| Incremental Machine Milling, Bending | Baltimore, MD | MillingBending | - |
| Industrial Fabricators Milling, Turning, Bending, Welding, Waterjet | Corpus Christi, TX | MillingTurningBendingWeldingWaterjet | - |
| Industrial Sales & Manufacturing, Inc. Milling, Turning, Bending, Laser, Welding · ISO 9001 | Erie, PA | MillingTurningBendingLaserWelding | ISO 9001 |
| Innovated Metal Fabrication, Inc Turning, Bending, Laser, Welding | Maplewood, MN | TurningBendingLaserWelding | - |
| Innovation Alley Milling, Turning, Bending, Welding | Fresno, CA | MillingTurningBendingWelding | - |
| IntoMetal Bending, Laser, Welding, Metal AM | Lincoln, NE | BendingLaserWeldingMetal AM | - |
| IronStrong Metal Fabrication LLC Milling, Bending, Laser, Welding | Lancaster, PA | MillingBendingLaserWelding | - |
| J & L Sheet Metal Bending, Welding | Houston, TX | BendingWelding | - |
| J E Fifer Sheet Metal Fabricators Inc Bending, Laser, Welding | Richmond, VA | BendingLaserWelding | - |
| J.W. Steel Fabricating Co. Bending, Welding | Mars, PA | BendingWelding | - |
| Jaguar Precision Machine, LLC. Milling, Turning, Bending, Welding, Waterjet, Stamping, Metal AM · ISO 9001, AS9100, ITAR | Albuquerque, NM | MillingTurningBendingWeldingWaterjetStampingMetal AM | ISO 9001, AS9100, ITAR |
| Jax Precision Milling, Turning, Bending, Metal AM · ISO 9001, AS9100, ITAR | Jacksonville, FL | MillingTurningBendingMetal AM | ISO 9001, AS9100, ITAR |
| JD Machine Milling, Turning, Bending, Welding, EDM · ISO 9001, AS9100, ITAR, CMMC | Ogden, UT | MillingTurningBendingWeldingEDM | ISO 9001, AS9100, ITAR, CMMC |
| Jet Speed Metals Bending, Welding | Westbrook, ME | BendingWelding | - |
| John W. McDougall Co. Bending, Laser, Welding · ISO 9001 | Nashville, TN | BendingLaserWelding | ISO 9001 |
| Jones & Lockhart Fabrication LLC Bending, Welding | St. Louis, MO | BendingWelding | - |
| JP Metal Fabrication, Inc. Milling, Bending, Laser, Welding | Santa Clara, CA | MillingBendingLaserWelding | - |
| KBM Industries Bending, Welding | Mechanicsburg, PA | BendingWelding | - |
| Kenney Industries, Inc. Bending, Welding · ISO 9001, NADCAP | Dallas, TX | BendingWelding | ISO 9001, NADCAP |
| Kern Steel Fabrication Inc Bending, Welding · ISO 9001 | Bakersfield, CA | BendingWelding | ISO 9001 |
| King Tek EDM & Precision Machining Milling, Bending, Welding, EDM · ISO 9001, AS9100, ITAR, NADCAP | Anaheim, CA | MillingBendingWeldingEDM | ISO 9001, AS9100, ITAR, NADCAP |
| Kinney Manufacturing, LLC Bending, Laser, Welding, Metal AM | Lincoln, NE | BendingLaserWeldingMetal AM | - |
| La Machine Shop, Inc. Milling, Turning, Bending · ISO 9001, AS9100 | Ham Lake, MN | MillingTurningBending | ISO 9001, AS9100 |
| Laciny Brothers., Inc. Bending, Welding, Waterjet | St. Louis, MO | BendingWeldingWaterjet | - |
| Laystrom Manufacturing Company Bending, Laser, Welding | Chicago, IL | BendingLaserWelding | - |
| Lee Precision Machine Shop Inc. Milling, Turning, Bending, Welding, EDM · ISO 9001, ITAR | Athens, AL | MillingTurningBendingWeldingEDM | ISO 9001, ITAR |
| LJ Fabricators, Inc. Bending, Laser, Welding · ISO 9001 | Rockford, IL | BendingLaserWelding | ISO 9001 |
| Logan Machine Co Milling, Turning, Bending, Welding | Akron, OH | MillingTurningBendingWelding | - |
| Luna's Sheet Metal Inc Milling, Turning, Bending, Laser, Welding | Santa Clara, CA | MillingTurningBendingLaserWelding | - |
| M 7 Technologies Bending, Welding · ISO 9001 | Youngstown, OH | BendingWelding | ISO 9001 |
| M B Steel Milling, Bending, Laser, Welding, Stamping | St. Louis, MO | MillingBendingLaserWeldingStamping | - |
| M&M Metals Inc. Bending, Laser, Welding | San Antonio, TX | BendingLaserWelding | - |
| Mac-Tech Turning, Bending, Laser, Welding | Milwaukee, WI | TurningBendingLaserWelding | - |
| Machine Time Inc Milling, Turning, Bending, Welding · ISO 9001, AS9100 | Nicholasville, KY | MillingTurningBendingWelding | ISO 9001, AS9100 |
| Machine Tool Services Turning, Bending, EDM | Spokane, WA | TurningBendingEDM | - |
| Majestic Metals by Fathom Manufacturing Milling, Turning, Bending, Laser, Welding, Waterjet, EDM, Casting, Metal AM · ISO 9001, AS9100, ITAR, ISO 13485 | Denver, CO | MillingTurningBendingLaserWeldingWaterjetEDMCastingMetal AM | ISO 9001, AS9100, ITAR, ISO 13485 |
| Make + SHift atx Bending | Austin, TX | Bending | - |
| Maria Custom Sheet Metal Bending, Welding | Englewood, CO | BendingWelding | - |
| Mark One Metal Works Turning, Bending, Welding | Sparks, NV | TurningBendingWelding | - |
| Master Machine, Inc Milling, Turning, Bending, Casting · ISO 9001 | Minneapolis, MN | MillingTurningBendingCasting | ISO 9001 |
| Master Metal Products Co Bending, Welding | San Jose, CA | BendingWelding | - |
| McAlpin Industries Inc. Milling, Bending, Laser, Welding, Stamping | Rochester, NY | MillingBendingLaserWeldingStamping | - |
| McKenna Metal Bending, Laser, Welding, Waterjet | Portland, OR | BendingLaserWeldingWaterjet | - |
| Mecha Inc Milling, Bending, Welding, Waterjet · ISO 9001, ITAR, NADCAP | Raleigh, NC | MillingBendingWeldingWaterjet | ISO 9001, ITAR, NADCAP |
| Megla Manufacturing, Inc. Milling, Bending, Laser, Welding, Waterjet | National City, CA | MillingBendingLaserWeldingWaterjet | - |
| Melton Sheet Metal Bending, Welding | Fresno, CA | BendingWelding | - |
| Merritt Welding & Fabrication Bending, Welding | Denver, CO | BendingWelding | - |
| Metal Line Bending, Welding | Salt Lake City, UT | BendingWelding | - |
| Metal Pro, Inc. Milling, Bending, Welding | Phoenix, AZ | MillingBendingWelding | - |
| Metalcraft Creative Bending, Laser, Welding | Birmingham, AL | BendingLaserWelding | - |