| Sanders Metal Products Inc Milling, Turning, Bending, Welding | Fargo, ND | MillingTurningBendingWelding | - |
| Selway Machine Tool Co Inc Milling, Turning, Metal AM | Salt Lake City, UT | MillingTurningMetal AM | - |
| Sepco Erie Milling, Turning, Stamping · ISO 9001 | Erie, PA | MillingTurningStamping | ISO 9001 |
| Shamrock Machining Inc Milling, Turning, Bending, Laser, Welding · ISO 9001 | Spokane Valley, WA | MillingTurningBendingLaserWelding | ISO 9001 |
| Sharp Tool Manufacturing Milling, Turning, Welding · ISO 9001, AS9100, ITAR, CMMC | Ogden, UT | MillingTurningWelding | ISO 9001, AS9100, ITAR, CMMC |
| Skamar Machine Milling, Turning · ISO 9001 | Cleveland, OH | MillingTurning | ISO 9001 |
| Slim Haney Machining Inc Milling, Turning, Welding | Tulsa, OK | MillingTurningWelding | - |
| Solvers Manufacturing Turning, Bending, Welding | Springfield, NE | TurningBendingWelding | - |
| South Bend Form Tool Co Milling, Turning, EDM | South Bend, IN | MillingTurningEDM | - |
| SRS Fabrication Inc. Milling, Turning, Bending, Welding, Waterjet | North Las Vegas, NV | MillingTurningBendingWeldingWaterjet | - |
| Summit City Precision Machining LLC Milling, Turning, EDM · ISO 9001 | Fort Wayne, IN | MillingTurningEDM | ISO 9001 |
| Superior Machine & Tool Milling, Turning, Welding · ISO 9001 | Fort Wayne, IN | MillingTurningWelding | ISO 9001 |
| Superior Process Solutions Milling, Turning, Bending, Laser, Welding, Metal AM | Springfield, MO | MillingTurningBendingLaserWeldingMetal AM | - |
| Swan Island Sheet Metal Works Turning, Bending, Laser, Welding | Portland, OR | TurningBendingLaserWelding | - |
| Tampa Bay Machining Milling, Turning, Welding, EDM · ISO 9001, AS9100, ITAR | Tampa, FL | MillingTurningWeldingEDM | ISO 9001, AS9100, ITAR |
| TCMS Inc Milling, Turning, Welding | Oklahoma City, OK | MillingTurningWelding | - |
| TEKE Machine Corporation Milling, Turning · ISO 9001, AS9100 | Rochester, NY | MillingTurning | ISO 9001, AS9100 |
| Teton Machine Co Milling, Turning · ISO 9001, AS9100, ITAR | Payette, ID | MillingTurning | ISO 9001, AS9100, ITAR |
| The Gent Machine Company Milling, Turning · ISO 9001, IATF 16949 | Cleveland, OH | MillingTurning | ISO 9001, IATF 16949 |
| Theonics Milling, Turning, Bending, Welding, EDM · AS9100, ITAR, ISO 13485 | Huntsville, AL | MillingTurningBendingWeldingEDM | AS9100, ITAR, ISO 13485 |
| Tolerance Tool & Engineering Milling, Turning, Welding · ISO 9001, ITAR | Detroit, MI | MillingTurningWelding | ISO 9001, ITAR |
| Tri-Gon Precision, Inc. Milling, Turning, Welding, EDM | Colorado Springs, CO | MillingTurningWeldingEDM | - |
| Tri-V Tool & Manufacturing Co Milling, Turning, Bending, Welding, Waterjet, EDM · ISO 9001 | Omaha, NE | MillingTurningBendingWeldingWaterjetEDM | ISO 9001 |
| Triple E Machine Inc Turning, Laser, Welding, Waterjet, EDM | Appleton, WI | TurningLaserWeldingWaterjetEDM | - |
| TRK Fabrication Milling, Turning, Bending, Welding, Waterjet | Akron, OH | MillingTurningBendingWeldingWaterjet | - |
| True FAB and Powder Turning, Bending, Laser, Welding | Reno, NV | TurningBendingLaserWelding | - |
| Turner Machine Co Inc Milling, Turning, Welding | Tulsa, OK | MillingTurningWelding | - |
| United Grinding & Machine Co Milling, Turning, Bending, Laser, Welding, Waterjet, EDM, Casting · ISO 9001 | Canton, OH | MillingTurningBendingLaserWeldingWaterjetEDMCasting | ISO 9001 |
| United Machine & Tool Milling, Turning, Laser, Welding · ISO 9001 | Goodlettsville, TN | MillingTurningLaserWelding | ISO 9001 |
| United Precision Machining Milling, Turning | Minneapolis, MN | MillingTurning | - |
| United Precision Services Milling, Turning, Bending, Welding, Waterjet | Cincinnati, OH | MillingTurningBendingWeldingWaterjet | - |
| USA Precision Machining Milling, Turning · ISO 9001 | Houston, TX | MillingTurning | ISO 9001 |
| Veco Technologies, Inc. Milling, Turning, Welding, EDM | Fresno, CA | MillingTurningWeldingEDM | - |
| Vulcan Machine Milling, Turning, Bending, Laser, Welding, EDM · ISO 9001, AS9100, ITAR, ISO 13485, CMMC | Tampa, FL | MillingTurningBendingLaserWeldingEDM | ISO 9001, AS9100, ITAR, ISO 13485, CMMC |
| Washington Machine Works Milling, Turning, Bending, Welding · ISO 9001 | Seattle, WA | MillingTurningBendingWelding | ISO 9001 |
| Wildman Manufacturing, Inc. Milling, Turning, Bending, Welding | Oklahoma City, OK | MillingTurningBendingWelding | - |
| Wolfe & Swickard Machine Co Milling, Turning · AS9100 | Indianapolis, IN | MillingTurning | AS9100 |
| Wrightwood Precision Products Company Milling, Turning | Chicago, IL | MillingTurning | - |
| Xymat Milling, Turning, Bending, Laser, Welding, Waterjet, EDM, Metal AM · ISO 9001, AS9100 | Colorado Springs, CO | MillingTurningBendingLaserWeldingWaterjetEDMMetal AM | ISO 9001, AS9100 |
| ZYCI CNC Machining Milling, Turning, EDM, Metal AM · ISO 9001, AS9100, ITAR, CMMC | Chamblee, GA | MillingTurningEDMMetal AM | ISO 9001, AS9100, ITAR, CMMC |