| 009 Electric Company | Sean Michael Saxton | — | (626) 484 7423 | Electricians | Riverside · Riverside County | — | — |
| 10-4 Plumbing INC | Lopez Juan Davila | — | (951) 692 6355 | Other | Cherry Valley · Riverside County | — | — |
| 1016 Electric | Giovanni De Jesus Rizo Garcia | — | (951) 437 8485 | Electricians | San Jacinto · Riverside County | — | — |
| 111 Painting And Decorating | Haro Samuel Bernal | — | (760) 308 7590 | Windows, patio, painters | Coachella · Riverside County | — | — |
| 1111 Heating And Air Conditioning | Jr Ubaldo Franco | — | (951) 963 6305 | HVAC | Corona · Riverside County | — | — |
| 1111 HVAC Services LLC | Jesse Clayton Anderson | — | (951) 519 3211 | HVAC | Menifee · Riverside County | — | — |
| 1320 Electric | Juan Jose Corona | — | (951) 642 8393 | Electricians | Riverside · Riverside County | — | — |
| 1ichard A Mathews | 1ichard A Mathews | — | (951) 322 6727 | GC, remodel, ADU | Lake Elsinore · Riverside County | — | — |
| 1st Atrium INC | Arne Edgar Perthus | — | (760) 880 6606 | Electricians | Palm Desert · Riverside County | — | — |
| 1st Choice Construction Co | Nathaniel Leroy Duncan | — | (760) 851 8821 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| 1st Choice Electric INC | Jerrett Scott Bruemmer | — | (909) 247 5849 | Electricians | Norco · Riverside County | — | — |
| 1st Concept Construction INC | Sandeep Amratlal Patel | — | (951) 256 6517 | GC, remodel, ADU | Corona · Riverside County | — | — |
| 1st Gen Plumbing LLC | Gustavo Arturo Lizarraga | — | (951) 897 3617 | Other | Perris · Riverside County | — | — |
| 1st Team Air Conditioning INC | Brad Webb Daniels | — | (951) 698 7007 | HVAC | Murrieta · Riverside County | — | — |
| 1V Comunications | Jason Leon Wurtz | — | (626) 400 0449 | Other | Jurupa Valley · Riverside County | — | — |
| 2 2 0 Carpet Installation | 2 2 0 Carpet Installation | — | (951) 565 7149 | Other | Hemet · Riverside County | — | — |
| 2 Down | 2 Down | — | (951) 775 4702 | Other | Murrieta · Riverside County | — | — |
| 2 Kings Builders | Jeffrey Thomas Vonbargen | mail@kings-builders.com | (951) 336 9602 | GC, remodel, ADU | Norco · Riverside County | — | — |
| 2 Ko General Construction | Jose Luis Robles Garcia | kogeneralconstruction@gmail.com | (714) 628 6847 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| 2 Mh Construction | Mehrzad Mosayebi Heravi | — | (951) 551 3434 | GC, remodel, ADU | Temecula · Riverside County | — | — |
| 2 Tone Custom Painting | 2 Tone Custom Painting | — | (951) 634 7492 | Windows, patio, painters | Menifee · Riverside County | — | — |
| 20 / 20 Plumbing & Heating INC | Charles Conaway Iii Cockey | — | (951) 396 2020 | HVAC | Riverside · Riverside County | — | — |
| 20 / 20 Roofing Co INC | Copado Saul | — | (760) 578 7799 | Other roofers | Indio · Riverside County | — | — |
| 20/20 Reglazing & Refinishing | Martinique Danielle Garcia | — | (760) 396 8558 | Other | Desert Hot Springs · Riverside County | — | — |
| 2020 Demolition And Grading INC | Pablo Ortiz | — | (213) 798 9015 | Other | Riverside · Riverside County | — | — |
| 20th Century Air INC | Scott Robert Baker | — | (714) 450 5060 | HVAC | Murrieta · Riverside County | — | — |
| 20th Century Pools-palm Springs INC | Jose Manuel Mendoza | — | (951) 757 2347 | GC, remodel, ADU | Wildomar · Riverside County | — | — |
| 21st Century Network Cabling | 21st Century Network Cabling | — | (310) 918 9840 | Other | Menifee · Riverside County | — | — |
| 23 1/2 Hour Home Services INC | Kelly Michael Russum | — | (760) 327 8718 | HVAC | Palm Springs · Riverside County | — | — |
| 24 - 7 Drilling INC DBA 24 - 7 Water Well Drilling | Donald Wayne Kinloch | — | (951) 581 2783 | Other | Norco · Riverside County | — | — |
| 24 - Hour Express Services INC | Michael Lee Weimann | — | (951) 302 5320 | HVAC | Murrieta · Riverside County | — | — |
| 24 7 Protection INC | Arthur Michael Livermore | — | (760) 200 0155 | Electricians | Thousand Palms · Riverside County | — | — |
| 24 Apartment Complex Services INC | Mohamad| Alzgou L Mohamad Al Zgoul | — | (951) 686 7171 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| 24/7 Comfort Cooling & Heating | 24/7 Comfort Cooling & Heating | — | (909) 262 0267 | HVAC | Jurupa Valley · Riverside County | — | — |
| 24/7 Erosion Control INC | Juan Esparza Ramirez | — | (951) 943 9351 | Other | Perris · Riverside County | — | — |
| 24/7 Expert Builders | Steven Octavio Ramos | — | (951) 496 0965 | GC, remodel, ADU | Lake Elsinore · Riverside County | — | — |
| 24/7 Painting INC | Sergio Samuel Curiel Alvarez | — | (951) 217 4252 | Windows, patio, painters | Perris · Riverside County | — | — |
| 24/7 Water And Fire Restoration LLC | Antonio Tejeda | interested@domainmarket.com | (951) 476 5290 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| 24hr Fire & Water Restoration | 24hr Fire & Water Restoration | — | (951) 756 2943 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| 2E Electric | Martinez Eleuterio | — | (949) 939 0387 | Electricians | Riverside · Riverside County | — | — |