| Raleigh Mechanical & Metals Turning, Bending, Welding | Raleigh, NC | TurningBendingWelding | - |
| Ram Tool Inc Milling, Turning, Welding, Casting, EDM, Grinding · ISO 9001, ITAR | Grafton, WI | MillingTurningWeldingCastingEDMGrinding | ISO 9001, ITAR |
| Ramp Engineering Inc Milling, Turning, Swiss | Paramount, CA | MillingTurningSwiss | - |
| Rand Machine Works Milling, Turning, Bending, Welding | Fresno, CA | MillingTurningBendingWelding | - |
| Range Precision Milling, Turning, EDM, Grinding, Finishing | Blaine, MN | MillingTurningEDMGrindingFinishing | - |
| Rapid Precision Works LLC Milling, Turning, EDM | Alachua, FL | MillingTurningEDM | - |
| Rapid Prototyping & Engineering, Inc Milling, Turning, Waterjet, Welding, EDM, Assembly | Franklin, IN | MillingTurningWaterjetWeldingEDMAssembly | - |
| Ray Machine Inc Milling, Turning, Laser, Bending, Welding, Finishing · ISO 9001, AS9100 | Middle River, MD | MillingTurningLaserBendingWeldingFinishing | ISO 9001, AS9100 |
| RBH Aerospace Inc Milling, Turning, Waterjet, Bending | Lakewood, CA | MillingTurningWaterjetBending | - |
| RDL Machine, LLC Milling, Turning, Waterjet, Welding, Stamping, EDM, Grinding · ISO 9001, AS9100 | Bossier City, LA | MillingTurningWaterjetWeldingStampingEDMGrinding | ISO 9001, AS9100 |
| RDS Machine, LLC Milling, Turning, Finishing · ISO 9001, AS9100, ITAR, NADCAP | Newport, NH | MillingTurningFinishing | ISO 9001, AS9100, ITAR, NADCAP |
| Redbell Manufacturing LLC Milling, Turning, Finishing, Assembly | Logan, UT | MillingTurningFinishingAssembly | - |
| Regal Research & Manufacturing Co LLC Milling, Turning, Bending, Welding, Grinding, Finishing, Assembly · ISO 9001, AS9100, ITAR | Plano, TX | MillingTurningBendingWeldingGrindingFinishingAssembly | ISO 9001, AS9100, ITAR |
| Reisinger Automation & Design LLC Milling, Turning, Waterjet, Welding, Grinding, Finishing | Reading, PA | MillingTurningWaterjetWeldingGrindingFinishing | - |
| Rensberger Technologies Milling, Turning, EDM · AS9100, ITAR, CMMC | Sioux Falls, SD | MillingTurningEDM | AS9100, ITAR, CMMC |
| Resivine LLC Milling, Turning, Waterjet, EDM, Grinding | Houston, TX | MillingTurningWaterjetEDMGrinding | - |
| Responsive Machining Inc Milling, Turning · ISO 9001, AS9100 | Titusville, FL | MillingTurning | ISO 9001, AS9100 |
| Reuss Industries, Inc Milling, Turning, Waterjet, Welding, EDM, Grinding | Madison, PA | MillingTurningWaterjetWeldingEDMGrinding | - |
| RGS Machine Inc Milling, Turning, Swiss · ISO 9001 | Folsom, PA | MillingTurningSwiss | ISO 9001 |
| RHS Precision LLC Milling, Turning, Finishing · ITAR | Edgewood, MD | MillingTurningFinishing | ITAR |
| Ricaurte Precision Inc Milling, Turning, Swiss, Laser, EDM, Finishing, Assembly · ISO 9001, ITAR | Santa Ana, CA | MillingTurningSwissLaserEDMFinishingAssembly | ISO 9001, ITAR |
| Rice Precision Manufacturing Inc Milling, Turning, Swiss, Laser, Waterjet, Welding, Finishing, Assembly · ISO 9001, AS9100 | Baldwin City, KS | MillingTurningSwissLaserWaterjetWeldingFinishingAssembly | ISO 9001, AS9100 |
| Richards Design, Inc Milling, Turning, Welding, EDM, Assembly · ISO 9001 | East Falmouth, MA | MillingTurningWeldingEDMAssembly | ISO 9001 |
| Richards Sheet Metal Turning, Bending, Laser, Welding, Stamping · ISO 9001 | Ogden, UT | TurningBendingLaserWeldingStamping | ISO 9001 |
| Rigid Concepts LLC Milling, Turning, Finishing · ISO 9001, ITAR | Van Alstyne, TX | MillingTurningFinishing | ISO 9001, ITAR |
| Rincon Engineering Corporation Milling, Turning, Laser, Waterjet, Punching, Welding, Stamping, EDM, Finishing · ISO 9001, AS9100 | Carpinteria, CA | MillingTurningLaserWaterjetPunchingWeldingStampingEDMFinishing | ISO 9001, AS9100 |
| Ring Precision Milling, Turning, Swiss, Welding, EDM, Grinding | Jamestown, NY | MillingTurningSwissWeldingEDMGrinding | - |
| RivCut Milling, Turning, Bending, Metal AM · ISO 9001, AS9100, ITAR | Union City, CA | MillingTurningBendingMetal AM | ISO 9001, AS9100, ITAR |
| Riverside Machine & Automation Inc Milling, Turning, Welding, Stamping, Grinding, Assembly | Genoa, OH | MillingTurningWeldingStampingGrindingAssembly | - |
| RJ Enterprises Milling, Turning, EDM · ISO 9001, AS9100, ITAR | Gardena, CA | MillingTurningEDM | ISO 9001, AS9100, ITAR |
| RJC Manufacturing Services LLC Milling, Turning, Bending, Welding | Irwin, PA | MillingTurningBendingWelding | - |
| Roaring Creek Machine Co Milling, Turning, Laser, Bending, Welding, Finishing · ITAR | Catawissa, PA | MillingTurningLaserBendingWeldingFinishing | ITAR |
| Rogue Precision Manufacturing LLC Milling, Turning | Tomball, TX | MillingTurning | - |
| Ross Manufacturing, Inc Milling, Turning, Laser, Bending, Welding, Finishing | Saint Francis, KS | MillingTurningLaserBendingWeldingFinishing | - |
| Rota Industries Milling, Turning, EDM, Grinding, Assembly | Farmingdale, NY | MillingTurningEDMGrindingAssembly | - |
| Roush & Yates Racing Engines LLC Milling, Turning, Swiss, Waterjet, Finishing · AS9100, ITAR, NADCAP, ISO 13485 | Mooresville, NC | MillingTurningSwissWaterjetFinishing | AS9100, ITAR, NADCAP, ISO 13485 |
| Roysters Machine Shop LLC Milling, Turning, Waterjet, Welding, Stamping, EDM · ISO 9001 | Henderson, KY | MillingTurningWaterjetWeldingStampingEDM | ISO 9001 |
| Rozic Tool & Machine LLC Milling, Turning, EDM · ISO 9001 | Euclid, OH | MillingTurningEDM | ISO 9001 |
| RS Precision Milling, Turning, Swiss, EDM, Grinding · ISO 9001, AS9100, ITAR, CMMC | Farmingdale, NY | MillingTurningSwissEDMGrinding | ISO 9001, AS9100, ITAR, CMMC |
| Russard Inc Milling, Turning · ISO 9001 | Rockland, MA | MillingTurning | ISO 9001 |
| Ryan Manufacturing Inc Milling, Turning · ISO 9001, AS9100 | Haskell, OK | MillingTurning | ISO 9001, AS9100 |
| S & R Tool, Inc Milling, Turning, Welding, EDM · AS9100 | Lakeville, NY | MillingTurningWeldingEDM | AS9100 |
| S & S Commercial Fishing Equipment, Incorporated Milling, Turning, Welding | Roseville, CA | MillingTurningWelding | - |
| S & S Machine Inc Milling, Turning, Waterjet, Punching, Bending, Welding, Assembly · ISO 9001, AS9100, ITAR | Irving, TX | MillingTurningWaterjetPunchingBendingWeldingAssembly | ISO 9001, AS9100, ITAR |
| S R Machining, Inc Milling, Turning, Swiss, Welding, Casting · ISO 9001, AS9100 | Norco, CA | MillingTurningSwissWeldingCasting | ISO 9001, AS9100 |
| S&W Precision Machining LLC Milling, Turning · ISO 9001, AS9100, ITAR, CMMC | Commerce City, CO | MillingTurning | ISO 9001, AS9100, ITAR, CMMC |
| Saar Corp Milling, Turning, Swiss, Finishing, Assembly · AS9100 | Farmington, CT | MillingTurningSwissFinishingAssembly | AS9100 |
| Sabrin Turning, Welding, EDM, Assembly · AS9100 | Pasadena, CA | TurningWeldingEDMAssembly | AS9100 |
| Salco Inc Milling, Turning, Swiss, Welding, Assembly · ISO 9001 | Arvada, CO | MillingTurningSwissWeldingAssembly | ISO 9001 |
| Saliba Industries Milling, Turning, Grinding | Waukegan, IL | MillingTurningGrinding | - |