| Carlisle Machine Works Inc Milling, Turning, Bending, Welding, EDM, Grinding | Millville, NJ | MillingTurningBendingWeldingEDMGrinding | - |
| Carlson Tool & Manufacturing Corp Milling, Turning, EDM, Grinding | Cedarburg, WI | MillingTurningEDMGrinding | - |
| Carr Machine & Tool, Inc Milling, Grinding, Assembly · ISO 9001, ITAR, CMMC | Elk Grove Village, IL | MillingGrindingAssembly | ISO 9001, ITAR, CMMC |
| Center Tool Co Milling, Turning, Welding, Stamping, EDM, Grinding · ISO 9001 | Hampshire, IL | MillingTurningWeldingStampingEDMGrinding | ISO 9001 |
| Central Precision Inc Milling, Laser, Punching, Bending, Welding, Grinding, Finishing · ISO 9001 | Boonsboro, MD | MillingLaserPunchingBendingWeldingGrindingFinishing | ISO 9001 |
| Century Tool Co Inc Milling, Turning, Welding, EDM, Grinding | Thompson, CT | MillingTurningWeldingEDMGrinding | - |
| Century Tool Inc Milling, Welding, EDM, Grinding, Finishing, Assembly · ISO 9001 | Rogers, MN | MillingWeldingEDMGrindingFinishingAssembly | ISO 9001 |
| Chapco, Inc Laser, Punching, Bending, Welding, Grinding, Finishing, Assembly · ISO 9001, ITAR, CMMC | Deep River, CT | LaserPunchingBendingWeldingGrindingFinishingAssembly | ISO 9001, ITAR, CMMC |
| Charles Meisner, Inc Milling, Turning, Bending, Welding, Stamping, EDM, Grinding · ISO 9001, AS9100 | Upland, CA | MillingTurningBendingWeldingStampingEDMGrinding | ISO 9001, AS9100 |
| Checkered Past Machine Milling, Turning, Welding, Grinding · ISO 9001, CMMC | Brownsburg, IN | MillingTurningWeldingGrinding | ISO 9001, CMMC |
| Chick Machine Company, LLC Milling, Turning, Waterjet, Grinding, Finishing · ISO 9001, AS9100, ITAR | Butler, PA | MillingTurningWaterjetGrindingFinishing | ISO 9001, AS9100, ITAR |
| Class A Tooling Inc Milling, Turning, Bending, Welding, Stamping, EDM, Grinding | Cabot, AR | MillingTurningBendingWeldingStampingEDMGrinding | - |
| Classic Machine & Engineering Milling, Turning, Laser, Welding, Grinding | Ashland, VA | MillingTurningLaserWeldingGrinding | - |
| CNC Machine and Fabrication, Inc Laser, Waterjet, Punching, Bending, Welding, Stamping, Grinding, Finishing | Hyde Park, UT | LaserWaterjetPunchingBendingWeldingStampingGrindingFinishing | - |
| CNC Manufacturing Inc Milling, Turning, Swiss, Laser, Grinding · ISO 9001 | Coatesville, PA | MillingTurningSwissLaserGrinding | ISO 9001 |
| CNC Specialties Manufacturing Inc Milling, Turning, Bending, Welding, EDM, Grinding, Finishing | Apollo, PA | MillingTurningBendingWeldingEDMGrindingFinishing | - |
| Collins Machine Works Welding, Grinding · CMMC | Portsmouth, VA | WeldingGrinding | CMMC |
| Commercial Tool & Die Inc Milling, Turning, Welding, Grinding | Marshall, VA | MillingTurningWeldingGrinding | - |
| Connelly Machine WKS Milling, Turning, Waterjet, Welding, Grinding · ISO 9001, ITAR | Santa Ana, CA | MillingTurningWaterjetWeldingGrinding | ISO 9001, ITAR |
| Conner Brothers Machine Co., Inc Milling, Turning, Welding, Grinding · ISO 9001 | Bessemer City, NC | MillingTurningWeldingGrinding | ISO 9001 |
| Conroe Machine, LLC Milling, Turning, Laser, Bending, Welding, EDM, Grinding, Finishing · ISO 9001 | Conroe, TX | MillingTurningLaserBendingWeldingEDMGrindingFinishing | ISO 9001 |
| Conti Tool & Die, Inc Milling, Turning, Bending, Welding, Grinding | Akron, OH | MillingTurningBendingWeldingGrinding | - |
| Copen Machine, Inc Milling, Turning, Swiss, Welding, Grinding · ISO 9001 | Kent, OH | MillingTurningSwissWeldingGrinding | ISO 9001 |
| Crater Industries LLC Milling, Turning, EDM, Grinding, Assembly | Santa Clarita, CA | MillingTurningEDMGrindingAssembly | - |
| Creative Machining Systems Inc Milling, Turning, Welding, EDM, Grinding, Finishing | Trenton, NJ | MillingTurningWeldingEDMGrindingFinishing | - |
| Critical Defense Inc Milling, Turning, Bending, Welding, Grinding, Assembly | Windber, PA | MillingTurningBendingWeldingGrindingAssembly | - |
| Cubitek, Inc Milling, Turning, EDM, Grinding · ISO 9001, AS9100 | Brentwood, NY | MillingTurningEDMGrinding | ISO 9001, AS9100 |
| Cuddeback Machining, Inc Milling, Turning, Laser, Welding, Stamping, EDM, Grinding · ISO 9001 | Hilton, NY | MillingTurningLaserWeldingStampingEDMGrinding | ISO 9001 |
| Custom Machine Milling, Turning, Welding, Grinding | Hagerstown, MD | MillingTurningWeldingGrinding | - |
| Custom Machine & Design Inc Milling, Turning, Waterjet, Welding, EDM, Grinding | Lincoln, NE | MillingTurningWaterjetWeldingEDMGrinding | - |
| Custom Machine Works LLC Milling, Turning, Stamping, Grinding | Fenton, MO | MillingTurningStampingGrinding | - |
| Cutco Metal Sawing LLC Milling, Turning, Welding, Grinding | Burleson, TX | MillingTurningWeldingGrinding | - |
| Cutting Solutions Turning, Laser, Waterjet, Bending, Welding, Grinding, Finishing, Assembly | Zeeland, MI | TurningLaserWaterjetBendingWeldingGrindingFinishingAssembly | - |
| D & D Manufacturing LLC Milling, Turning, Grinding | Ipswich, MA | MillingTurningGrinding | - |
| D & H Industries Inc Milling, Turning, Laser, Bending, Welding, Stamping, Grinding, Finishing · ISO 9001, ITAR | Oconomowoc, WI | MillingTurningLaserBendingWeldingStampingGrindingFinishing | ISO 9001, ITAR |
| D&F Screw Machine Products Turning, Waterjet, Grinding · ISO 9001 | East Hanover, NJ | TurningWaterjetGrinding | ISO 9001 |
| Daico Precision LLC Milling, Turning, Grinding, Finishing, Assembly | Garden Grove, CA | MillingTurningGrindingFinishingAssembly | - |
| Dailey's CNC Machining LLC Milling, EDM, Grinding · ISO 9001, AS9100, ITAR | Columbus, IN | MillingEDMGrinding | ISO 9001, AS9100, ITAR |
| Dalton Manufacturing Group Inc Milling, Turning, Grinding · ISO 9001, CMMC | Amesbury, MA | MillingTurningGrinding | ISO 9001, CMMC |
| Danco Precision, Inc Milling, Turning, Laser, Welding, Stamping, EDM, Grinding, Assembly · ISO 9001, AS9100, ITAR | Phoenixville, PA | MillingTurningLaserWeldingStampingEDMGrindingAssembly | ISO 9001, AS9100, ITAR |
| David Packard Company, Inc Milling, Turning, Swiss, Grinding, Finishing, Assembly · ISO 9001, ITAR | Oxford, MA | MillingTurningSwissGrindingFinishingAssembly | ISO 9001, ITAR |
| Davis Tool & Die, Inc Milling, Turning, Welding, Stamping, EDM, Grinding | Abbeville, MS | MillingTurningWeldingStampingEDMGrinding | - |
| Dearborn Bortec LLC Milling, Turning, Waterjet, Welding, EDM, Grinding, Finishing · ISO 9001, AS9100, ITAR | Fryeburg, ME | MillingTurningWaterjetWeldingEDMGrindingFinishing | ISO 9001, AS9100, ITAR |
| Dearborn, Inc Milling, Grinding | Berea, OH | MillingGrinding | - |
| Decker Machine Works Inc Milling, Turning, Swiss, EDM, Grinding · ISO 9001, AS9100, ITAR | Greenfield, MA | MillingTurningSwissEDMGrinding | ISO 9001, AS9100, ITAR |
| Defelice Engineering, Inc Milling, Turning, Bending, Welding, Casting, Grinding | Mooresville, IN | MillingTurningBendingWeldingCastingGrinding | - |
| Delta Machine Company, LLC Milling, Turning, Welding, Grinding | Harbor City, CA | MillingTurningWeldingGrinding | - |
| Denny Grice Inc Turning, Swiss, Grinding, Finishing | Three Rivers, MI | TurningSwissGrindingFinishing | - |
| Deperini Metal Fabricators Milling, Laser, Punching, Bending, Welding, Grinding, Finishing · ISO 9001 | Gaithersburg, MD | MillingLaserPunchingBendingWeldingGrindingFinishing | ISO 9001 |
| Desert Engineering Group Inc Milling, Turning, Stamping, Grinding | Tucson, AZ | MillingTurningStampingGrinding | - |