| Radical Fabrications LLC Milling, Turning, Welding, Grinding | Lancaster, CA | MillingTurningWeldingGrinding | - |
| Ram Aerospace Inc Milling, Turning, Laser, Waterjet, EDM, Grinding, Assembly · AS9100, ITAR | Brea, CA | MillingTurningLaserWaterjetEDMGrindingAssembly | AS9100, ITAR |
| Ram Tool Inc Milling, Turning, Welding, Casting, EDM, Grinding · ISO 9001, ITAR | Grafton, WI | MillingTurningWeldingCastingEDMGrinding | ISO 9001, ITAR |
| Range Precision Milling, Turning, EDM, Grinding, Finishing | Blaine, MN | MillingTurningEDMGrindingFinishing | - |
| Raptor Manufacturing LC Milling, Turning, Welding, Grinding · ISO 9001, AS9100, ITAR | Wichita, KS | MillingTurningWeldingGrinding | ISO 9001, AS9100, ITAR |
| RB Industrial Manufacturer LLC Milling, Swiss, Grinding | Racine, WI | MillingSwissGrinding | - |
| RB Machining, Inc Milling, Turning, Grinding · AS9100 | Palmdale, CA | MillingTurningGrinding | AS9100 |
| RDL Machine, LLC Milling, Turning, Waterjet, Welding, Stamping, EDM, Grinding · ISO 9001, AS9100 | Bossier City, LA | MillingTurningWaterjetWeldingStampingEDMGrinding | ISO 9001, AS9100 |
| Reardon Machine Co Inc Milling, Turning, Welding, Stamping, EDM, Grinding | Saint Joseph, MO | MillingTurningWeldingStampingEDMGrinding | - |
| Red Lion Inc Laser, Grinding · AS9100 | Broomfield, CO | LaserGrinding | AS9100 |
| 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 | - |
| Reliance Machining Inc Milling, Turning, Welding, Grinding | Minneapolis, MN | MillingTurningWeldingGrinding | - |
| Resivine LLC Milling, Turning, Waterjet, EDM, Grinding | Houston, TX | MillingTurningWaterjetEDMGrinding | - |
| Reuss Industries, Inc Milling, Turning, Waterjet, Welding, EDM, Grinding | Madison, PA | MillingTurningWaterjetWeldingEDMGrinding | - |
| Revolution Precision Machining LLC Swiss, Grinding, Finishing · ISO 9001, AS9100 | Tulsa, OK | SwissGrindingFinishing | ISO 9001, AS9100 |
| Reynolda Manufacturing Solutions, Inc Milling, Welding, EDM, Grinding · ISO 9001 | East Bend, NC | MillingWeldingEDMGrinding | ISO 9001 |
| Rig Machine Works LLC Milling, Turning, Bending, Welding, Grinding | Stevensville, MT | MillingTurningBendingWeldingGrinding | - |
| Riley Gear Grinding | Saint Augustine, FL | Grinding | - |
| Rima Manufacturing Co Grinding · IATF 16949 | Hudson, MI | Grinding | IATF 16949 |
| Ring Precision Milling, Turning, Swiss, Welding, EDM, Grinding | Jamestown, NY | MillingTurningSwissWeldingEDMGrinding | - |
| Riverside Machine & Automation Inc Milling, Turning, Welding, Stamping, Grinding, Assembly | Genoa, OH | MillingTurningWeldingStampingGrindingAssembly | - |
| RMT Corporation Milling, Turning, Welding, Grinding | Dayton, OH | MillingTurningWeldingGrinding | - |
| Rock Valley Tool, LLC Milling, Turning, Grinding · ISO 9001, AS9100, ITAR | Easthampton, MA | MillingTurningGrinding | ISO 9001, AS9100, ITAR |
| Rocktech Milling, Grinding | Chesterfield, MI | MillingGrinding | - |
| Rota Industries Milling, Turning, EDM, Grinding, Assembly | Farmingdale, NY | MillingTurningEDMGrindingAssembly | - |
| Royal Coatings Grinding, Finishing | Simi Valley, CA | GrindingFinishing | - |
| RS Precision Milling, Turning, Swiss, EDM, Grinding · ISO 9001, AS9100, ITAR, CMMC | Farmingdale, NY | MillingTurningSwissEDMGrinding | ISO 9001, AS9100, ITAR, CMMC |
| Ruhl Inc Milling, Turning, Waterjet, Welding, Grinding | Spring Lake, NC | MillingTurningWaterjetWeldingGrinding | - |
| RW Screw, LLC Grinding | Massillon, OH | Grinding | - |
| S & S Die Co Milling, Turning, Welding, EDM, Grinding | Lansing, MI | MillingTurningWeldingEDMGrinding | - |
| S & S Tool & Machine Co Milling, Turning, Welding, EDM, Grinding · ISO 9001, AS9100, ITAR | Louisville, KY | MillingTurningWeldingEDMGrinding | ISO 9001, AS9100, ITAR |
| Safarik Tool Co Inc Milling, Turning, Grinding · ISO 9001 | Valley Center, KS | MillingTurningGrinding | ISO 9001 |
| Saliba Industries Milling, Turning, Grinding | Waukegan, IL | MillingTurningGrinding | - |
| Sanks Machining Inc Milling, Turning, Waterjet, Welding, EDM, Grinding | Staunton, IL | MillingTurningWaterjetWeldingEDMGrinding | - |
| Santa Lucia Manufacturing, Inc Milling, Turning, Grinding | Atascadero, CA | MillingTurningGrinding | - |
| Schaefer Screw Products Co Milling, Turning, Grinding, Finishing | Garden City, MI | MillingTurningGrindingFinishing | - |
| Schmid Tool & Engineering Corp Milling, Turning, Swiss, Stamping, Grinding, Finishing, Assembly · ISO 9001, ITAR | Villa Park, IL | MillingTurningSwissStampingGrindingFinishingAssembly | ISO 9001, ITAR |
| Schmiede Corporation Milling, Turning, Welding, EDM, Grinding, Assembly · ISO 9001 | Tullahoma, TN | MillingTurningWeldingEDMGrindingAssembly | ISO 9001 |
| Schneiders Manufacturing Inc Milling, Turning, Swiss, EDM, Grinding · ISO 9001, AS9100, ITAR | Sun Valley, CA | MillingTurningSwissEDMGrinding | ISO 9001, AS9100, ITAR |
| Scientific Tool Milling, Turning, Grinding | Syracuse, NY | MillingTurningGrinding | - |
| Scotia Engineering, Inc Milling, Waterjet, Bending, Welding, Stamping, EDM, Grinding, Assembly | Santa Fe Springs, CA | MillingWaterjetBendingWeldingStampingEDMGrindingAssembly | - |
| Scull Manufacturing, LLC Milling, Turning, Grinding | Olean, NY | MillingTurningGrinding | - |
| SDS Engineering Milling, Turning, Grinding · ISO 9001 | Sun Valley, CA | MillingTurningGrinding | ISO 9001 |
| Serrano Industries, Inc Milling, Turning, Swiss, EDM, Grinding · ISO 9001, AS9100 | Santa Fe Springs, CA | MillingTurningSwissEDMGrinding | ISO 9001, AS9100 |
| Service Metal Fabricators Inc Milling, Punching, Bending, Welding, Stamping, Grinding, Finishing, Assembly | Williamsburg, VA | MillingPunchingBendingWeldingStampingGrindingFinishingAssembly | - |
| Shamong Manufacturing Laser, Punching, Bending, Welding, Stamping, Grinding, Finishing, Assembly · AS9100, NADCAP | Shamong, NJ | LaserPunchingBendingWeldingStampingGrindingFinishingAssembly | AS9100, NADCAP |
| Sharp Dimension Inc Milling, Turning, Bending, Welding, Grinding, Finishing, Assembly · ISO 9001, ITAR | Fremont, CA | MillingTurningBendingWeldingGrindingFinishingAssembly | ISO 9001, ITAR |
| Shoemaker Mfg Solutions Inc Milling, Turning, Laser, Waterjet, Punching, Bending, Welding, Stamping, Grinding · ISO 9001, AS9100, ITAR, CMMC | Souderton, PA | MillingTurningLaserWaterjetPunchingBendingWeldingStampingGrinding | ISO 9001, AS9100, ITAR, CMMC |
| Short Run Pro LLC Bending, Welding, Grinding · ISO 9001 | Belmont, NC | BendingWeldingGrinding | ISO 9001 |