| South Bend Form Tool Co Milling, Turning, EDM | South Bend, IN | MillingTurningEDM | - |
| South Central Manufacturing Corp Milling, Turning, Welding, Grinding | Summersville, MO | MillingTurningWeldingGrinding | - |
| Southeastern Machine Works, Inc Milling, Turning, Welding | Live Oak, FL | MillingTurningWelding | - |
| Southern Ohio Manufacturing Milling, Turning, Laser, Bending, Welding, Grinding, Finishing | Amelia, OH | MillingTurningLaserBendingWeldingGrindingFinishing | - |
| Southern Precision, Inc Milling, Turning, Stamping | Saint Rose, LA | MillingTurningStamping | - |
| Southern Precision Machining Milling, Turning, Grinding, Finishing · ISO 9001, AS9100, ITAR | Shelbyville, TN | MillingTurningGrindingFinishing | ISO 9001, AS9100, ITAR |
| Southwest Industrial Sales LLC Milling, Turning, Swiss, Bending, Welding, EDM, Assembly · ISO 9001, AS9100, ITAR, ISO 13485, CMMC | Chandler, AZ | MillingTurningSwissBendingWeldingEDMAssembly | ISO 9001, AS9100, ITAR, ISO 13485, CMMC |
| Gulf South Machine Inc Milling, Turning | Ponchatoula, LA | MillingTurning | - |
| South Eastern Machining Inc Milling, Turning, Bending, Welding · ISO 9001 | Pelzer, SC | MillingTurningBendingWelding | ISO 9001 |
| Southeastern Machining Milling, Turning, Welding · ISO 9001 | Worthington, OH | MillingTurningWelding | ISO 9001 |
| Southwest Greene International Inc Milling, Turning, Stamping, Metal AM, EDM | Oceanside, CA | MillingTurningStampingMetal AMEDM | - |
| Southwest Precision Machining, L.L.C Milling, Turning, Swiss, Welding, Finishing | Tucson, AZ | MillingTurningSwissWeldingFinishing | - |
| Sugar River Machine Inc Milling, Turning, Welding, Grinding, Finishing, Assembly | South Beloit, IL | MillingTurningWeldingGrindingFinishingAssembly | - |
| Bertrand Products, Inc Milling, Turning, Grinding, Finishing · ISO 9001 | South Bend, IN | MillingTurningGrindingFinishing | ISO 9001 |
| C.V. Industries Milling, Turning, EDM | Southington, CT | MillingTurningEDM | - |
| Dynamic Machining Inc Milling, Turning | South Salt Lake, UT | MillingTurning | - |
| Metalogic Industries LLC Milling, Turning, Swiss, Laser, Welding, EDM, Grinding | Southbridge, MA | MillingTurningSwissLaserWeldingEDMGrinding | - |
| Midway Machine & Instrument Company Inc Milling, Turning, EDM, Finishing · ISO 9001 | South Houston, TX | MillingTurningEDMFinishing | ISO 9001 |
| Skillcraft Machine Tool Co Inc Milling, Turning, Welding | South Windsor, CT | MillingTurningWelding | - |
| The Bennu Group Inc Milling, Turning, Waterjet, Welding, Finishing · ISO 9001 | South Holland, IL | MillingTurningWaterjetWeldingFinishing | ISO 9001 |
| Whalley Precision Inc Milling, Turning, Welding, Grinding, Finishing, Assembly · ISO 9001, ITAR, CMMC | Southwick, MA | MillingTurningWeldingGrindingFinishingAssembly | ISO 9001, ITAR, CMMC |
| Dms-South/bailey Tool LLC Milling, Turning, Welding, Stamping, EDM | Lancaster, TX | MillingTurningWeldingStampingEDM | - |
| A.m.i. Engineering Co LLC Milling, Turning, Finishing · ISO 9001, ITAR | Santa Ana, CA | MillingTurningFinishing | ISO 9001, ITAR |
| Accu Die & Mold, Inc Milling, Turning, Welding, Casting, EDM | Stevensville, MI | MillingTurningWeldingCastingEDM | - |
| Advanced Precision Machining, LLC Milling, Turning, Laser, Waterjet, EDM, Assembly · AS9100, ITAR, CMMC | Costa Mesa, CA | MillingTurningLaserWaterjetEDMAssembly | AS9100, ITAR, CMMC |
| Anaheim Precision Milling, Turning, Bending, Laser, Welding, Waterjet · ISO 9001, AS9100, NADCAP | Orange, CA | MillingTurningBendingLaserWeldingWaterjet | ISO 9001, AS9100, NADCAP |
| Apex Design Technology of Alabama LLC Milling, Turning, Bending, Welding, Assembly · ISO 9001 | Decatur, AL | MillingTurningBendingWeldingAssembly | ISO 9001 |
| Caron Precision Inc Turning · ISO 9001 | Kalamazoo, MI | Turning | ISO 9001 |
| Columbia Machine Works, Inc Milling, Turning, Welding, Stamping, Casting · ISO 9001, ITAR | Columbia, TN | MillingTurningWeldingStampingCasting | ISO 9001, ITAR |
| DM Machine and Tool LLC Turning, Finishing · ISO 9001, ITAR | Ridgeway, SC | TurningFinishing | ISO 9001, ITAR |
| Exact CNC Industries Inc Milling, Turning, Swiss, Laser · ISO 9001, AS9100, ITAR | Chatsworth, CA | MillingTurningSwissLaser | ISO 9001, AS9100, ITAR |
| HPR Machine Milling, Turning | Vista, CA | MillingTurning | - |
| John Bouchard & Sons Co Turning, Welding, Stamping, Casting | Nashville, TN | TurningWeldingStampingCasting | - |
| KLM Machining, Inc Milling, Turning, Welding, Finishing | Sussex, WI | MillingTurningWeldingFinishing | - |
| Mason Dixon Fabrication LLC Milling, Turning, Welding, Assembly | Hanover, PA | MillingTurningWeldingAssembly | - |
| Partco, LLC Turning, Welding | Port Allen, LA | TurningWelding | - |
| Rig Machine Works LLC Milling, Turning, Bending, Welding, Grinding | Stevensville, MT | MillingTurningBendingWeldingGrinding | - |
| SKP Machine Enterprises LLC Milling, Turning | Monticello, KY | MillingTurning | - |
| Sonoma Industries Inc Milling, Turning, Swiss · ISO 9001, AS9100, ITAR | Bell Gardens, CA | MillingTurningSwiss | ISO 9001, AS9100, ITAR |
| Sse Steel Fabrication Milling, Turning, Bending, Welding | Saint Bernard, LA | MillingTurningBendingWelding | - |
| Stone Machine Co. Inc Milling, Turning, Grinding, Finishing | Chester, NH | MillingTurningGrindingFinishing | - |
| TL Machine, LLC Milling, Turning · ISO 9001, AS9100 | Garden Grove, CA | MillingTurning | ISO 9001, AS9100 |
| Vulcan Engineering & Manf Milling, Turning, Laser, Punching, Bending, Welding, Grinding, Finishing | Waldorf, MD | MillingTurningLaserPunchingBendingWeldingGrindingFinishing | - |