| 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 |
| Rie Coatings, LLC Stamping, Finishing · ISO 9001, AS9100 | Albuquerque, NM | StampingFinishing | ISO 9001, AS9100 |
| 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 |
| Roaring Creek Machine Co Milling, Turning, Laser, Bending, Welding, Finishing · ITAR | Catawissa, PA | MillingTurningLaserBendingWeldingFinishing | ITAR |
| Rocky Mountain Waterjet, LLC Laser, Waterjet, Bending, Welding, Finishing | Greeley, CO | LaserWaterjetBendingWeldingFinishing | - |
| Roller Technologies Co Milling, Turning, Welding, Finishing, Assembly | Upland, CA | MillingTurningWeldingFinishingAssembly | - |
| Ross Manufacturing, Inc Milling, Turning, Laser, Bending, Welding, Finishing | Saint Francis, KS | MillingTurningLaserBendingWeldingFinishing | - |
| Roush & Yates Racing Engines LLC Milling, Turning, Swiss, Waterjet, Finishing · AS9100, ITAR, NADCAP, ISO 13485 | Mooresville, NC | MillingTurningSwissWaterjetFinishing | AS9100, ITAR, NADCAP, ISO 13485 |
| Royal Coatings Grinding, Finishing | Simi Valley, CA | GrindingFinishing | - |
| Ruoff & Sons, LLC Milling, Turning, Finishing, Assembly · ISO 9001 | Runnemede, NJ | MillingTurningFinishingAssembly | ISO 9001 |
| S & R Sheet Metal, Inc Laser, Punching, Bending, Welding, Finishing | Kelso, WA | LaserPunchingBendingWeldingFinishing | - |
| S&B Metal Products of Daytona LLC Laser, Punching, Bending, Welding, Finishing | Daytona Beach, FL | LaserPunchingBendingWeldingFinishing | - |
| Saar Corp Milling, Turning, Swiss, Finishing, Assembly · AS9100 | Farmington, CT | MillingTurningSwissFinishingAssembly | AS9100 |
| Saliga Machine Co Inc Milling, Bending, Welding, Stamping, EDM, Finishing · ISO 9001 | Hudson, MA | MillingBendingWeldingStampingEDMFinishing | ISO 9001 |
| Saporito Finishing Co Welding, Finishing · NADCAP | Cicero, IL | WeldingFinishing | NADCAP |
| Sapphire Metal Finishing, Inc Finishing · ISO 9001, NADCAP | Caldwell, ID | Finishing | ISO 9001, NADCAP |
| Savage Machining Inc Milling, Turning, EDM, Finishing, Assembly · ISO 9001 | Simi Valley, CA | MillingTurningEDMFinishingAssembly | ISO 9001 |
| Sawyer Manufacturing Company Turning, Welding, Finishing | Tulsa, OK | TurningWeldingFinishing | - |
| 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 |
| Schulte Corporation Milling, Turning, Welding, Finishing · NADCAP | San Clemente, CA | MillingTurningWeldingFinishing | NADCAP |
| Seastrom Manufacturing Co Inc Milling, Turning, Laser, Waterjet, Stamping, Finishing, Assembly · ISO 9001 | Twin Falls, ID | MillingTurningLaserWaterjetStampingFinishingAssembly | ISO 9001 |
| Seconn Fabrication LLC Laser, Punching, Bending, Welding, Finishing | Waterford, CT | LaserPunchingBendingWeldingFinishing | - |
| Seminole Metal Finishing, Inc Finishing | Altamonte Springs, FL | Finishing | - |
| Sequoia Machine Works LLC Milling, Turning, Laser, Punching, Welding, Finishing | Sandy, OR | MillingTurningLaserPunchingWeldingFinishing | - |
| Serrmi Products LLC Milling, Turning, Laser, Punching, Bending, Finishing | Pittsburg, KS | MillingTurningLaserPunchingBendingFinishing | - |
| Service Metal Fabricators Inc Milling, Punching, Bending, Welding, Stamping, Grinding, Finishing, Assembly | Williamsburg, VA | MillingPunchingBendingWeldingStampingGrindingFinishingAssembly | - |
| Seven Star Marine Inc Milling, Turning, Waterjet, Bending, Welding, Finishing · ISO 9001 | Newport, RI | MillingTurningWaterjetBendingWeldingFinishing | ISO 9001 |
| Shamong Manufacturing Laser, Punching, Bending, Welding, Stamping, Grinding, Finishing, Assembly · AS9100, NADCAP | Shamong, NJ | LaserPunchingBendingWeldingStampingGrindingFinishingAssembly | AS9100, NADCAP |
| Shape Shifters Inc Milling, Waterjet, Bending, Welding, Stamping, Finishing | Bloomfield, IN | MillingWaterjetBendingWeldingStampingFinishing | - |
| Sharp Dimension Inc Milling, Turning, Bending, Welding, Grinding, Finishing, Assembly · ISO 9001, ITAR | Fremont, CA | MillingTurningBendingWeldingGrindingFinishingAssembly | ISO 9001, ITAR |
| Sheet Metal Solutions Inc Welding, Finishing | Tangent, OR | WeldingFinishing | - |
| Shieldcoat Technologies Inc Finishing, Assembly · ISO 9001, ITAR | Lufkin, TX | FinishingAssembly | ISO 9001, ITAR |
| Sifco Industries Inc Forging, Finishing, Assembly · ISO 9001, NADCAP | Cleveland, OH | ForgingFinishingAssembly | ISO 9001, NADCAP |
| Silicon Valley Precision Inc Milling, Turning, Welding, Casting, Grinding, Finishing · ITAR | Livermore, CA | MillingTurningWeldingCastingGrindingFinishing | ITAR |
| Silver Creek Machine Ltd Milling, Turning, Bending, Finishing · ISO 9001 | Fort Worth, TX | MillingTurningBendingFinishing | ISO 9001 |
| Sintel Inc Laser, Punching, Bending, Welding, Finishing, Assembly | Spring Lake, MI | LaserPunchingBendingWeldingFinishingAssembly | - |
| SJD Machining, Inc Milling, Turning, EDM, Grinding, Finishing | Meadville, PA | MillingTurningEDMGrindingFinishing | - |
| SJK Machine LLC Milling, Turning, Waterjet, Welding, EDM, Finishing | Minerva, OH | MillingTurningWaterjetWeldingEDMFinishing | - |
| Slagel Manufacturing, Inc Bending, Welding, Finishing · ISO 9001 | Forrest, IL | BendingWeldingFinishing | ISO 9001 |
| Smith Metal, LLC Milling, Turning, Swiss, Laser, Waterjet, Bending, Welding, EDM, Grinding, Finishing · ISO 9001 | Augusta, MI | MillingTurningSwissLaserWaterjetBendingWeldingEDMGrindingFinishing | ISO 9001 |
| Snowline Engineering Laser, Waterjet, Welding, Finishing · ISO 9001, AS9100, NADCAP | Cameron Park, CA | LaserWaterjetWeldingFinishing | ISO 9001, AS9100, NADCAP |
| Soflo Machining Milling, Turning, Laser, Waterjet, Welding, Grinding, Finishing · ISO 9001, AS9100 | Coral Springs, FL | MillingTurningLaserWaterjetWeldingGrindingFinishing | ISO 9001, AS9100 |
| Solidiform, Inc Milling, Casting, Finishing | Fort Worth, TX | MillingCastingFinishing | - |
| Sonic Aerospace Inc Milling, Turning, Grinding, Finishing, Assembly · ISO 9001, AS9100 | Chandler, AZ | MillingTurningGrindingFinishingAssembly | ISO 9001, AS9100 |
| Sonic Manufacturing Corporation Milling, Welding, EDM, Grinding, Finishing, Assembly · AS9100, NADCAP | Elk Grove Village, IL | MillingWeldingEDMGrindingFinishingAssembly | AS9100, NADCAP |
| Soteria LLC Milling, Turning, Welding, Grinding, Finishing | Anniston, AL | MillingTurningWeldingGrindingFinishing | - |