| Lucky Dog Construction INC | Steven Kenneth Medeiros | contact@luckydogconstruction.com | (510) 514 2535 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Lucky Star Landscaping INC | Sanh D Ho | — | (510) 715 6275 | Windows, patio, painters | San Lorenzo · Alameda County | — | — |
| Lucky's Remodeling Services | Luis Humberto Jr Cardenas Morfin | — | (510) 570 6789 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Lucrum Builders INC | James Matthew Shedd | jim@lucrumbuilders.com | (510) 227 0373 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Ludwig Betchart | Anthony Joseph Betchart | — | (510) 673 5022 | Other | Fremont · Alameda County | — | — |
| Ludwig Betchart INC | Waldtraut Emmel Betchart | — | (510) 673 5022 | Other | Fremont · Alameda County | — | — |
| Luis W Yan | Luis W Yan | — | (415) 279 0263 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Lujano Builders INC | Steve Lujano | — | (925) 315 1285 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Luke Taylor Painting | Luke Taylor Painting | — | (925) 980 4619 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| Luke's Custom Pool And Spa Service | Lukas Faeron Swift | — | (925) 548 1034 | Pool | Livermore · Alameda County | — | — |
| Lumibuild INC | Michael John Ponticello | hello@lumibuild.com | (510) 394 0302 | Other | Emeryville · Alameda County | — | — |
| Luminwood Construction INC | Honglian Yang | — | (510) 377 2973 | GC, remodel, ADU | Union City · Alameda County | — | — |
| Lunar Air Systems | Lunar Air Systems | clients@lunarairsystems.com | (408) 502 4201 | HVAC | Union City · Alameda County | — | — |
| Lundy Solar And Roofing Company | Wyndon Rosales Trinidad | — | (408) 459 2273 | Other roofers | Dublin · Alameda County | — | — |
| Lung - Seng Shih DBA A D C M | A D C M | — | (408) 655 8712 | GC, remodel, ADU | Union City · Alameda County | — | — |
| Lupian Plumbing | Lupian Plumbing | — | (510) 919 7425 | Other | San Leandro · Alameda County | — | — |
| Lutz Construction Services INC | Thomas Darren Lutz | — | (925) 570 3347 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| Luu Construction | Hue Lap Luu | — | (510) 299 2470 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Lux Living Construction | Dotter Olga | — | (415) 519 2163 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Lux Tile Corp | Mendoza Valentin Lugo | — | (415) 716 1571 | Other | Hayward · Alameda County | — | — |
| Luxon Electric LLC | Ming Kun Xu | — | (650) 285 0138 | Electricians | Hayward · Alameda County | — | — |
| Luxurious Stone Slabs | Gonzalez Alvaro Carballo | — | (510) 706 2319 | Other | Hayward · Alameda County | — | — |
| Luxury Tile | Luxury Tile | — | (510) 461 0277 | Other | Hayward · Alameda County | — | — |
| Luxviva Studio INC | Yao Hai Qin | info@luxvivastudio.com | (510) 508 2811 | Other | Hayward · Alameda County | — | — |
| Lvia Tile | Lvia Tile | — | (510) 634 2035 | Other | Hayward · Alameda County | — | — |
| Lw Consolidated INC | Szu-Tsung Wang | — | (510) 403 1689 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Lyn Alhorn Design Build LLC | Lyn Marie-Anne Alhorn | — | (510) 914 6240 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Lyons Construction | Kenneth Stephen Lyons | — | (510) 909 2565 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| M & A Painting INC | Marco Antonio Barragan | — | (510) 924 7561 | Windows, patio, painters | Oakland · Alameda County | — | — |
| M & C Construction | Anthony Robert Ades | — | (510) 816 0276 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| M & D Landscaping | Barragan Lorena Pereda | — | (650) 468 7517 | Windows, patio, painters | Hayward · Alameda County | — | — |
| M & M Foundation & Drilling INC | Gregory Charles Moeller | — | (510) 444 2034 | Other | Pleasanton · Alameda County | — | — |
| M 7.24 Builders INC | Gelacio Enrique Cid Barquin | hr@mbuilders.com | (510) 427 9739 | Electricians | Oakland · Alameda County | — | — |
| M A C Refrigeration | M A C Refrigeration | — | (510) 673 6741 | HVAC | Fremont · Alameda County | — | — |
| M A Gunst Design Build LLC DBA Betelgeuse Design/build | Martin Alexander Gunst | — | (510) 332 5958 | GC, remodel, ADU | Emeryville · Alameda County | — | — |
| M A S Metals | Mibzon Roberto Aldana | — | (510) 259 1426 | Other | Union City · Alameda County | — | — |
| M A Services General Contracting | Michael Angelo Kolokithas | — | (650) 208 0549 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| M And G Factory INC DBA Best Marble | Sarah Monique Mcintyre | — | (510) 614 0155 | Other | San Leandro · Alameda County | — | — |
| M B Construction | Benjamin Enrique Macias | — | (510) 760 2553 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| M B Development | M B Development | — | (510) 918 8419 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |