| B&K Machining LLC Milling, Turning, Welding | Centerville, IA | MillingTurningWelding | - |
| Baiar Industries Milling, Turning, Welding, EDM | Columbia Falls, MT | MillingTurningWeldingEDM | - |
| Baldwin Metals Inc Milling, Turning, Bending, Laser, Welding | Dallas, TX | MillingTurningBendingLaserWelding | - |
| Ball Industries LLC Milling, Turning, Grinding | Annville, KY | MillingTurningGrinding | - |
| Banks Engineering & Machine LLC Milling, Turning, Welding, Casting, Grinding · ISO 9001 | Webb City, MO | MillingTurningWeldingCastingGrinding | ISO 9001 |
| Banner Metalcraft Inc Milling, Turning, Laser, Punching, Bending, Welding, Stamping, Grinding, Finishing · AS9100 | Ronkonkoma, NY | MillingTurningLaserPunchingBendingWeldingStampingGrindingFinishing | AS9100 |
| Barnes Welding Inc Turning, Bending, Welding | Waterville, WA | TurningBendingWelding | - |
| Baron Machine Co., Inc. Milling, Turning, Welding · ISO 9001, AS9100, ITAR | Laconia, NH | MillingTurningWelding | ISO 9001, AS9100, ITAR |
| Bart's Machine Shop, Inc Milling, Turning | Morgan, UT | MillingTurning | - |
| Basin Precision Machining LLC Milling, Turning, Grinding · ISO 9001 | Jefferson, WI | MillingTurningGrinding | ISO 9001 |
| Baum Machine Inc Milling, Turning, Welding | Appleton, WI | MillingTurningWelding | - |
| Baum Precision Machining Inc Milling, Turning, Assembly · ISO 9001, AS9100, ITAR | Pipersville, PA | MillingTurningAssembly | ISO 9001, AS9100, ITAR |
| Bauman Machine Inc Milling, Turning, Laser, Welding · ISO 9001 | Oklahoma City, OK | MillingTurningLaserWelding | ISO 9001 |
| Bay State Machine Co Milling, Turning, Grinding, Assembly | Easthampton, MA | MillingTurningGrindingAssembly | - |
| Bear Machinery, Inc Milling, Turning, Waterjet, Bending, Welding, Grinding, Assembly · ISO 9001, ITAR | Kaneohe, HI | MillingTurningWaterjetBendingWeldingGrindingAssembly | ISO 9001, ITAR |
| Beatrice Machine, LLC Milling, Turning, Welding | Beatrice, NE | MillingTurningWelding | - |
| Bec Machine Products Milling, Turning, Welding, Casting | Harleysville, PA | MillingTurningWeldingCasting | - |
| Bedford Machine & Tool Inc Milling, Turning, Welding, Casting, Finishing | Bedford, IN | MillingTurningWeldingCastingFinishing | - |
| Beers Tooling and Machining Milling, Turning, Welding, Finishing · ISO 9001 | Jim Thorpe, PA | MillingTurningWeldingFinishing | ISO 9001 |
| Beistel Machining, Inc Milling, Turning · ISO 9001 | Donora, PA | MillingTurning | ISO 9001 |
| Belding Tool and Machine Milling, Turning, Welding, EDM, Grinding | Belding, MI | MillingTurningWeldingEDMGrinding | - |
| Belfanti Machine Works LLC Milling, Turning, Waterjet, Welding, Stamping | Beaverton, OR | MillingTurningWaterjetWeldingStamping | - |
| Bell Machine Co Inc Milling, Turning, Welding, Grinding · ISO 9001 | Shreveport, LA | MillingTurningWeldingGrinding | ISO 9001 |
| Beloit Precision, Inc Milling, Turning, Stamping · ISO 9001 | Beloit, WI | MillingTurningStamping | ISO 9001 |
| Bem CNC Milling, Turning | Schaumburg, IL | MillingTurning | - |
| Bender Precision Machining Incorporated Milling, Turning | Keyport, NJ | MillingTurning | - |
| Benen Manufacturing LLC Milling, Turning, Welding, Finishing, Assembly · ISO 9001, ISO 13485 | San Jose, CA | MillingTurningWeldingFinishingAssembly | ISO 9001, ISO 13485 |
| Bennett Metal Products Inc Milling, Turning, Waterjet, Welding · ISO 9001, ITAR | Mount Vernon, IL | MillingTurningWaterjetWelding | ISO 9001, ITAR |
| Benson Machine Works Inc. Turning, Bending, Laser, Welding | Omaha, NE | TurningBendingLaserWelding | - |
| Bent River Machine Inc Milling, Turning, Bending, Welding, EDM, Grinding, Finishing, Assembly · ISO 9001 | Clarkdale, AZ | MillingTurningBendingWeldingEDMGrindingFinishingAssembly | ISO 9001 |
| Bent River Tech Milling, Turning, EDM, Grinding | Vancouver, WA | MillingTurningEDMGrinding | - |
| Benton Machine Works Inc. Milling, Turning | Jacksonville, FL | MillingTurning | - |
| Beonca Machine Inc Milling, Turning · ISO 9001, AS9100, ITAR | La Verne, CA | MillingTurning | ISO 9001, AS9100, ITAR |
| Bergeron Machine LLC Turning, Swiss · ISO 9001 | Westford, MA | TurningSwiss | ISO 9001 |
| Bertrand Products, Inc Milling, Turning, Grinding, Finishing · ISO 9001 | South Bend, IN | MillingTurningGrindingFinishing | ISO 9001 |
| Best Machine Inc Milling, Turning, Swiss, Bending, Welding, EDM, Grinding · ISO 9001, ITAR | Fremont, NH | MillingTurningSwissBendingWeldingEDMGrinding | ISO 9001, ITAR |
| Betts Precision, Inc Milling, Turning, EDM, Grinding · AS9100, ISO 13485 | Alsip, IL | MillingTurningEDMGrinding | AS9100, ISO 13485 |
| Beyond Precision, LLC Milling, Turning · ISO 9001, AS9100 | Santa Ana, CA | MillingTurning | ISO 9001, AS9100 |
| Billet Industries Inc Milling, Turning, Laser, Welding, EDM, Grinding, Assembly · AS9100 | York, PA | MillingTurningLaserWeldingEDMGrindingAssembly | AS9100 |
| Bircher Inc Milling, Turning, Bending, Welding | Morehead City, NC | MillingTurningBendingWelding | - |
| Bishop Aviation Inc Milling, Turning, Bending, EDM · ISO 9001, AS9100, ITAR | Hot Springs National Park, AR | MillingTurningBendingEDM | ISO 9001, AS9100, ITAR |
| Blackburn's Fabrication Milling, Turning, Bending, Laser, Welding | Columbus, OH | MillingTurningBendingLaserWelding | - |
| Blackhawk Engineering LLC Milling, Turning · ISO 9001, ITAR | Cedar Falls, IA | MillingTurning | ISO 9001, ITAR |
| Blackhawk Machine Products Inc Milling, Turning | Smithfield, RI | MillingTurning | - |
| Blake Machine Milling, Turning, Welding | Phoenix, AZ | MillingTurningWelding | - |
| Bluewater Industries Inc Milling, Turning, Welding, Casting, Finishing | Moses Lake, WA | MillingTurningWeldingCastingFinishing | - |
| BMW Precision Machining Milling, Turning, Swiss · ITAR | Oceanside, CA | MillingTurningSwiss | ITAR |
| Bob Lewis Machine Company, Inc Milling, Turning, Welding, EDM, Grinding, Finishing · ISO 9001, AS9100 | Gardena, CA | MillingTurningWeldingEDMGrindingFinishing | ISO 9001, AS9100 |
| Bogue Machine Co Inc Milling, Turning, Bending, Welding, Waterjet, EDM · ISO 9001, AS9100, ITAR | Albuquerque, NM | MillingTurningBendingWeldingWaterjetEDM | ISO 9001, AS9100, ITAR |
| Boniface Tool & Die Inc Milling, Turning, Waterjet, Stamping, Grinding, Finishing | Dudley, MA | MillingTurningWaterjetStampingGrindingFinishing | - |