| Metaltech CNC Machining LLC Milling, Turning, Bending | Portsmouth, RI | MillingTurningBending | - |
| Metaltech Inc Laser, Bending, Welding, Assembly · AS9100 | Auburn, WA | LaserBendingWeldingAssembly | AS9100 |
| MetalWork Austin Bending, Welding | Austin, TX | BendingWelding | - |
| Metalworking Group Bending, Welding · CMMC, ISO 9001, ITAR | Cincinnati, OH | BendingWelding | CMMC, ISO 9001, ITAR |
| Metco Metal Fab. Bending, Laser, Welding | Chattanooga, TN | BendingLaserWelding | - |
| Metplas Inc Milling, Turning, Waterjet, Punching, Bending, Assembly · ISO 9001 | Natrona Heights, PA | MillingTurningWaterjetPunchingBendingAssembly | ISO 9001 |
| MFC Netform LLC Milling, Laser, Waterjet, Bending, Welding, Stamping, Forging, EDM, Grinding · ISO 9001, IATF 16949 | Shelby Township, MI | MillingLaserWaterjetBendingWeldingStampingForgingEDMGrinding | ISO 9001, IATF 16949 |
| Micro Metals Inc Milling, Laser, Waterjet, Punching, Bending, Welding | Colorado Springs, CO | MillingLaserWaterjetPunchingBendingWelding | - |
| Microform Precision LLC Turning, Bending, Laser, Welding, Waterjet | Sacramento, CA | TurningBendingLaserWeldingWaterjet | - |
| Mid America Steel Inc Milling, Bending, Welding, Casting | Fargo, ND | MillingBendingWeldingCasting | - |
| Mid-Continent Engineering, LLC Bending, Welding, Grinding, Finishing · ISO 9001, AS9100, ITAR | Minneapolis, MN | BendingWeldingGrindingFinishing | ISO 9001, AS9100, ITAR |
| Mid-State Metals Bending, Welding | Orlando, FL | BendingWelding | - |
| Midlake Products & Mfg. Co., Inc Turning, Bending, Laser, Welding, Stamping | Canton, OH | TurningBendingLaserWeldingStamping | - |
| Midwest Industrial Metal Fabrication Inc Milling, Turning, Punching, Bending, Welding, Stamping, Finishing | Huntington, IN | MillingTurningPunchingBendingWeldingStampingFinishing | - |
| Midwest Metal Fabrications Milling, Turning, Bending, Laser, Welding · ISO 9001, AS9100 | Tallmadge, OH | MillingTurningBendingLaserWelding | ISO 9001, AS9100 |
| Midwest Tool Inc. Milling, Bending, Welding | Chicago, IL | MillingBendingWelding | - |
| Mikron Manufacturing Inc Milling, Turning, Laser, Punching, Bending, Welding, Finishing, Assembly · ISO 9001, ITAR | Colorado Springs, CO | MillingTurningLaserPunchingBendingWeldingFinishingAssembly | ISO 9001, ITAR |
| Millwood Metalworks Punching, Bending, Welding | Freeport, MN | PunchingBendingWelding | - |
| Milton Manufacturing, Inc Turning, Bending, Welding, Stamping, Assembly · ITAR | Detroit, MI | TurningBendingWeldingStampingAssembly | ITAR |
| Milwaukee Metal Products Co Bending, Welding, Stamping | Milwaukee, WI | BendingWeldingStamping | - |
| Mission Critical Solutions LLC Milling, Punching, Bending, Welding | Alum Bank, PA | MillingPunchingBendingWelding | - |
| MJM Manufacturing Inc Milling, Laser, Punching, Bending, Welding, Stamping · ISO 9001, AS9100, ITAR | Miami Lakes, FL | MillingLaserPunchingBendingWeldingStamping | ISO 9001, AS9100, ITAR |
| MM Industries Tech LLC Laser, Punching, Bending, Welding, Assembly | Stanwood, WA | LaserPunchingBendingWeldingAssembly | - |
| Modern Machine Milling, Turning, Bending, Welding, Stamping | Seattle, WA | MillingTurningBendingWeldingStamping | - |
| Mofab Inc Milling, Laser, Waterjet, Bending, Welding | Anderson, IN | MillingLaserWaterjetBendingWelding | - |
| Mojo Masters LLC Milling, Laser, Bending, EDM, Grinding | Vestal, NY | MillingLaserBendingEDMGrinding | - |
| Morrison Industries LLC Milling, Turning, Laser, Bending, Welding, Finishing, Assembly | Morrison, TN | MillingTurningLaserBendingWeldingFinishingAssembly | - |
| Motion Metalworks LLC Laser, Waterjet, Bending, Welding, Finishing | Wrens, GA | LaserWaterjetBendingWeldingFinishing | - |
| Moultrie Tool & Manufacturing Co Inc Milling, Turning, Bending, Welding, EDM, Stamping · ISO 9001 | Memphis, TN | MillingTurningBendingWeldingEDMStamping | ISO 9001 |
| Mountain Manufacturing, LLC Milling, Laser, Bending, Welding, Finishing, Assembly · ISO 13485 | Post Falls, ID | MillingLaserBendingWeldingFinishingAssembly | ISO 13485 |
| Mountain Precision Tool Co, Inc Milling, Turning, Laser, Waterjet, Punching, Bending, Welding, EDM, Grinding, Finishing | Blacksburg, VA | MillingTurningLaserWaterjetPunchingBendingWeldingEDMGrindingFinishing | - |
| Mountain Valley Machine, Inc Milling, Turning, Waterjet, Bending, Welding, EDM, Grinding · ISO 9001 | Smithfield, UT | MillingTurningWaterjetBendingWeldingEDMGrinding | ISO 9001 |
| MRW Fabrication LLC Bending, Welding | Independence, MO | BendingWelding | - |
| MSP Maufacturing Milling, Turning, Bending, Welding, Finishing, Assembly | Bloomington, IN | MillingTurningBendingWeldingFinishingAssembly | - |
| MST Manufacturing LLC Milling, Turning, Bending, Welding, Assembly · ISO 9001, AS9100, ITAR, CMMC | Claremore, OK | MillingTurningBendingWeldingAssembly | ISO 9001, AS9100, ITAR, CMMC |
| Mueller Machining LLC Milling, Turning, Laser, Bending, Grinding, Finishing | Salem, OR | MillingTurningLaserBendingGrindingFinishing | - |
| Music City Sheet Metal Bending, Laser, Welding | Nashville, TN | BendingLaserWelding | - |
| Nace Sheet Metal Co Bending, Laser, Welding | Anaheim, CA | BendingLaserWelding | - |
| Naimor Inc Milling, Turning, Laser, Punching, Bending, Welding, Finishing, Assembly | Snohomish, WA | MillingTurningLaserPunchingBendingWeldingFinishingAssembly | - |
| Napoleon Machine LLC Milling, Bending, Welding, Forging, Grinding · ISO 9001, ITAR, CMMC | Napoleon, OH | MillingBendingWeldingForgingGrinding | ISO 9001, ITAR, CMMC |
| Nashville Sheet Metal Bending, Welding | Nashville, TN | BendingWelding | - |
| Netzer Metalworks, LLC Milling, Punching, Bending, Welding, Finishing, Assembly · NADCAP | Essex, MD | MillingPunchingBendingWeldingFinishingAssembly | NADCAP |
| Nevada Precision Sheet Metal Milling, Bending, Laser, Welding, Waterjet | Las Vegas, NV | MillingBendingLaserWeldingWaterjet | - |
| New England Foundry LLC Milling, Bending, Welding, Stamping, Casting, EDM, Grinding, Finishing · ISO 9001 | Taunton, MA | MillingBendingWeldingStampingCastingEDMGrindingFinishing | ISO 9001 |
| New Method Steel Stamps Inc Milling, Turning, Laser, Bending, Stamping · ISO 9001 | Fraser, MI | MillingTurningLaserBendingStamping | ISO 9001 |
| New Tech Metals Milling, Turning, Laser, Punching, Bending, Welding, Stamping, Finishing, Assembly · ISO 9001, AS9100, ITAR, IATF 16949, CMMC | Green Bay, WI | MillingTurningLaserPunchingBendingWeldingStampingFinishingAssembly | ISO 9001, AS9100, ITAR, IATF 16949, CMMC |
| Niagara Frontier Custom Fabrication Bending, Welding | Buffalo, NY | BendingWelding | - |
| Niagara Manufacturing Co Milling, Turning, Bending, Welding | Erie, PA | MillingTurningBendingWelding | - |
| Nicholson Metal Fabricators Bending, Welding | Dallas, TX | BendingWelding | - |
| NMB Manufacturing LLC Milling, Turning, Bending, Welding | Bixby, OK | MillingTurningBendingWelding | - |