| Blue Arc Metal Specialties, Inc Bending, Welding, Finishing | Claremore, OK | BendingWeldingFinishing | - |
| Blue Ridge Machine Works Inc Milling, Turning, Waterjet, Welding, Grinding, Finishing | Verona, VA | MillingTurningWaterjetWeldingGrindingFinishing | - |
| Bmi Cad Services, Inc Milling, Turning, Welding, EDM, Grinding | Simsbury, CT | MillingTurningWeldingEDMGrinding | - |
| bo-mar Industries Bending, Welding, Waterjet | Indianapolis, IN | BendingWeldingWaterjet | - |
| Boise Metal Works Welding, Waterjet | Boise, ID | WeldingWaterjet | - |
| Bothe Associates Inc Milling, Turning, Swiss, Stamping · ISO 9001 | Kenosha, WI | MillingTurningSwissStamping | ISO 9001 |
| Boulevard Machine & Gear, Inc Milling, Turning, Grinding · ISO 9001, AS9100, ITAR | Westfield, MA | MillingTurningGrinding | ISO 9001, AS9100, ITAR |
| Bowden Manufacturing Corp Milling, Turning, EDM · AS9100 | Willoughby, OH | MillingTurningEDM | AS9100 |
| Boyce Machine Milling, Turning, Welding | Kent, OH | MillingTurningWelding | - |
| Boyer Machine & Tool Co Inc Milling, Turning, Swiss, EDM · ITAR | Columbus, IN | MillingTurningSwissEDM | ITAR |
| Brace Manufacturing Milling, Bending, Welding, Assembly | Garland, TX | MillingBendingWeldingAssembly | - |
| Bradhart Products, Inc Milling, Turning, Finishing · ISO 9001, ITAR | Brighton, MI | MillingTurningFinishing | ISO 9001, ITAR |
| Brenk Brothers Inc Milling, Turning, EDM, Grinding | Minneapolis, MN | MillingTurningEDMGrinding | - |
| Brennan Machine Co., Inc Milling · ISO 9001 | Hanson, MA | Milling | ISO 9001 |
| Bridan Mfg Inc Milling, Turning, EDM · ISO 9001 | Kenosha, WI | MillingTurningEDM | ISO 9001 |
| Bridesburg Foundry Company Casting | Whitehall, PA | Casting | - |
| Brinker Machine LLC Milling, Turning, Bending, Welding | Letart, WV | MillingTurningBendingWelding | - |
| Britech Electropolishing Inc Welding, Finishing | Newark, CA | WeldingFinishing | - |
| Broadway Metal Works Inc Milling, Turning, Laser, Waterjet, Bending, Welding | Broadway, VA | MillingTurningLaserWaterjetBendingWelding | - |
| Bronco Manufacturing Inc Milling, Turning, Assembly · ISO 9001, ITAR | Anna, TX | MillingTurningAssembly | ISO 9001, ITAR |
| Bront Machining Inc. Milling, Turning, Welding · ISO 9001, AS9100 | Dayton, OH | MillingTurningWelding | ISO 9001, AS9100 |
| Brown Industries Inc Milling, Turning, Bending, Welding | Kansas City, MO | MillingTurningBendingWelding | - |
| Brown Precision Inc Milling, Turning, Bending, Welding, Waterjet, EDM · ISO 9001, AS9100 | Huntsville, AL | MillingTurningBendingWeldingWaterjetEDM | ISO 9001, AS9100 |
| Bru Tek LLC Milling, Turning, Laser, Welding | Shelby Township, MI | MillingTurningLaserWelding | - |
| Buckeye Metal Works, Inc Laser, Welding, Waterjet | Columbus, OH | LaserWeldingWaterjet | - |
| Bula Forge & Machine Inc Milling, Turning, Welding, Forging, Assembly · ISO 9001 | Cleveland, OH | MillingTurningWeldingForgingAssembly | ISO 9001 |
| Burke Precision Machine Company, Incorporated Milling, Turning, Grinding · ISO 9001 | East Granby, CT | MillingTurningGrinding | ISO 9001 |
| Burnet Machining Inc Milling, Turning | Goleta, CA | MillingTurning | - |
| Burns Machine Co Milling, Turning, Bending, Welding, Grinding, Assembly · ISO 9001 | Ottawa, IL | MillingTurningBendingWeldingGrindingAssembly | ISO 9001 |
| Butler Precision Technologies LLC Milling, Turning, Welding, Finishing · AS9100, ITAR | Bristol, PA | MillingTurningWeldingFinishing | AS9100, ITAR |
| C & F Tool & Die Milling, Turning, Welding · ISO 9001, AS9100, ITAR | San Antonio, TX | MillingTurningWelding | ISO 9001, AS9100, ITAR |
| C & P Machine Welding | Fort Wayne, IN | Welding | - |
| C & S Machine Products Inc Milling, Turning, Swiss, EDM, Grinding · AS9100, NADCAP, ISO 13485 | Niles, MI | MillingTurningSwissEDMGrinding | AS9100, NADCAP, ISO 13485 |
| C P Precision Inc Milling, Finishing | Warminster, PA | MillingFinishing | - |
| C.E. Machine Company, Inc. Milling, Waterjet, Metal AM · ISO 9001, AS9100 | Wichita, KS | MillingWaterjetMetal AM | ISO 9001, AS9100 |
| C2 Machining Milling, Welding · ITAR | Kentwood, MI | MillingWelding | ITAR |
| Cal Machine & Manufacturing LLC Milling, Turning, Welding, Assembly · ISO 9001, AS9100 | Chino, CA | MillingTurningWeldingAssembly | ISO 9001, AS9100 |
| Caldwell Corp Milling, Turning, Welding, Grinding | Emporium, PA | MillingTurningWeldingGrinding | - |
| Calidad, Inc Casting · ISO 9001, AS9100, ITAR | Ontario, CA | Casting | ISO 9001, AS9100, ITAR |
| California Lasers Inc Milling, Laser, Welding, EDM, Grinding | Simi Valley, CA | MillingLaserWeldingEDMGrinding | - |
| CalWest MFG Milling, Turning, Laser, Waterjet, Bending, Welding · ISO 9001, ITAR | Fontana, CA | MillingTurningLaserWaterjetBendingWelding | ISO 9001, ITAR |
| Camcraft Inc Milling, Turning, Grinding | Hanover Park, IL | MillingTurningGrinding | - |
| Capital Industries Inc Laser, Punching, Bending, Welding, Finishing · ISO 9001 | Seattle, WA | LaserPunchingBendingWeldingFinishing | ISO 9001 |
| Carlisle Machine Works Inc Milling, Turning, Bending, Welding, EDM, Grinding | Millville, NJ | MillingTurningBendingWeldingEDMGrinding | - |
| Carlson Metal Products Inc Punching, Bending, Welding, Finishing, Assembly | Troy, MI | PunchingBendingWeldingFinishingAssembly | - |
| Carlson Tool & Manufacturing Corp Milling, Turning, EDM, Grinding | Cedarburg, WI | MillingTurningEDMGrinding | - |
| Carney Mfg LLC Milling | Beaumont, CA | Milling | - |
| Caron Precision Inc Turning · ISO 9001 | Kalamazoo, MI | Turning | ISO 9001 |
| Carver Machine Works Inc Waterjet, Welding, Assembly · ISO 9001, AS9100, NADCAP | Washington, NC | WaterjetWeldingAssembly | ISO 9001, AS9100, NADCAP |
| Cat-Wood Metalworks Milling, Turning, Assembly · ISO 9001, ITAR | Moraine, OH | MillingTurningAssembly | ISO 9001, ITAR |