (925) 519 8323 | GC, remodel, ADU | Dublin · Alameda County | — | — |
| 360 Degrees Concrete INC | Alejandre Adrian Rodriguez | impallari@gmail.com | (209) 321 6889 | Other | Fremont · Alameda County | — | — |
| 360 Property Solutions LLC | Clare Catherine Woakes | — | (510) 418 1430 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| 361 Construction INC | Sasa Saratlija | — | (415) 881 8787 | Electricians | Oakland · Alameda County | — | — |
| 3D Remodeling & Construction | Brady Tingyang Yu | — | (510) 207 8694 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| 3D Remodeling INC | James Randall Kens Alexander | sales@3dremodeling.com | (925) 525-0708 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| 3D Signs LLC | Keping Jiang | — | (510) 918 8129 | Other | San Leandro · Alameda County | — | — |
| 3D Studio INC DBA Joseph Farais | Joseph Patrick Farais | — | (510) 220 0220 | Other | Oakland · Alameda County | — | — |
| 3rdgen Home Services DBA 3rdgen Heating And Cooling | Devin Rodolfo Osorio | — | (866) 222 7980 | HVAC | Berkeley · Alameda County | — | — |
| 4 Bay Painting | 4 Bay Painting | — | (510) 710 2442 | Windows, patio, painters | Pleasanton · Alameda County | — | — |
| 4 Craftsmen Construction INC | Michael Stanton Riter | — | (925) 245 8900 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| 4 Real Construction INC | Edward John Tallman | — | (510) 773 4490 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| 4 Season Land Care | 4 Season Land Care | — | (510) 461 5159 | Windows, patio, painters | Newark · Alameda County | — | — |
| 4 Wr Contracting | Horacio R Woolcott | info@wrcontracting.com | (510) 910 1911 | GC, remodel, ADU | Piedmont · Alameda County | — | — |
| 4-seasons Heating & Air Conditioning | Rodriguez Alexander | — | (510) 886 3112 | HVAC | Castro Valley · Alameda County | — | — |
| 4C Construction Systems LLC | Yonah Aharon Naftaly | — | (650) 200 3182 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| 4sigma Home Development | Jawad Yousofi | — | (925) 525 5898 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| 5-year Plan LLC | Jose Estephano Heim | — | (415) 602 4837 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| 510 Painting & Decorating | 510 Painting & Decorating | — | (510) 292 5093 | Windows, patio, painters | Oakland · Alameda County | — | — |
| 7X Construction | Xuan Quang Nguyen | — | (510) 860 6800 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| 808-electric LLC | Ross Belden Flores | — | (510) 565 0216 | Electricians | Fremont · Alameda County | — | — |
| 9 Islands Construction INC | Gil Norberto Boim | interested@domainmarket.com | (510) 935 4858 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| 911 Garage Doors | 911 Garage Doors | — | (510) 292 1644 | Other | Hayward · Alameda County | — | — |
| A & A City Electric INC | Jose Maximiliano Jr Paredes | — | (415) 314 5251 | Electricians | Hayward · Alameda County | — | — |
| A & A Door Repair INC | Armando Guillen-Magana | aadoorrepairinc@gmail.com | (510) 681 5535 | Other | Newark · Alameda County | — | — |
| A & A Remodelers | A & A Remodelers | — | (925) 964 3800 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| A & B Construction | Michael Eugene Stephens | — | (510) 524 5254 | GC, remodel, ADU | Berkeley · Alameda County | — | — |