| Roger Renslow Construction | Roger Leroy Renslow | — | (209) 470 1264 | GC, remodel, ADU | Oakdale · Stanislaus County | — | — |
| Roman Acts Electrical & Lighting | Craig Curtis Faulder | — | (209) 499 0486 | Electricians | Modesto · Stanislaus County | — | — |
| Romero & Sons Construction INC | Manuel Romero Palma | — | (209) 456 0131 | GC, remodel, ADU | Oakdale · Stanislaus County | — | — |
| Romero Concrete Coring | Romero Concrete Coring | — | (209) 617 2818 | Other | Newman · Stanislaus County | — | — |
| Romo's Pools | Maria Guadalupe Romo | romospools1@gmail.com | (209) 204 8676 | Pool | Modesto · Stanislaus County | — | — |
| Ron's Gutters | Ron's Gutters | — | (209) 604 3869 | Other | Oakdale · Stanislaus County | — | — |
| Ronald Stephen Genasci | Ronald Stephen Genasci | — | (209) 483 2773 | Other | Riverbank · Stanislaus County | — | — |
| Roofing Pro Construction INC | Guzman Geronimo Mercado | — | (559) 389 8597 | Other roofers | Patterson · Stanislaus County | — | — |
| Rosales Heating And Air Conditioning | Rosales Heating And Air Conditioning | — | (415) 716 1243 | HVAC | Oakdale · Stanislaus County | — | — |
| Rose Construction Services | Sergio Alejandro Esparza Magana | — | (209) 214 2791 | GC, remodel, ADU | Modesto · Stanislaus County | — | — |
| Rose Construction Services INC | Sergio Alejandro Esparza Magana | — | (209) 214 2791 | GC, remodel, ADU | Modesto · Stanislaus County | — | — |
| Rose Heating - Air Conditioning & Sheet Metal | Keith Joseph Udovch | — | (209) 577 5745 | HVAC | Modesto · Stanislaus County | — | — |
| Ross Anderson General Contractor | Ross Anderson General Contractor | — | (209) 485 0839 | GC, remodel, ADU | Turlock · Stanislaus County | — | — |
| Ross F Carroll INC | Sheila Marren Carroll | — | (209) 848 5959 | GC, remodel, ADU | Oakdale · Stanislaus County | — | — |
| Ross Jackson General Contractor | Ross Jackson General Contractor | — | (650) 207 8773 | GC, remodel, ADU | Modesto · Stanislaus County | — | — |
| Roto-rooter | Rodney Allen Wray | — | (925) 532 3995 | Other | Oakdale · Stanislaus County | — | — |
| Roy Wells | Roy Wells | — | (209) 985 1380 | HVAC | Ceres · Stanislaus County | — | — |
| Royal Tile & Stone | Donovan Joseph Nimmo | — | (916) 741 9700 | Other | Modesto · Stanislaus County | — | — |
| Royalty Cleaning Services | Mark Wayne Sanny | — | (209) 529 3110 | GC, remodel, ADU | Modesto · Stanislaus County | — | — |
| Rpi Electric INC | David Antonio Rodrigues | — | (209) 268 6047 | Electricians | Hughson · Stanislaus County | — | — |
| Rrj Electric | Mok Roy | — | (408) 417 7771 | Electricians | Modesto · Stanislaus County | — | — |
| Rs Mechanical Heating & Air INC | Ruben Gonzalez Sanchez | — | (209) 605 5623 | HVAC | Modesto · Stanislaus County | — | — |
| Rs Milestone General Engineering INC | Ricardo Ochoa Sanchez | — | (408) 348 0309 | Other | Patterson · Stanislaus County | — | — |
| Rubicon Equity Group INC | Ridge Sutter | — | (209) 484 5935 | GC, remodel, ADU | Modesto · Stanislaus County | — | — |
| Rubik Built LLC | Tommy Gene Phelen | — | (209) 408 0626 | GC, remodel, ADU | Modesto · Stanislaus County | — | — |
| Rubio Floors | Rubio Floors | — | (209) 663 0894 | Other | Salida · Stanislaus County | — | — |
| Rudy's Blue Collar Tile INC | Rudy Olvera | — | (209) 648 8162 | Other | Turlock · Stanislaus County | — | — |
| Rugged Cross Construction | Stephen Michel Barney | — | (209) 496 7044 | GC, remodel, ADU | Ceres · Stanislaus County | — | — |
| Rui Esteves | Rui Esteves | — | (209) 595 7467 | GC, remodel, ADU | Denair · Stanislaus County | — | — |
| Ruiz Xeriscape | Ruiz Xeriscape | — | (209) 470 5102 | Windows, patio, painters | Modesto · Stanislaus County | — | — |
| Rumble Fabrication INC | Daniel Hubert Rumble | marcus@rumblefabrication.com | (209) 545 1848 | Other | Modesto · Stanislaus County | — | — |
| Rumble Tree INC | Charles John Rumble | — | (209) 544 2212 | Tree | Modesto · Stanislaus County | — | — |
| Russell Haupt Construction And Renovation | Russell Bruce Haupt | — | (209) 201 5550 | GC, remodel, ADU | Ceres · Stanislaus County | — | — |
| Rwj Construction | Randall Wayne Johnson | — | (209) 595 9149 | GC, remodel, ADU | Modesto · Stanislaus County | — | — |
| Ryl Plumbing Corp | David Obet Rojas Banos | — | (209) 489 1409 | Other | Turlock · Stanislaus County | — | — |
| S & E Construction | Steve Allen Perkins | — | (209) 606 7494 | GC, remodel, ADU | Modesto · Stanislaus County | — | — |
| S & R Plumbing | S & R Plumbing | — | (209) 602 7231 | Other | Modesto · Stanislaus County | — | — |
| S A C INC | David Ruvalcaba | — | (209) 542 7018 | Other | Hughson · Stanislaus County | — | — |
| S C Construction | Jacqulyn Nicole Conway | office@scconstruction.biz | (209) 324 5062 | GC, remodel, ADU | Modesto · Stanislaus County | — | — |
| S C S Sierra Construction Services | Nickolaus Miles Redenbaugh | — | (209) 595 0767 | GC, remodel, ADU | Oakdale · Stanislaus County | — | — |