| SendCutSend Milling, Bending, Laser, Welding, Waterjet | Reno, NV | MillingBendingLaserWeldingWaterjet | - |
| Sequoia Machine Works LLC Milling, Turning, Laser, Punching, Welding, Finishing | Sandy, OR | MillingTurningLaserPunchingWeldingFinishing | - |
| 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 |
| SF Industries USA Laser, Bending, Welding | Brenham, TX | LaserBendingWelding | - |
| SFC Tec, Inc Milling, Turning, Laser, Bending, Welding | Delta, UT | MillingTurningLaserBendingWelding | - |
| 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 | - |
| Sheet Metal Solutions Inc Welding, Finishing | Tangent, OR | WeldingFinishing | - |
| Sheetmetal Engineering Inc Milling, Laser, Punching, Bending, Welding · ISO 9001, AS9100 | Simi Valley, CA | MillingLaserPunchingBendingWelding | ISO 9001, AS9100 |
| 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 |
| Silicon Valley Precision Inc Milling, Turning, Welding, Casting, Grinding, Finishing · ITAR | Livermore, CA | MillingTurningWeldingCastingGrindingFinishing | ITAR |
| Sintel Inc Laser, Punching, Bending, Welding, Finishing, Assembly | Spring Lake, MI | LaserPunchingBendingWeldingFinishingAssembly | - |
| SJK Machine LLC Milling, Turning, Waterjet, Welding, EDM, Finishing | Minerva, OH | MillingTurningWaterjetWeldingEDMFinishing | - |
| Smith Metal, LLC Milling, Turning, Swiss, Laser, Waterjet, Bending, Welding, EDM, Grinding, Finishing · ISO 9001 | Augusta, MI | MillingTurningSwissLaserWaterjetBendingWeldingEDMGrindingFinishing | ISO 9001 |
| Soflo Machining Milling, Turning, Laser, Waterjet, Welding, Grinding, Finishing · ISO 9001, AS9100 | Coral Springs, FL | MillingTurningLaserWaterjetWeldingGrindingFinishing | ISO 9001, AS9100 |
| Soteria LLC Milling, Turning, Welding, Grinding, Finishing | Anniston, AL | MillingTurningWeldingGrindingFinishing | - |
| Southern Ohio Manufacturing Milling, Turning, Laser, Bending, Welding, Grinding, Finishing | Amelia, OH | MillingTurningLaserBendingWeldingGrindingFinishing | - |
| Southwest Precision Machining, L.L.C Milling, Turning, Swiss, Welding, Finishing | Tucson, AZ | MillingTurningSwissWeldingFinishing | - |
| SP Manufacturing Inc Milling, Turning, Welding, Finishing · ISO 9001, AS9100 | Livermore, CA | MillingTurningWeldingFinishing | ISO 9001, AS9100 |
| Sparton Technology Corp Milling, Turning, Laser, Punching, Bending, Welding, Finishing, Assembly · ISO 9001, AS9100 | Hudson, NH | MillingTurningLaserPunchingBendingWeldingFinishingAssembly | ISO 9001, AS9100 |
| Specialty Tool & Die Company Inc Milling, Turning, Bending, Welding, Stamping, Grinding, Assembly | Kokomo, IN | MillingTurningBendingWeldingStampingGrindingAssembly | - |
| 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 | - |
| Spring Grove Sheet Metal Bending, Laser, Welding | Cincinnati, OH | BendingLaserWelding | - |
| Standard Machine, LLC Milling, Turning, Welding, Casting, Grinding, Finishing | Cleveland, OH | MillingTurningWeldingCastingGrindingFinishing | - |
| Steel-Craft Corp. of Hartford Milling, Laser, Punching, Bending, Welding, Stamping, Finishing | Hartford, WI | MillingLaserPunchingBendingWeldingStampingFinishing | - |
| Stigtec Manufacturing Milling, Welding, EDM, Grinding, Finishing, Assembly | San Marcos, CA | MillingWeldingEDMGrindingFinishingAssembly | - |
| Subtract LLC Milling, Turning, Swiss, Laser, Waterjet, Welding, EDM, Finishing | Muncie, IN | MillingTurningSwissLaserWaterjetWeldingEDMFinishing | - |
| Sugar River Machine Inc Milling, Turning, Welding, Grinding, Finishing, Assembly | South Beloit, IL | MillingTurningWeldingGrindingFinishingAssembly | - |
| Summit Machine Company Milling, Turning, Welding, Finishing · ISO 9001 | Alverton, PA | MillingTurningWeldingFinishing | ISO 9001 |
| Summit Machining Co., Ltd Milling, Turning, Welding, Stamping, Casting, Finishing | Mogadore, OH | MillingTurningWeldingStampingCastingFinishing | - |
| Summit Products Inc Milling, Bending, Welding, Finishing | Altoona, IA | MillingBendingWeldingFinishing | - |
| Superior Process Solutions Milling, Turning, Bending, Laser, Welding, Metal AM | Springfield, MO | MillingTurningBendingLaserWeldingMetal AM | - |
| Superior Technology Inc Milling, Turning, Swiss, Welding, Grinding, Finishing, Assembly · ISO 9001 | Rochester, NY | MillingTurningSwissWeldingGrindingFinishingAssembly | ISO 9001 |
| Support Equipment Inc Milling, Turning, Welding, EDM, Finishing, Assembly · ISO 9001, AS9100, ITAR | Escondido, CA | MillingTurningWeldingEDMFinishingAssembly | ISO 9001, AS9100, ITAR |
| T & D Specialties Milling, Turning, Swiss, Welding, Finishing · ISO 9001 | Oxford, MA | MillingTurningSwissWeldingFinishing | ISO 9001 |
| Tabet Manufacturing Co Inc Milling, Turning, Laser, Waterjet, Punching, Bending, Welding, Finishing, Assembly · ISO 9001, ITAR | Norfolk, VA | MillingTurningLaserWaterjetPunchingBendingWeldingFinishingAssembly | ISO 9001, ITAR |
| Tag Team Manufacturing Turning, Welding, Finishing · ISO 9001 | Parker, CO | TurningWeldingFinishing | ISO 9001 |
| Tahl Inc Milling, Turning, Welding, EDM, Grinding, Finishing · ISO 9001, ITAR, CMMC | Tucson, AZ | MillingTurningWeldingEDMGrindingFinishing | ISO 9001, ITAR, CMMC |
| Tamra Group Inc Laser, Welding | Mansfield, TX | LaserWelding | - |
| Tanksley Machine & Tool, Inc Milling, Turning, Laser, Welding, EDM, Grinding · AS9100 | Decatur, AL | MillingTurningLaserWeldingEDMGrinding | AS9100 |
| Tec Inc Milling, Turning, Swiss, Laser, Punching, Bending, Welding, Finishing, Assembly · ISO 9001 | Frederick, MD | MillingTurningSwissLaserPunchingBendingWeldingFinishingAssembly | ISO 9001 |
| Technical Concepts LLC Milling, Turning, Laser, Bending, Welding | Hollywood, AL | MillingTurningLaserBendingWelding | - |
| Tel-X Corporation Milling, Turning, Laser, Welding, Stamping, EDM, Finishing · ISO 9001, IATF 16949 | Garden City, MI | MillingTurningLaserWeldingStampingEDMFinishing | ISO 9001, IATF 16949 |
| Teltron Engineering, Inc Laser, Punching, Bending, Welding, Assembly · AS9100, ITAR, CMMC | Taunton, MA | LaserPunchingBendingWeldingAssembly | AS9100, ITAR, CMMC |
| Tennessee Tool Works LLC Milling, Turning, Laser, Waterjet, Bending, Welding, Stamping, EDM, Grinding | Murfreesboro, TN | MillingTurningLaserWaterjetBendingWeldingStampingEDMGrinding | - |
| Texarkana Machine Inc Milling, Turning, Waterjet, Welding, Grinding, Finishing | Texarkana, TX | MillingTurningWaterjetWeldingGrindingFinishing | - |
| The Flinchbaugh Company, Inc Milling, Turning, Welding, EDM, Grinding, Finishing, Assembly | Manchester, PA | MillingTurningWeldingEDMGrindingFinishingAssembly | - |