| 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 |
| Ruoff & Sons, LLC Milling, Turning, Finishing, Assembly · ISO 9001 | Runnemede, NJ | MillingTurningFinishingAssembly | ISO 9001 |
| 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 |
| Schmid Tool & Engineering Corp Milling, Turning, Swiss, Stamping, Grinding, Finishing, Assembly · ISO 9001, ITAR | Villa Park, IL | MillingTurningSwissStampingGrindingFinishingAssembly | ISO 9001, ITAR |
| Seastrom Manufacturing Co Inc Milling, Turning, Laser, Waterjet, Stamping, Finishing, Assembly · ISO 9001 | Twin Falls, ID | MillingTurningLaserWaterjetStampingFinishingAssembly | ISO 9001 |
| Serrmi Products LLC Milling, Turning, Laser, Punching, Bending, Finishing | Pittsburg, KS | MillingTurningLaserPunchingBendingFinishing | - |
| Seven Star Marine Inc Milling, Turning, Waterjet, Bending, Welding, Finishing · ISO 9001 | Newport, RI | MillingTurningWaterjetBendingWeldingFinishing | ISO 9001 |
| 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 |
| SJK Machine LLC Milling, Turning, Waterjet, Welding, EDM, Finishing | Minerva, OH | MillingTurningWaterjetWeldingEDMFinishing | - |
| 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 | - |
| Southern Ohio Manufacturing Milling, Turning, Laser, Bending, Welding, Grinding, Finishing | Amelia, OH | MillingTurningLaserBendingWeldingGrindingFinishing | - |
| Southern Precision Machining Milling, Turning, Grinding, Finishing · ISO 9001, AS9100, ITAR | Shelbyville, TN | MillingTurningGrindingFinishing | ISO 9001, AS9100, ITAR |
| Southwest Precision Machining, L.L.C Milling, Turning, Swiss, Welding, Finishing | Tucson, AZ | MillingTurningSwissWeldingFinishing | - |
| Spectrum Custom Molds & Manufacturing, Inc Milling, Turning, Laser, Welding, EDM, Grinding, Finishing, Assembly · ISO 9001 | Palmetto, FL | MillingTurningLaserWeldingEDMGrindingFinishingAssembly | ISO 9001 |
| SPM Milling, Turning, Welding, EDM, Grinding, Finishing, Assembly · ISO 9001 | Portland, OR | MillingTurningWeldingEDMGrindingFinishingAssembly | ISO 9001 |
| Spring Creek Machining, Inc Milling, Turning, Waterjet, Bending, Welding, EDM, Grinding, Finishing | Lowell, AR | MillingTurningWaterjetBendingWeldingEDMGrindingFinishing | - |
| Starn Tool & Manufacturing Company Milling, Turning, EDM, Grinding, Finishing · ISO 9001, ITAR | Meadville, PA | MillingTurningEDMGrindingFinishing | ISO 9001, ITAR |
| Steen Machining, Inc Milling, Turning, Finishing | Westminster, CO | MillingTurningFinishing | - |
| Stigtec Manufacturing Milling, Welding, EDM, Grinding, Finishing, Assembly | San Marcos, CA | MillingWeldingEDMGrindingFinishingAssembly | - |
| Straton Industries Inc Milling, Turning, Stamping, EDM, Grinding, Finishing, Assembly · AS9100, ITAR, CMMC | Stratford, CT | MillingTurningStampingEDMGrindingFinishingAssembly | AS9100, ITAR, CMMC |
| Strohwig Industries, Inc Milling, Turning, Casting, EDM, Grinding, Finishing, Assembly · ISO 9001, ITAR, CMMC | Richfield, WI | MillingTurningCastingEDMGrindingFinishingAssembly | ISO 9001, ITAR, CMMC |
| Strong Forge & Fabrication, LLC Milling, Bending, Welding, Finishing | Batavia, NY | MillingBendingWeldingFinishing | - |
| Subtract LLC Milling, Turning, Swiss, Laser, Waterjet, Welding, EDM, Finishing | Muncie, IN | MillingTurningSwissLaserWaterjetWeldingEDMFinishing | - |
| Summit Machine Company Milling, Turning, Welding, Finishing · ISO 9001 | Alverton, PA | MillingTurningWeldingFinishing | ISO 9001 |
| Summit Products Inc Milling, Bending, Welding, Finishing | Altoona, IA | MillingBendingWeldingFinishing | - |
| Support Equipment Inc Milling, Turning, Welding, EDM, Finishing, Assembly · ISO 9001, AS9100, ITAR | Escondido, CA | MillingTurningWeldingEDMFinishingAssembly | ISO 9001, AS9100, ITAR |
| Swift Industries Inc Milling, Laser, Punching, Bending, Welding, Stamping, Grinding, Finishing, Assembly · ISO 9001 | Suwanee, GA | MillingLaserPunchingBendingWeldingStampingGrindingFinishingAssembly | ISO 9001 |
| Sycamore Precision, Inc Milling, Casting, Finishing | Genoa, IL | MillingCastingFinishing | - |
| T.R. Reed Enterprises Inc Milling, Turning, Finishing · ISO 9001, AS9100 | Ponder, TX | MillingTurningFinishing | ISO 9001, AS9100 |
| Tabet Manufacturing Co Inc Milling, Turning, Laser, Waterjet, Punching, Bending, Welding, Finishing, Assembly · ISO 9001, ITAR | Norfolk, VA | MillingTurningLaserWaterjetPunchingBendingWeldingFinishingAssembly | ISO 9001, ITAR |
| Tec Inc Milling, Turning, Swiss, Laser, Punching, Bending, Welding, Finishing, Assembly · ISO 9001 | Frederick, MD | MillingTurningSwissLaserPunchingBendingWeldingFinishingAssembly | ISO 9001 |
| Tech Five Machining LLC Milling, Turning, Finishing · ISO 9001, AS9100, ITAR | Tempe, AZ | MillingTurningFinishing | ISO 9001, AS9100, ITAR |
| Tech Met Inc Milling, Finishing · NADCAP | Glassport, PA | MillingFinishing | NADCAP |
| Techcraft Precision Milling, Finishing · AS9100, ITAR, CMMC | Bellingham, WA | MillingFinishing | AS9100, ITAR, CMMC |
| Tel-X Corporation Milling, Turning, Laser, Welding, Stamping, EDM, Finishing · ISO 9001, IATF 16949 | Garden City, MI | MillingTurningLaserWeldingStampingEDMFinishing | ISO 9001, IATF 16949 |
| Third Reef Machining and Engineering Ltd. Co Milling, Bending, Welding, Finishing | Cottonwood Heights, UT | MillingBendingWeldingFinishing | - |
| Tiger Precision Machining Milling, Turning, Welding, Finishing | Lodi, CA | MillingTurningWeldingFinishing | - |
| TMS Inc Milling, Laser, Punching, Bending, Welding, Grinding, Finishing, Assembly | New Berlin, WI | MillingLaserPunchingBendingWeldingGrindingFinishingAssembly | - |
| TNT Machining LLC Milling, Turning, Grinding, Finishing | Sumas, WA | MillingTurningGrindingFinishing | - |
| Toolex Corp Milling, Welding, EDM, Grinding, Finishing | Addison, IL | MillingWeldingEDMGrindingFinishing | - |
| Top Machining, Inc Milling, Turning, Welding, Finishing, Assembly · ISO 9001, AS9100, ITAR | Santa Clara, CA | MillingTurningWeldingFinishingAssembly | ISO 9001, AS9100, ITAR |
| Top Notch Machining, Inc Milling, Waterjet, Stamping, Finishing, Assembly · ISO 9001 | Gresham, OR | MillingWaterjetStampingFinishingAssembly | ISO 9001 |
| Topocut, LLC Milling, Laser, Bending, Finishing | Berthoud, CO | MillingLaserBendingFinishing | - |
| Tozli Machine Milling, Welding, Finishing · ISO 9001, ITAR, CMMC | Surprise, AZ | MillingWeldingFinishing | ISO 9001, ITAR, CMMC |