| Busch Brothers Milling, Turning, Swiss, Finishing | New Prague, MN | MillingTurningSwissFinishing | - |
| C & W Manufacturing Milling, Turning, Welding, Grinding, Finishing · ISO 9001, ITAR, CMMC | Turlock, CA | MillingTurningWeldingGrindingFinishing | ISO 9001, ITAR, CMMC |
| C.E. Machine Company, Inc. Milling, Waterjet, Metal AM · ISO 9001, AS9100 | Wichita, KS | MillingWaterjetMetal AM | ISO 9001, AS9100 |
| C&M Precision Tech Milling, Turning, Swiss, Welding, EDM, Grinding, Finishing · ISO 9001, AS9100, ITAR, ISO 13485, CMMC | Hudson, NH | MillingTurningSwissWeldingEDMGrindingFinishing | ISO 9001, AS9100, ITAR, ISO 13485, CMMC |
| California Lasers Inc Milling, Laser, Welding, EDM, Grinding | Simi Valley, CA | MillingLaserWeldingEDMGrinding | - |
| Callacore LLC Milling, Turning, Grinding · AS9100 | Hutchinson, KS | MillingTurningGrinding | AS9100 |
| Canady Manufacturing Co Inc Milling, Turning, EDM, Grinding · ISO 9001 | San Fernando, CA | MillingTurningEDMGrinding | ISO 9001 |
| Catamount Machine Works Milling, Turning, EDM · AS9100, ITAR, CMMC | Plant City, FL | MillingTurningEDM | AS9100, ITAR, CMMC |
| CB Manufacturing & Engineering Inc Milling, Turning, EDM · ISO 9001, AS9100 | Santa Ana, CA | MillingTurningEDM | ISO 9001, AS9100 |
| Center Tool Co Milling, Turning, Welding, Stamping, EDM, Grinding · ISO 9001 | Hampshire, IL | MillingTurningWeldingStampingEDMGrinding | ISO 9001 |
| Cherry Creek Machine, LLC Milling, Turning, Waterjet, Welding · ISO 9001 | Tulsa, OK | MillingTurningWaterjetWelding | ISO 9001 |
| Chesapeake Machine Co Milling, Welding | Baltimore, MD | MillingWelding | - |
| Class A Tooling Inc Milling, Turning, Bending, Welding, Stamping, EDM, Grinding | Cabot, AR | MillingTurningBendingWeldingStampingEDMGrinding | - |
| Classic Engineering, LLC Milling, Turning, Waterjet, Welding, Finishing | Gloucester, MA | MillingTurningWaterjetWeldingFinishing | - |
| Classic Machine & Engineering Milling, Turning, Laser, Welding, Grinding | Ashland, VA | MillingTurningLaserWeldingGrinding | - |
| Clinkenbeard & Associates Inc Milling, Casting, Assembly · AS9100, ITAR | South Beloit, IL | MillingCastingAssembly | AS9100, ITAR |
| Clow Stamping Company, Inc Milling, Turning, Laser, Bending, Welding, Stamping, EDM, Grinding, Finishing, Assembly | Merrifield, MN | MillingTurningLaserBendingWeldingStampingEDMGrindingFinishingAssembly | - |
| CM Manufacturing Inc Milling, Turning · ISO 9001, AS9100, ITAR | Missoula, MT | MillingTurning | ISO 9001, AS9100, ITAR |
| Columbus Machine Works Milling, Turning, Bending, Welding, EDM, Casting | Columbus, OH | MillingTurningBendingWeldingEDMCasting | - |
| Concise Manufacturing Inc Milling, Turning, Welding, EDM | Salisbury, NC | MillingTurningWeldingEDM | - |
| Conturo Prototyping, LLC Milling, Turning | Pittsburgh, PA | MillingTurning | - |
| Copen Machine, Inc Milling, Turning, Swiss, Welding, Grinding · ISO 9001 | Kent, OH | MillingTurningSwissWeldingGrinding | ISO 9001 |
| Criterion Precision Machining Milling, Turning · ISO 9001, AS9100 | Cleveland, OH | MillingTurning | ISO 9001, AS9100 |
| CS Tool Engineering, Inc Milling, Welding | Cedar Springs, MI | MillingWelding | - |
| Cte Machine Inc Milling, Turning, Finishing | Groveland, FL | MillingTurningFinishing | - |
| Custom Machine Milling, Turning, Welding, Grinding | Hagerstown, MD | MillingTurningWeldingGrinding | - |
| Custom Metalcraft Milling, Bending, Welding | Springfield, MO | MillingBendingWelding | - |
| Cutting Edge Manufacturing Milling, Turning, Assembly · ISO 9001, AS9100 | Newbury Park, CA | MillingTurningAssembly | ISO 9001, AS9100 |
| D & G Manufacturing LLC Milling, Turning, Welding | Aurora, CO | MillingTurningWelding | - |
| D. J. Fabricators, Inc Milling, Laser, Waterjet, Punching, Bending, Welding, EDM, Grinding, Assembly · ISO 9001 | Ipswich, MA | MillingLaserWaterjetPunchingBendingWeldingEDMGrindingAssembly | ISO 9001 |
| D&T Dynamics LLC Milling | Hyrum, UT | Milling | - |
| Daico Precision LLC Milling, Turning, Grinding, Finishing, Assembly | Garden Grove, CA | MillingTurningGrindingFinishingAssembly | - |
| Dark Threat Fabrication LLC Milling, Turning, Laser, Bending, Welding, Finishing · ISO 9001 | Heber Springs, AR | MillingTurningLaserBendingWeldingFinishing | ISO 9001 |
| Davis Tool & Die, Inc Milling, Turning, Welding, Stamping, EDM, Grinding | Abbeville, MS | MillingTurningWeldingStampingEDMGrinding | - |
| Decker Machine Works Inc Milling, Turning, Swiss, EDM, Grinding · ISO 9001, AS9100, ITAR | Greenfield, MA | MillingTurningSwissEDMGrinding | ISO 9001, AS9100, ITAR |
| Delflo Industries Inc Milling, Turning, Waterjet, Bending, Welding, EDM, Grinding, Assembly · ISO 9001, AS9100, ITAR, ISO 13485, CMMC | Delray Beach, FL | MillingTurningWaterjetBendingWeldingEDMGrindingAssembly | ISO 9001, AS9100, ITAR, ISO 13485, CMMC |
| Delta One Manufacturing LLC Milling, Turning, Laser, Welding, Finishing, Assembly | San Jose, CA | MillingTurningLaserWeldingFinishingAssembly | - |
| Desemco, LLC Milling, Turning, Laser · AS9100 | Marietta, GA | MillingTurningLaser | AS9100 |
| Dessureau Machines Inc Milling, Turning, Welding | Berlin, VT | MillingTurningWelding | - |
| Deval Life Cycle Support LLC Milling, Turning, Welding, Assembly · ISO 9001, AS9100 | Philadelphia, PA | MillingTurningWeldingAssembly | ISO 9001, AS9100 |
| Dexter Design & Development Co Milling, Turning, EDM, Grinding, Assembly · ISO 9001 | Hillsboro, OR | MillingTurningEDMGrindingAssembly | ISO 9001 |
| Dinucci Corp Milling, Turning · AS9100 | Concord, CA | MillingTurning | AS9100 |
| Diversified Machining Inc Milling, Welding | Forest Hill, MD | MillingWelding | - |
| DP Products, Inc Milling, Turning, EDM · ISO 9001 | San Jose, CA | MillingTurningEDM | ISO 9001 |
| Draeving Machine Tool, Inc Milling, Turning, Welding, EDM | Beloit, WI | MillingTurningWeldingEDM | - |
| DRM Industries Corp Milling, Turning, Laser, Welding, Casting · ISO 9001 | Lake Delton, WI | MillingTurningLaserWeldingCasting | ISO 9001 |
| DRP Machine Milling, Turning, Grinding · ISO 9001 | West Valley City, UT | MillingTurningGrinding | ISO 9001 |
| DT Precision, LLC Milling, Turning, Swiss · ISO 9001, AS9100, ITAR, ISO 13485 | San Jose, CA | MillingTurningSwiss | ISO 9001, AS9100, ITAR, ISO 13485 |
| Dynacut Manufacturing LLC Milling, Turning, Swiss, Finishing · ISO 9001 | Lees Summit, MO | MillingTurningSwissFinishing | ISO 9001 |
| Dynamic Balance Machine Milling, Turning · ISO 9001, AS9100, ITAR | Salt Lake City, UT | MillingTurning | ISO 9001, AS9100, ITAR |