| Lonestar | Michael Charles Drown | — | (951) 672 7946 | Pool | Menifee Valley · Riverside County | — | — |
| Lonestar Plumbing INC | Jesse William Schenck | — | (951) 291 8720 | Other | Lake Elsinore · Riverside County | — | — |
| Long Horn Builders LLC | Daniel Lopez Perez | office@longhornbuilders.com | (760) 702 7661 | GC, remodel, ADU | Cathedral City · Riverside County | — | — |
| Long Horn Concrete Pumping INC | Elvia Estela Angulo | — | (909) 721 8727 | Other | Jurupa Valley · Riverside County | — | — |
| Long Lasting Roof Repair Riverside | Long Lasting Roof Repair Riverside | — | (951) 471-9812 | Other roofers | Riverside · Riverside County | — | — |
| Long Yu | Long Yu | — | (408) 583 7393 | GC, remodel, ADU | Eastvale · Riverside County | — | — |
| Long's Directional Boring INC | Kathleen Margaret Long | — | (951) 817 0111 | Other | Norco · Riverside County | — | — |
| Longhorn Concrete Construction | Luis Rudolfo Sosa | — | (951) 379 8200 | Other | Perris · Riverside County | — | — |
| Longoria Paint & Wall Covering | Longoria Paint & Wall Covering | — | (951) 334 4111 | Windows, patio, painters | Moreno Valley · Riverside County | — | — |
| Loombre Pools LLC | Ceja Francisco Nunez | — | (760) 989 0143 | Pool | Indio · Riverside County | — | — |
| Lopez Concrete Coring | Lopez Concrete Coring | — | (951) 265 5694 | Windows, patio, painters | Hemet · Riverside County | — | — |
| Lopez Construction | Jose Antonio Lopez | — | (951) 373 9946 | Other | Corona · Riverside County | — | — |
| Lopez Construction & Renovations | Juan Manuel Jr Lopez | — | (760) 534 5556 | GC, remodel, ADU | Palm Desert · Riverside County | — | — |
| Lopez Development Company | Lopez Mario | — | (760) 578 1010 | GC, remodel, ADU | Cathedral City · Riverside County | — | — |
| Lopez Garage Door Service | Fernando Evaristo Lopez | — | (714) 417 7556 | Other | Corona · Riverside County | — | — |
| Lopez Gardening Service A Partnership | Carol Sue Bartley | — | (760) 534 0611 | Windows, patio, painters | Cathedral City · Riverside County | — | — |
| Lopez Jr Quality Contractors INC | Jose Rafael Lopez Miguel | info@lopezjrqualitycontractors.com | (951) 538 9618 | GC, remodel, ADU | Moreno Valley · Riverside County | — | — |
| Lopez Mechanical Solutions | Pedro Pablo Lopez Martinez | — | (619) 890 2382 | HVAC | Menifee · Riverside County | — | — |
| Lopez Millwork INC | Oscar Israel Lopez | — | (951) 447 2631 | Other | Perris · Riverside County | — | — |
| Lopez Painting & Wall Covering | Griselda Lopez | — | (626) 324 8157 | Windows, patio, painters | Eastvale · Riverside County | — | — |
| Lopez Patio Covers | Lopez Patio Covers | — | (951) 220 9324 | Other | Riverside · Riverside County | — | — |
| Lopez Tile & Stone | Lopez Tile & Stone | — | (951) 704 9295 | Other | Menifee · Riverside County | — | — |
| Lopez Tree Maintenance INC | Tomas Diego Lopez | — | (951) 536 3116 | Tree | Moreno Valley · Riverside County | — | — |
| Lopez Tree Service INC | Santos Lopez-Colin | — | (760) 329 4174 | Windows, patio, painters | Desert Hot Springs · Riverside County | — | — |
| Lopez Woodworks | Lopez Woodworks | — | (562) 652 5951 | Other | Moreno Valley · Riverside County | — | — |
| Loredo Landscape INC | Daniel Loredo Martinez | — | (951) 623 5359 | Windows, patio, painters | Perris · Riverside County | — | — |
| Loren Brugger's Welding | Loren Brugger's Welding | — | (909) 229 3877 | Other | Riverside · Riverside County | — | — |
| Lorenzo's Painting Services | De La Cruz Concepcion Lorenzo | — | (951) 610 3525 | Windows, patio, painters | Perris · Riverside County | — | — |
| Lorry D Hales | Lorry D Hales | — | (951) 600 1742 | GC, remodel, ADU | Murrieta · Riverside County | — | — |
| Lorsung Brothers INC | Jeremy Joseph Lorsung | — | (949) 394 3827 | Other | Riverside · Riverside County | — | — |
| Los Coyotes Plumbing INC | John Wesley Trauger | — | (951) 640 7604 | Other | Nuevo · Riverside County | — | — |
| Los Makitas Builders | Luis Roberto Quinonezceren | — | (951) 376 1040 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Los Toritos Pool Excavation INC | Romo Heli Gutierrez | — | (760) 275 2290 | Pool | Indio · Riverside County | — | — |
| Los Toros Construction INC | Adam Nathaniel Velez | — | (442) 268 5029 | GC, remodel, ADU | Cathedral City · Riverside County | — | — |
| Losacco Electric INC | Marc Anthony Losacco | — | (760) 533 8359 | Electricians | Temecula · Riverside County | — | — |
| Lost Art Granite & Marble INC | Christopher Warren Redman | — | (951) 652 1747 | Other | Hemet · Riverside County | — | — |
| Lotshaw Service | Charles William Lotshaw | — | (951) 769 3970 | HVAC | Cherry Valley · Riverside County | — | — |
| Lotus Pool Maintenance | David James Dobson | — | (760) 902 2142 | Pool | Calimesa · Riverside County | — | — |
| Lou's Heating And Air Conditioning INC | Luis Benavides Ortiz | — | (951) 928 6270 | HVAC | Nuevo · Riverside County | — | — |
| Louch Company INC | Timothy James Louch | — | (949) 324 8637 | GC, remodel, ADU | Lake Elsinore · Riverside County | — | — |