| #1 Acoustics | Candice Diane Hanisch | — | (510) 489 2985 | Other | Hayward · Alameda County | — | — |
| #1 Central Coast Landscape INC | Miguel Angel Solis Vargas | — | (805) 717 0739 | Windows, patio, painters | Nipomo · San Luis Obispo County | — | — |
| #1 Door Stop INC | Freitas Susana De | — | (209) 647 2853 | Other | Manteca · San Joaquin County | — | — |
| #1 Honest Plumber INC | Edward Elesyado Hinojosa | — | (650) 422 4736 | Other | Sunnyvale · Santa Clara County | — | — |
| #1 Pacific Coast Roofing | Francisco Javier Valencia | — | (805) 796 4427 | Other roofers | Oxnard · Ventura County | — | — |
| #1 Pro Elec Jmg INC | Junghoon Song | — | (408) 712 6690 | Electricians | San Jose · Santa Clara County | — | — |
| #1 Quality Painting INC | Pedro Abraham Martinez | — | (415) 577 7599 | Windows, patio, painters | Richmond · Contra Costa County | — | — |
| #1 Son Plumbing INC | James Lincoln Stanfield | — | (909) 904 3774 | Other | Highland · San Bernardino County | — | — |
| 'a' Plumbing And Heating | Michael Robert Niez | — | (909) 585 5203 | HVAC | Big Bear City · San Bernardino County | — | — |
| 'final Touch' Painting | 'final Touch' Painting | — | (415) 601 1017 | Windows, patio, painters | San Mateo · San Mateo County | — | — |
| 'go' Electric | Enrique Jesus Ortiz | — | (323) 222 2370 | Electricians | Los Angeles · Los Angeles County | — | — |
| 'top'pers Painting & Decorating | 'top'pers Painting & Decorating | — | (831) 601 6767 | Windows, patio, painters | Seaside · Monterey County | — | — |
| +nvioronics INC DBA W B Schulte Construction | Christopher Solon Garrett | — | (818) 266 8440 | GC, remodel, ADU | Los Angeles · Los Angeles County | — | — |
| 009 Electric Company | Sean Michael Saxton | — | (626) 484 7423 | Electricians | Riverside · Riverside County | — | — |
| 0303 Construction INC | Juan Manuel Ortega | — | (650) 452 2720 | GC, remodel, ADU | Pacifica · San Mateo County | — | — |
| 04pan Nogada | 04pan Nogada | — | (310) 494 1636 | GC, remodel, ADU | Pasadena · Los Angeles County | — | — |
| 08 Landscaping INC | Juan Ruben Jr Consepcion | — | (760) 782 2190 | Windows, patio, painters | Hesperia · San Bernardino County | — | — |
| 1 - 2 - 3 Plumbing & Rooter | Eduardo Ramirez Alvarado | — | (818) 335 4935 | Other | Sherman Oaks · Los Angeles County | — | — |
| 1 - 877 Quikdry INC | Roger Arnold Christensen | — | (916) 985 8973 | Other | Folsom · Sacramento County | — | — |
| 1 - 888 - 4 - Abatement INC | Neil Dalton Ostrander | — | (916) 231 0090 | GC, remodel, ADU | Rancho Cordova · Sacramento County | — | — |
| 1 - Adam - 12 Garage Door Service | Adam Scott Hudson | — | (916) 955 1410 | Other | Elk Grove · Sacramento County | — | — |
| 1 - Step Up Electric | Verdugo Eduardo | — | (909) 725 1777 | Electricians | Redlands · San Bernardino County | — | — |
| 1 800 Pro-fence | 1 800 Pro-fence | — | (626) 221 9245 | Other | Monrovia · Los Angeles County | — | — |
| 1 A Construction | Kalenyuk Vadim | — | (530) 503 7804 | GC, remodel, ADU | Rancho Cordova · Sacramento County | — | — |
| 1 Above Technology LLC | Yehuda Eliezer Netkin | — | (323) 325 6373 | Other | Los Angeles · Los Angeles County | — | — |
| 1 AC Guys | Sahak Danielyan | — | (213) 444 4223 | HVAC | Panorama City · Los Angeles County | — | — |
| 1 Aircare HVAC | Hrek Oleksandr | — | (209) 281 5663 | HVAC | Oakdale · Stanislaus County | — | — |
| 1 And 1 Electric INC | Khosravi Sami | — | (818) 401 3734 | Electricians | Canoga Park · Los Angeles County | — | — |
| 1 Call Flood & Construction Specialist LLC | Shawn Bush | — | (619) 954 5162 | GC, remodel, ADU | El Cajon · San Diego County | — | — |
| 1 Click Electric | Cody Allyn Phillips | gerencia_comercial@click-electric.com | (760) 504 9282 | Electricians | San Marcos · San Diego County | — | — |
| 1 Day Aluminum Gutters | 1 Day Aluminum Gutters | — | (858) 472 6279 | Other | Poway · San Diego County | — | — |
| 1 Day Coatings Ie | 1 Day Coatings Ie | — | (909) 521 2171 | Other | Orange · Orange County | — | — |
| 1 Day Epoxy Flooring | Jay Franklin Goetz | — | (714) 322 3156 | Other | Anaheim · Orange County | — | — |
| 1 Day Kitchen Bath & Tile Construction Corporation | Pejman Tanaeim | — | (310) 370 0282 | GC, remodel, ADU | Lawndale · Los Angeles County | — | — |
| 1 Day Rooter & Plumbing INC | Varuzhan Josh Balyan | — | (626) 696 9757 | Other | Hacienda Heights · Los Angeles County | — | — |
| 1 Demolition | 1 Demolition | — | (510) 229 6797 | Other | El Cerrito · Contra Costa County | — | — |
| 1 Design Construction Corp | Min Kyung Ho | — | (213) 384 0011 | GC, remodel, ADU | Los Angeles · Los Angeles County | — | — |
| 1 Dream Home Renovations | Ibarra Rafael Trujillo | dreamhomerenovations@myyahoo.com | (865) 661-1531 | GC, remodel, ADU | San Bernardino · San Bernardino County | — | — |
| 1 Earth Landscape & Construction | Robert Pena Cruz | — | (408) 218 5752 | Windows, patio, painters | San Jose · Santa Clara County | — | — |
| 1 Electrical Services | Andrew Boyd Davis | — | (858) 914 1211 | Electricians | San Diego · San Diego County | — | — |