| Caps Machine and Tool, LLC Milling, Turning | Ponder, TX | MillingTurning | - |
| Cardinal Metal Works LLC Welding, Assembly · ISO 9001 | Burgaw, NC | WeldingAssembly | ISO 9001 |
| Carley Foundry, Inc Casting · ISO 9001, NADCAP | Minneapolis, MN | Casting | ISO 9001, NADCAP |
| Carney Mfg LLC Milling | Beaumont, CA | Milling | - |
| Carr Machine & Tool, Inc Milling, Grinding, Assembly · ISO 9001, ITAR, CMMC | Elk Grove Village, IL | MillingGrindingAssembly | ISO 9001, ITAR, CMMC |
| Carver Machine Works Inc Waterjet, Welding, Assembly · ISO 9001, AS9100, NADCAP | Washington, NC | WaterjetWeldingAssembly | ISO 9001, AS9100, NADCAP |
| Carver Sheet Metal Works Inc Bending, Welding | Salt Lake City, UT | BendingWelding | - |
| Casco Machining Inc. Milling, Turning, Welding · ISO 9001 | San Jose, CA | MillingTurningWelding | ISO 9001 |
| Cassavant Machining, LLC Milling, Turning, Swiss, Welding, EDM, Grinding, Finishing · ISO 9001, AS9100 | Phoenix, AZ | MillingTurningSwissWeldingEDMGrindingFinishing | ISO 9001, AS9100 |
| CB Manufacturing & Engineering Inc Milling, Turning, EDM · ISO 9001, AS9100 | Santa Ana, CA | MillingTurningEDM | ISO 9001, AS9100 |
| CBM Fabrication Inc Milling, Turning, Waterjet, Welding, EDM, Grinding, Finishing | Ballston Lake, NY | MillingTurningWaterjetWeldingEDMGrindingFinishing | - |
| 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 |
| 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 | - |
| Century Tool Inc Milling, Welding, EDM, Grinding, Finishing, Assembly · ISO 9001 | Rogers, MN | MillingWeldingEDMGrindingFinishingAssembly | ISO 9001 |
| Certified Metal Finishing Welding, Casting, Finishing · ISO 9001, AS9100, NADCAP | Pompano Beach, FL | WeldingCastingFinishing | ISO 9001, AS9100, NADCAP |
| Chapco, Inc Laser, Punching, Bending, Welding, Grinding, Finishing, Assembly · ISO 9001, ITAR, CMMC | Deep River, CT | LaserPunchingBendingWeldingGrindingFinishingAssembly | ISO 9001, ITAR, CMMC |
| Chem Processing Inc Finishing · ISO 9001, AS9100, ITAR, NADCAP | Rockford, IL | Finishing | ISO 9001, AS9100, ITAR, NADCAP |
| Chicago CNC Machining Co. Milling, Turning, Bending, Welding | Hodgkins, IL | MillingTurningBendingWelding | - |
| Chicago Magnesium Casting Co Welding, Casting · AS9100, NADCAP | Blue Island, IL | WeldingCasting | AS9100, NADCAP |
| Chick Machine Company, LLC Milling, Turning, Waterjet, Grinding, Finishing · ISO 9001, AS9100, ITAR | Butler, PA | MillingTurningWaterjetGrindingFinishing | ISO 9001, AS9100, ITAR |
| Chromal Plating Co Grinding, Finishing | Los Angeles, CA | GrindingFinishing | - |
| CJ Precision Machine Inc Milling, Turning, Welding, Finishing · ISO 9001 | Boise, ID | MillingTurningWeldingFinishing | ISO 9001 |
| Cji Process Systems Inc Finishing | Santa Fe Springs, CA | Finishing | - |
| 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 |
| Class A Tooling Inc Milling, Turning, Bending, Welding, Stamping, EDM, Grinding | Cabot, AR | MillingTurningBendingWeldingStampingEDMGrinding | - |
| 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 | - |
| Clearshot Manufacturing LLC Milling, Swiss, Grinding, Finishing · ISO 9001 | Germantown, WI | MillingSwissGrindingFinishing | ISO 9001 |
| 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 | - |
| Cmmc Holdings, LLC Welding, Finishing · ISO 9001, CMMC | Sumter, SC | WeldingFinishing | ISO 9001, CMMC |
| 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 Machining & Engineering Inc Milling, Turning, Swiss | Ontario, CA | MillingTurningSwiss | - |
| CNC Manufacturing Inc Milling, Turning, Swiss, Laser, Grinding · ISO 9001 | Coatesville, PA | MillingTurningSwissLaserGrinding | ISO 9001 |
| CNCEdge Milling, Turning · ISO 9001 | Syracuse, NY | MillingTurning | ISO 9001 |
| Coastal Machine & Supply Inc Milling, Turning · ISO 9001, AS9100, ITAR, CMMC | Carencro, LA | MillingTurning | ISO 9001, AS9100, ITAR, CMMC |
| Coating Systems, Inc Finishing · NADCAP | Lowell, MA | Finishing | NADCAP |
| Coffeyville Sektam, Inc Milling, Turning, Welding, Grinding, Assembly | Coffeyville, KS | MillingTurningWeldingGrindingAssembly | - |
| Colbert Manufacturing Co Inc Milling, Turning, Welding, Grinding, Finishing | La Vergne, TN | MillingTurningWeldingGrindingFinishing | - |
| 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 Machine Works Welding, Grinding · CMMC | Portsmouth, VA | WeldingGrinding | CMMC |
| Colonial Welding, LLC Turning, Laser, Bending, Welding, Finishing | Norfolk, VA | TurningLaserBendingWeldingFinishing | - |