| Trelane Construction | Matthew Trelane Balhorn | — | (925) 784 3101 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| Tri - City Fire Protection INC | Timothy Alexander Lewis | — | (510) 364 4782 | Other | Fremont · Alameda County | — | — |
| Tri - City Roofing INC | Gregory Wayne Glaeser | — | (510) 797 3901 | Other roofers | Fremont · Alameda County | — | — |
| Tri - Valley Electrical Service INC | Ronald Wayne Mize | — | (800) 449 6244 | Electricians | Livermore · Alameda County | — | — |
| Tri - Valley Engineering | Tyler Christopher Reeves | — | (925) 989 3573 | Other | Castro Valley · Alameda County | — | — |
| Tri Sheet Metal | Tri Sheet Metal | — | (510) 760 3539 | Other | Oakland · Alameda County | — | — |
| Tri Star Communications | Tri Star Communications | — | (510) 537 8420 | Other | San Lorenzo · Alameda County | — | — |
| Tri Valley Construction And Design | Stephen Michael Dickinson | — | (925) 719 1049 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| Tri Valley Excavating Co INC | Michael Anthony Garcia | emily@trivalleyx.com | (925) 331 8878 | GC, remodel, ADU | Sunol · Alameda County | — | — |
| Tri Valley Fenceworks INC | Jerrid Cortie Burton | — | (925) 257 2005 | Other | Livermore · Alameda County | — | — |
| Tri Valley Roofing Corp | Ryan Daniel Piekarczyk | — | (925) 948 1090 | Other roofers | Castro Valley · Alameda County | — | — |
| Tri-city Contractors | Ellen Jean Davis | — | (510) 733 6400 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Tri-valley Design | Tri-valley Design | — | (650) 733 6561 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| Tri-valley Garage Pros | Rami Ragaei Bshaie | sales@trivalleygaragepros.com | (925) 502-2596 | Other | Livermore · Alameda County | — | — |
| Triad Fire Protection Systems INC | Jose Louis Valdez | — | (510) 972 0004 | Other | Livermore · Alameda County | — | — |
| Triangle Construction Tri - Valley INC | Daniel Ben Curtis | — | (510) 827 7033 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| Tribay Construction | Tri Minh Pham | — | (510) 882 5457 | Electricians | Oakland · Alameda County | — | — |
| Trim Chip & Go | Trim Chip & Go | — | (510) 766 6011 | Tree | Hayward · Alameda County | — | — |
| Trimacs Maintenance And Landscape Construction INC | Stephen Barry Mc Auliffe | — | (510) 569 9660 | Windows, patio, painters | Oakland · Alameda County | — | — |
| Trimless Drywall | Trimless Drywall | — | (510) 689 3369 | Other | Hayward · Alameda County | — | — |
| Trinity Construction Servicing | Joe T Nuno | — | (408) 313 3694 | GC, remodel, ADU | Alameda · Alameda County | — | — |
| Trinity Liquid Waste Services | Jack Albert Iv Shane | — | (510) 874 6489 | Other | Pleasanton · Alameda County | — | — |
| Trinity Perfect Construction INC | Ashraf Sergoues Ibr| Abdelmeseh Ashraf Serg Ibrahim Abdelmeseh | — | (925) 660 9245 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| Triple Construction INC | Elaine Dan Lin | — | (361) 534 6666 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Triple J & A Builder's Corporation | Jason Paul Mendoza Roque | — | (510) 458 6066 | GC, remodel, ADU | Union City · Alameda County | — | — |
| Triple S Electric Co | Stephen Scott Slauson | zach@tripleselectric.com | (510) 523 8563 | Electricians | Alameda · Alameda County | — | — |
| Tripp Custom Builders | Tripp Custom Builders | — | (510) 378 4828 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Tripp Custom Builders INC | Byron Z Tripp | — | (510) 378 4828 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Tritek Construction INC | Kristie Lynn Boegler | — | (925) 243 1100 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| Triton Heating & Cooling Group | Christian Henry Bedon Pascual | — | (510) 764 2426 | HVAC | San Leandro · Alameda County | — | — |
| Triton HVAC & Appliance Repair | Vladimir A Kim | — | (855) 202 9264 | HVAC | Castro Valley · Alameda County | — | — |
| Trojan Systems INC | Thomas Alan Martin | sales@trojansystems.com | (925) 245 1510 | Electricians | Livermore · Alameda County | — | — |
| Troy Burleigh | Troy Burleigh | — | (510) 894 3364 | GC, remodel, ADU | Newark · Alameda County | — | — |
| Troy's Custom Window Treatment Installations | Troy's Custom Window Treatment Installations | — | (510) 813 4981 | Other | Hayward · Alameda County | — | — |
| Troyer's Door Control INC | Gary Fielding Troyer | — | (650) 871 4202 | Other | Hayward · Alameda County | — | — |
| Tru Painting | Tru Painting | — | (925) 209 4627 | Windows, patio, painters | Pleasanton · Alameda County | — | — |
| Tru Tech Energy Services INC | Jeffrey L Felker | — | (925) 784 5355 | Electricians | Livermore · Alameda County | — | — |
| True Angle Framing | Orlando Carlos Escobar Mejia | — | (510) 753 3883 | Other | Oakland · Alameda County | — | — |
| True Blue Air | True Blue Air | — | (650) 336 4588 | HVAC | Hayward · Alameda County | — | — |
| True Blue Automation Services | Berk Gurkan | — | (925) 808 7331 | Electricians | Pleasanton · Alameda County | — | — |