| Meridian Industrial Group, LLC Milling, Turning, Welding, Casting · ISO 9001, AS9100 | Holyoke, MA | MillingTurningWeldingCasting | ISO 9001, AS9100 |
| Meridian Manufacturing Inc Milling, Turning, Laser, Welding, EDM, Grinding, Finishing | Ballston Spa, NY | MillingTurningLaserWeldingEDMGrindingFinishing | - |
| Mesatronics Inc Milling, Turning · ISO 9001, AS9100, ITAR, CMMC | Spicewood, TX | MillingTurning | ISO 9001, AS9100, ITAR, CMMC |
| Meta-Tech Industries, Inc Milling, Turning, Welding, EDM, Finishing · ISO 9001 | Houston, TX | MillingTurningWeldingEDMFinishing | ISO 9001 |
| Metal Essence Inc Milling, Turning, Swiss, Finishing, Assembly · ISO 9001, AS9100, ITAR | Longwood, FL | MillingTurningSwissFinishingAssembly | ISO 9001, AS9100, ITAR |
| Metal Fusion Inc Milling, Turning, Welding, Grinding | Redwood City, CA | MillingTurningWeldingGrinding | - |
| Metal Industries, Inc Milling, Turning, Welding | Hartford, CT | MillingTurningWelding | - |
| Metal Works Precision Machine and Tool, Inc Milling, Turning, Welding | Tucson, AZ | MillingTurningWelding | - |
| Metalcraft Inc Milling, Turning · AS9100 | Tempe, AZ | MillingTurning | AS9100 |
| Metalogic Industries LLC Milling, Turning, Swiss, Laser, Welding, EDM, Grinding | Southbridge, MA | MillingTurningSwissLaserWeldingEDMGrinding | - |
| Metalquest Unlimited, Inc Milling, Turning, Finishing, Assembly | Hebron, NE | MillingTurningFinishingAssembly | - |
| Metaltech CNC Machining LLC Milling, Turning, Bending | Portsmouth, RI | MillingTurningBending | - |
| Metro Machine Inc Milling, Turning, Grinding · ISO 9001, AS9100, ITAR | Englewood, CO | MillingTurningGrinding | ISO 9001, AS9100, ITAR |
| Metzger Machine Co. Milling, Turning, Welding | Cincinnati, OH | MillingTurningWelding | - |
| Meyer Tool & Manufacturing, Inc Milling, Turning, Welding · ITAR | Oak Lawn, IL | MillingTurningWelding | ITAR |
| Micar Fabrication Milling, Turning, Welding | Las Vegas, NV | MillingTurningWelding | - |
| Michigan CNC Tool, Inc Milling, Turning, EDM, Grinding · ISO 9001 | Whitmore Lake, MI | MillingTurningEDMGrinding | ISO 9001 |
| Micro Machine & Electronics, Inc Milling, Turning, Welding, Grinding, Finishing, Assembly · ITAR | Leominster, MA | MillingTurningWeldingGrindingFinishingAssembly | ITAR |
| Micron Applied Technologies, Inc Milling, Turning | Crosbyton, TX | MillingTurning | - |
| Micron Manufacturing Company Milling, Turning · ISO 9001 | Grand Rapids, MI | MillingTurning | ISO 9001 |
| Micron Precision Machining Inc Milling, Turning, EDM, Grinding | Saginaw, MI | MillingTurningEDMGrinding | - |
| Microwave Components Specialists, Inc Milling, Turning | Orleans, MA | MillingTurning | - |
| Middletown Industrial Technologies, LLC Milling, Turning, Welding, Stamping, Assembly | Middletown, OH | MillingTurningWeldingStampingAssembly | - |
| Midway Machine & Instrument Company Inc Milling, Turning, EDM, Finishing · ISO 9001 | South Houston, TX | MillingTurningEDMFinishing | ISO 9001 |
| Midway Swiss Turn, Inc Milling, Turning, Swiss, Finishing, Assembly · CMMC | Wooster, OH | MillingTurningSwissFinishingAssembly | CMMC |
| Midwest Tool Inc Milling, Turning, Welding, EDM, Grinding | Joplin, MO | MillingTurningWeldingEDMGrinding | - |
| Mikelson Machine Shop, Inc Milling, Turning | S El Monte, CA | MillingTurning | - |
| Mikron Manufacturing Inc Milling, Turning, Laser, Punching, Bending, Welding, Finishing, Assembly · ISO 9001, ITAR | Colorado Springs, CO | MillingTurningLaserPunchingBendingWeldingFinishingAssembly | ISO 9001, ITAR |
| Miller CNC Milling, Turning, Welding, Grinding · ISO 9001, AS9100 | Chula Vista, CA | MillingTurningWeldingGrinding | ISO 9001, AS9100 |
| Miller Diversified Machining Milling, Turning, Welding · ISO 9001, ITAR | Minneapolis, MN | MillingTurningWelding | ISO 9001, ITAR |
| Millrite Machine Inc Turning, Assembly · ISO 9001 | Westfield, MA | TurningAssembly | ISO 9001 |
| Mills Machine Works Inc Milling, Turning, Welding, Grinding | Lawrence, MA | MillingTurningWeldingGrinding | - |
| Millworx Precision Machining Inc Milling, Turning · ISO 9001, AS9100 | Corona, CA | MillingTurning | ISO 9001, AS9100 |
| Milo Engineering Milling, Turning, Grinding, Finishing · ISO 9001 | Torrance, CA | MillingTurningGrindingFinishing | ISO 9001 |
| Milton Manufacturing, Inc Turning, Bending, Welding, Stamping, Assembly · ITAR | Detroit, MI | TurningBendingWeldingStampingAssembly | ITAR |
| Milwaukee Bearing and Machining, Inc Milling, Turning · ISO 9001 | Menomonee Falls, WI | MillingTurning | ISO 9001 |
| Minic Precision, Inc Turning, Swiss · ISO 9001 | Spring Grove, IL | TurningSwiss | ISO 9001 |
| Models & Tools Inc Milling, Turning, Welding · AS9100 | Shelby Township, MI | MillingTurningWelding | AS9100 |
| Modern Machine Works Milling, Turning, Welding, EDM, Grinding, Finishing | Albany, OR | MillingTurningWeldingEDMGrindingFinishing | - |
| Moll Machine Works, LLC Milling, Turning, Welding | Williamson, NY | MillingTurningWelding | - |
| Monarch Valve Corp Milling, Turning, Welding, Grinding, Assembly · ISO 9001 | Aston, PA | MillingTurningWeldingGrindingAssembly | ISO 9001 |
| Mono Engineering Corp Turning, Welding, EDM · ISO 9001 | Chatsworth, CA | TurningWeldingEDM | ISO 9001 |
| Monsees Tool & Die Inc Milling, Turning, EDM, Grinding, Finishing | Rochester, NY | MillingTurningEDMGrindingFinishing | - |
| Montgomery Dynamics Milling, Turning, Welding · ISO 9001, ITAR | Huntingdon Valley, PA | MillingTurningWelding | ISO 9001, ITAR |
| Morehead Machinery Inc Milling, Turning, Welding, EDM, Grinding | Elkhart, IN | MillingTurningWeldingEDMGrinding | - |
| Morgan Bronze Products, Inc Turning, Welding, Casting · ISO 9001 | Lake Zurich, IL | TurningWeldingCasting | ISO 9001 |
| Moria Manufacturing LLC Milling, Turning, Finishing | Monona, WI | MillingTurningFinishing | - |
| Morrison Industries LLC Milling, Turning, Laser, Bending, Welding, Finishing, Assembly | Morrison, TN | MillingTurningLaserBendingWeldingFinishingAssembly | - |
| Motive Machine Works LLC Milling, Turning, Stamping, Finishing, Assembly | Lancaster, PA | MillingTurningStampingFinishingAssembly | - |
| Mountain CNC Milling, Turning, Waterjet, Welding, Grinding, Finishing, Assembly · ITAR, CMMC | Loveland, CO | MillingTurningWaterjetWeldingGrindingFinishingAssembly | ITAR, CMMC |