| Impact Non-electrical Sign & Graphics Of California | Ryan Allan O'coyne | — | (951) 221 5588 | Other | Riverside · Riverside County | — | — |
| Impact Plumbing INC | Nicholas John Collura | — | (951) 987 3285 | GC, remodel, ADU | Moreno Valley · Riverside County | — | — |
| Imperial Building Co | Palafox Martin | — | (909) 519 8867 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Imperial Crown Lath & Plastering | Imperial Crown Lath & Plastering | — | (951) 425 0490 | Other | Riverside · Riverside County | — | — |
| Imperial Flooring Concepts INC | Campos Erica | — | (951) 653 0300 | Other | Moreno Valley · Riverside County | — | — |
| Imperial Grading | Imperial Grading | — | (951) 220 5719 | Other | Moreno Valley · Riverside County | — | — |
| Imperial Outdoors Solutions INC | Marcelo Macias | — | (877) 533 8175 | Windows, patio, painters | Beaumont · Riverside County | — | — |
| Imperial Painters INC | Raul Solis Martinez | — | (760) 353 9566 | Windows, patio, painters | Corona · Riverside County | — | — |
| Imperial Peak Construction | Matthew Alfonse Trejo | amkryukov@gmail.com | (909) 815 2205 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Imperial Roofing & Gutters INC | Ricardo Ortega | service@imperialrainguttersinc.com | (951) 509 9321 | Other roofers | Riverside · Riverside County | — | — |
| Imperios Concrete INC | Ernesto Alejandro Rios Lopez | — | (951) 489 2393 | Other | Perris · Riverside County | — | — |
| Imperium Patio Covers INC | Juan Manuel Nava Vargas | — | (760) 574 6208 | Other | Indio · Riverside County | — | — |
| Imperium Strategies Group INC | Idan Sr Tal | projects@imperiumstrategiesgroup.com | (951) 855-0513 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Impetus Construction INC | Harold Jose Zapata | — | (951) 480 4000 | GC, remodel, ADU | Hemet · Riverside County | — | — |
| Improved Plumbing Corporation | Eduardo Molina | — | (909) 414 7670 | Other | Lake Elsinore · Riverside County | — | — |
| Imr Incorporated | Martinez Ivan | — | (951) 751 0716 | Windows, patio, painters | Norco · Riverside County | — | — |
| In Home Carpet | In Home Carpet | — | (909) 720 0069 | Other | Corona · Riverside County | — | — |
| In Hot Water Plumbing | Steven Perry Reynolds | — | (623) 980 5006 | Other | Temecula · Riverside County | — | — |
| In Line Electric LLC | Jason Robert Bennett | — | (951) 514 5958 | Electricians | Winchester · Riverside County | — | — |
| In Motion Networks Corporation | Megan Leann Chester | — | (951) 894 8809 | Electricians | Murrieta · Riverside County | — | — |
| In-control Audio Video | In-control Audio Video | — | (760) 521 7297 | Other | Cathedral City · Riverside County | — | — |
| In-depth General Engineering LLC | Ryan Christopher Stephenson | — | (909) 838 5986 | Other | Calimesa · Riverside County | — | — |
| Inca Landscape | Inca Landscape | support@incalandscape.com | (909) 229 8084 | Windows, patio, painters | Temecula · Riverside County | — | — |
| Incomm Networks LLC | Alan Omar Marquez-martinez | — | (951) 210 3199 | Other | Perris · Riverside County | — | — |
| Incon Insulation Contractors | Christopher John Glass | — | (951) 313 9347 | Other | Moreno Valley · Riverside County | — | — |
| Incredible Landscape | Incredible Landscape | — | (714) 418 8729 | Windows, patio, painters | Hemet · Riverside County | — | — |
| Independent Construction Company | Shawn Leo Giocomarra | brian@independent-construction.com | (951) 797 9219 | GC, remodel, ADU | Canyon Lake · Riverside County | — | — |
| Independent Electric Company | Tyson Douglas Pollitt | info@independentelectric.com | (951) 727 7777 | Electricians | Wildomar · Riverside County | — | — |
| Independent Electric Contracting INC | Victor Manuel Jr Nino | — | (760) 578 4707 | Electricians | Thermal · Riverside County | — | — |
| Independent General Building Restorers | Independent General Building Restorers | — | (951) 235 6048 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Independent Management Services | Lacatus Daniel | — | (951) 830 1898 | GC, remodel, ADU | Riverside · Riverside County | — | — |
| Independent Masonry Corporation | James Alan Jr Scholl | — | (951) 687 1111 | Other | Riverside · Riverside County | — | — |
| Independent Tile Company | Zachary Ryan Hybbert | — | (951) 265 8422 | Other | Canyon Lake · Riverside County | — | — |
| Indian Wells Glass & Mirror INC | Meredith James Seuss | — | (760) 779 0340 | Windows, patio, painters | Palm Desert · Riverside County | — | — |
| Indio Drywall INC | Jose Manuel Lopez | — | (760) 835 1462 | GC, remodel, ADU | Indio · Riverside County | — | — |
| Indio Hills Pool Construction | Cazarez Cenen | — | (760) 393 6720 | Windows, patio, painters | Desert Hot Springs · Riverside County | — | — |
| Industrial Asphalt Paving | Christopher Joseph Lucas | — | (951) 623 4898 | Other | Perris · Riverside County | — | — |
| Industrial Corrective Maintenance Services | Steven Albert Lopez | — | (951) 202 4795 | Other | Riverside · Riverside County | — | — |
| Industrial Masonry Incorporated | Greg Edmond Wilson | — | (951) 284 3456 | Other | Norco · Riverside County | — | — |
| Industrial Pro Power Services INC | Tika Ram Lama | — | (714) 273 6537 | Electricians | Corona · Riverside County | — | — |