| CB Machining & Engineering Inc Milling, Turning, Swiss · ISO 9001, AS9100, ITAR | Buffalo, MN | MillingTurningSwiss | ISO 9001, AS9100, ITAR |
| CBM Fabrication Inc Milling, Turning, Waterjet, Welding, EDM, Grinding, Finishing | Ballston Lake, NY | MillingTurningWaterjetWeldingEDMGrindingFinishing | - |
| Cedar Industries, Inc Turning, Bending | Waterloo, IA | TurningBending | - |
| Celco, LLC Stamping, Finishing | Anthony, KS | StampingFinishing | - |
| Cellpoint Systems, Inc Stamping, Assembly | Fremont, CA | StampingAssembly | - |
| Center Tool Co Milling, Turning, Welding, Stamping, EDM, Grinding · ISO 9001 | Hampshire, IL | MillingTurningWeldingStampingEDMGrinding | ISO 9001 |
| Centerline Engineered Solutions, Inc Milling, Turning, Laser, Bending, Welding · ISO 9001 | Greenwood, SC | MillingTurningLaserBendingWelding | ISO 9001 |
| Centracore, LLC Casting · ISO 9001, IATF 16949 | Saint Clair, MI | Casting | ISO 9001, IATF 16949 |
| Central Valley Machine Inc Milling, Turning, Waterjet, Bending, Welding, EDM · AS9100, ITAR | Logan, UT | MillingTurningWaterjetBendingWeldingEDM | AS9100, ITAR |
| Century Metal Spinning Co Milling, Turning, Laser, Bending, Welding, Finishing · ISO 9001, AS9100, ITAR | Bensenville, IL | MillingTurningLaserBendingWeldingFinishing | ISO 9001, AS9100, ITAR |
| Century Tool Co Inc Milling, Turning, Welding, EDM, Grinding | Thompson, CT | MillingTurningWeldingEDMGrinding | - |
| Cerven Solutions, Inc Milling, Finishing · ISO 9001, AS9100, ITAR, CMMC | Arlington, NY | MillingFinishing | ISO 9001, AS9100, ITAR, CMMC |
| CES Machine Products Inc Milling, Turning · ISO 9001, AS9100, ITAR, ISO 13485 | Reno, NV | MillingTurning | ISO 9001, AS9100, ITAR, ISO 13485 |
| Chambers Welding & Fabrication Bending, Welding | Chattanooga, TN | BendingWelding | - |
| Chick Machine Company, LLC Milling, Turning, Waterjet, Grinding, Finishing · ISO 9001, AS9100, ITAR | Butler, PA | MillingTurningWaterjetGrindingFinishing | ISO 9001, AS9100, ITAR |
| Churchmen's Machine Company Milling, Turning, Laser, Waterjet, Welding, Grinding, Finishing | North East, MD | MillingTurningLaserWaterjetWeldingGrindingFinishing | - |
| Cimtech Inc Bending, Welding, Stamping | New Albany, IN | BendingWeldingStamping | - |
| Clardy Machine Works LLC Milling, Turning, Welding | Bremen, KY | MillingTurningWelding | - |
| Clark Fixture Technologies Inc Bending, Welding · ISO 9001, AS9100 | Bowling Green, OH | BendingWelding | ISO 9001, AS9100 |
| Clark Machine Corporation Welding, Finishing | Baltimore, MD | WeldingFinishing | - |
| Class Tool & Die Milling, Turning, Casting · ISO 9001 | Mukwonago, WI | MillingTurningCasting | ISO 9001 |
| Classic Engineering, LLC Milling, Turning, Waterjet, Welding, Finishing | Gloucester, MA | MillingTurningWaterjetWeldingFinishing | - |
| Classic Machine & Engineering Milling, Turning, Laser, Welding, Grinding | Ashland, VA | MillingTurningLaserWeldingGrinding | - |
| Classic Metal Finishing, Inc Milling, Swiss, Grinding, Finishing, Assembly · ISO 9001, AS9100, ITAR, NADCAP | Jackson, MI | MillingSwissGrindingFinishingAssembly | ISO 9001, AS9100, ITAR, NADCAP |
| Classic Turning Inc Milling, Turning, Swiss, Finishing | Jackson, MI | MillingTurningSwissFinishing | - |
| Clearshot Manufacturing LLC Milling, Swiss, Grinding, Finishing · ISO 9001 | Germantown, WI | MillingSwissGrindingFinishing | ISO 9001 |
| Cleveland Steel Services LLC Milling, Turning, Grinding | Middleburg Heights, OH | MillingTurningGrinding | - |
| Clinkenbeard & Associates Inc Milling, Casting, Assembly · AS9100, ITAR | South Beloit, IL | MillingCastingAssembly | AS9100, ITAR |
| CM Manufacturing Inc Milling, Turning · ISO 9001, AS9100, ITAR | Missoula, MT | MillingTurning | ISO 9001, AS9100, ITAR |
| CNC Innotech LLC Milling, Turning, Swiss | Ogdensburg, NJ | MillingTurningSwiss | - |
| CNC Machine and Fabrication, Inc Laser, Waterjet, Punching, Bending, Welding, Stamping, Grinding, Finishing | Hyde Park, UT | LaserWaterjetPunchingBendingWeldingStampingGrindingFinishing | - |
| CNC Specialties Manufacturing Inc Milling, Turning, Bending, Welding, EDM, Grinding, Finishing | Apollo, PA | MillingTurningBendingWeldingEDMGrindingFinishing | - |
| CNC Syndicate Welding | Ravenswood, WV | Welding | - |
| Coast Aerospace Manufacturing, Inc Milling, Welding · AS9100, ITAR | Placentia, CA | MillingWelding | AS9100, ITAR |
| Coast Metal Cutting Turning | San Jose, CA | Turning | - |
| Coastal Machine & Supply Inc Milling, Turning · ISO 9001, AS9100, ITAR, CMMC | Carencro, LA | MillingTurning | ISO 9001, AS9100, ITAR, CMMC |
| Cobalt Enterprises LLC Milling, Finishing · ITAR | Arlington, WA | MillingFinishing | ITAR |
| Colburn Manufacturing Company Milling, Turning · ISO 9001, ISO 13485 | Fridley, MN | MillingTurning | ISO 9001, ISO 13485 |
| Colleen & Herb Enterprises Inc Milling, Turning, Welding | Fremont, CA | MillingTurningWelding | - |
| Collins Custom Manufacturing LLC Milling · ISO 9001, ITAR | Fort Worth, TX | Milling | ISO 9001, ITAR |
| Collins Manufacturing Inc Milling, Turning, EDM · ITAR | Essex, MA | MillingTurningEDM | ITAR |
| Colonial Welding, LLC Turning, Laser, Bending, Welding, Finishing | Norfolk, VA | TurningLaserBendingWeldingFinishing | - |
| Colorado Machine Works, Inc. Milling, Turning | Colorado Springs, CO | MillingTurning | - |
| Columbia Machine Works, Inc Milling, Turning, Welding, Stamping, Casting · ISO 9001, ITAR | Columbia, TN | MillingTurningWeldingStampingCasting | ISO 9001, ITAR |
| Commercial Tool & Die Inc Milling, Turning, Welding, Grinding | Marshall, VA | MillingTurningWeldingGrinding | - |
| Compass Machine & Inspection LLC Milling | Houston, TX | Milling | - |
| Compatible Manufacturing, Inc Milling · ISO 9001, AS9100 | Marion, MT | Milling | ISO 9001, AS9100 |
| Competitive Engineering, Inc Milling, Turning, EDM, Grinding, Assembly · AS9100 | Tucson, AZ | MillingTurningEDMGrindingAssembly | AS9100 |
| Complex Fabricators, Inc. Bending, Laser, Welding, Stamping · AS9100 | Salt Lake City, UT | BendingLaserWeldingStamping | AS9100 |
| Concise Manufacturing Inc Milling, Turning, Welding, EDM | Salisbury, NC | MillingTurningWeldingEDM | - |