| Ross Goodwin INC | Ross Anthony Goodwin | — | (805) 659 2873 | GC, remodel, ADU | Oxnard · Ventura County | — | — |
| Rossi Construction Services | John Michael Rossi | — | (661) 209 9051 | GC, remodel, ADU | Westlake Village · Ventura County | — | — |
| Rote Brothers Constructors INC | Michael Damien Rote | — | (805) 207 8507 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| Roth Development Group | Craig Davis Roth | — | (310) 283 5227 | GC, remodel, ADU | Westlake Village · Ventura County | — | — |
| Rottweiler Carpentry Cabinet & Millwork | Rottweiler Carpentry Cabinet & Millwork | — | (805) 279 7813 | Other | Newbury Park · Ventura County | — | — |
| Roud Custom Building | Roud Custom Building | — | (805) 340 5082 | GC, remodel, ADU | Fillmore · Ventura County | — | — |
| Route 101 Safety INC | Becerril Antonio | — | (805) 983 4801 | Other | Oxnard · Ventura County | — | — |
| Roxarel Building INC | Santiago Arel Contreras | — | (818) 256 0358 | GC, remodel, ADU | Moorpark · Ventura County | — | — |
| Roy Brothers Drilling INC | Alan Clark Goddard | info@roybrothersdrilling.com | (310) 456 8405 | Other | Camarillo · Ventura County | — | — |
| Roy Eliot Kettler | Roy Eliot Kettler | — | (503) 331 3901 | GC, remodel, ADU | Ventura · Ventura County | — | — |
| Royal El Painting | Royal El Painting | — | (805) 248 1741 | GC, remodel, ADU | Simi Valley · Ventura County | — | — |
| Royal Flooring | Badalian Vahik | — | (805) 203 2200 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |
| Royal Flush Air Conditioning | Royal Flush Air Conditioning | — | (323) 901 0837 | HVAC | Fillmore · Ventura County | — | — |
| Royal Gardens Landscape INC | Edward Brian Delaney | — | (805) 523 3280 | Windows, patio, painters | Moorpark · Ventura County | — | — |
| Royal Glass | Royal Glass | — | (805) 626 0732 | Windows, patio, painters | Oxnard · Ventura County | — | — |
| Royal Groundworx INC | Dean Pacich | — | (805) 795 7948 | Windows, patio, painters | Thousand Oaks · Ventura County | — | — |
| Royal Oak Tree Service INC | Castro Bolanos Martin | — | (805) 624 9897 | Tree | Simi Valley · Ventura County | — | — |
| Rq General Building | Rq General Building | — | (805) 889 5091 | GC, remodel, ADU | Port Hueneme · Ventura County | — | — |
| Rrs Solutions | Rrs Solutions | — | (818) 300 5393 | Other | Simi Valley · Ventura County | — | — |
| Rs Construction | Sergio Armando Rodriguez Gomez | — | (818) 389 1120 | GC, remodel, ADU | Simi Valley · Ventura County | — | — |
| Rs Custom Wood Flooring INC | Rutilio Arturo Sanchez Chinchilla | tu@correo.com | (530) 710 6329 | Other | Simi Valley · Ventura County | — | — |
| Rsb Stoneworks INC | Russell Scott Busse | — | (805) 910 5637 | Other | Camarillo · Ventura County | — | — |
| Ruben Adame | Ruben Adame | — | (619) 452 4305 | Other | Moorpark · Ventura County | — | — |
| Rudolph Construction | Nathan Stewart Rudolph | rudolphcc@msn.com | (805) 320 3448 | GC, remodel, ADU | Ventura · Ventura County | — | — |
| Rudy Landscape | Rudy Landscape | — | (805) 760 2846 | Windows, patio, painters | Camarillo · Ventura County | — | — |
| Ruiz Construction Projects | Hector Fabio Ruiz | hectizavaleysah@hotmail.com | (805) 843 8452 | GC, remodel, ADU | Camarillo · Ventura County | — | — |
| Ruiz Masonry & Concrete | Ruiz Masonry & Concrete | — | (805) 793 5565 | Other | Oxnard · Ventura County | — | — |
| Ruiz Painting | Ruiz Painting | — | (805) 701 1320 | Windows, patio, painters | Ventura · Ventura County | — | — |
| Ruiz Wiring Solutions INC | Isaac Ruiz | — | (805) 815 5961 | Other | Oxnard · Ventura County | — | — |
| Runestrand Wood Floors | Runestrand Wood Floors | — | (805) 405 6233 | Other | Ventura · Ventura County | — | — |
| Rush Constructors INC | Kurt John Rush | — | (805) 484 8649 | GC, remodel, ADU | Camarillo · Ventura County | — | — |
| Russell Construction INC | Craig Stephen Russell | — | (805) 402 8453 | GC, remodel, ADU | Simi Valley · Ventura County | — | — |
| Russell Electric | Delfino Russell | eben@eyebytes.com | (805) 388 6189 | Electricians | Camarillo · Ventura County | — | — |
| Russell Fakhr | Russell Fakhr | — | (310) 666 5229 | Other | Westlake Village · Ventura County | — | — |
| Russell Security Solutions | Russell Security Solutions | — | (805) 660 4597 | Alarm and generators | Simi Valley · Ventura County | — | — |
| Russell Soebbing | Russell Soebbing | — | (805) 302 9500 | Other | Camarillo · Ventura County | — | — |
| Rusty Pipe's Plumbing & Drain Service | Russell Gene Valerio | — | (805) 746 9199 | Other | Ventura · Ventura County | — | — |
| Rvb Enterprises | Valladolid Bravo Rafael | — | (805) 421 9029 | GC, remodel, ADU | Ventura · Ventura County | — | — |
| Rw Communications INC | Ryan Daniel Walker | — | (805) 701 1556 | Other | Oxnard · Ventura County | — | — |
| Rx Builders | William Sakichi Parish | — | (310) 739 6160 | GC, remodel, ADU | Thousand Oaks · Ventura County | — | — |