| Iq Manufacturing LLC Milling, Stamping, EDM, Grinding · ISO 9001 | Auburn Hills, MI | MillingStampingEDMGrinding | ISO 9001 |
| Ironbound Castings II, LLC Milling, Turning, Casting | Newark, NJ | MillingTurningCasting | - |
| IronStrong Metal Fabrication LLC Milling, Bending, Laser, Welding | Lancaster, PA | MillingBendingLaserWelding | - |
| Isembard Corporation Milling, Turning · ISO 9001, AS9100, ITAR, CMMC | Carrollton, TX | MillingTurning | ISO 9001, AS9100, ITAR, CMMC |
| J & L Precision Manufacturing LLC Bending, Welding, Stamping, Finishing, Assembly · ISO 9001 | Brooklyn Heights, OH | BendingWeldingStampingFinishingAssembly | ISO 9001 |
| J & N Metal Products, LLC Milling, Laser, Bending, Welding, EDM · ISO 9001 | Brazil, IN | MillingLaserBendingWeldingEDM | ISO 9001 |
| J A-Co Machine Works, LLC Milling, Turning, Swiss, Welding, Finishing, Assembly · ISO 9001, AS9100, ITAR, NADCAP, ISO 13485 | Scotts Valley, CA | MillingTurningSwissWeldingFinishingAssembly | ISO 9001, AS9100, ITAR, NADCAP, ISO 13485 |
| J E Fifer Sheet Metal Fabricators Inc Bending, Laser, Welding | Richmond, VA | BendingLaserWelding | - |
| J Newell Corp Milling, Welding | Arlington, WA | MillingWelding | - |
| J P Corporation Milling, Turning · ISO 9001, AS9100 | Beech Grove, IN | MillingTurning | ISO 9001, AS9100 |
| J W Machine & Fab LLC Milling, Turning, Welding, Grinding | Fountain Inn, SC | MillingTurningWeldingGrinding | - |
| J. I. Machine Co., Inc Milling, Turning, Swiss · ISO 9001, AS9100, ITAR | San Diego, CA | MillingTurningSwiss | ISO 9001, AS9100, ITAR |
| J. L. Machine, LLC Milling, Turning | Zebulon, NC | MillingTurning | - |
| J.B. Anderson & Son, Inc Milling, Turning, Welding, Assembly | Irwin, PA | MillingTurningWeldingAssembly | - |
| J.i.t. Manufacturing, Inc Milling, Laser, Punching, Bending, Welding, Finishing, Assembly | Cowpens, SC | MillingLaserPunchingBendingWeldingFinishingAssembly | - |
| J&D Custom Finishing | Holden, MO | Finishing | - |
| J&M Machining Milling, Turning, Welding, Casting, Finishing · ISO 9001 | Norton Shores, MI | MillingTurningWeldingCastingFinishing | ISO 9001 |
| Jacksonville Machine, Inc Milling, Turning, Welding, Grinding · ISO 9001 | Jacksonville, IL | MillingTurningWeldingGrinding | ISO 9001 |
| Jaco Engineering Milling, Turning, Bending, Welding, EDM, Grinding, Finishing, Assembly · NADCAP | Anaheim, CA | MillingTurningBendingWeldingEDMGrindingFinishingAssembly | NADCAP |
| Jaffa Precision Engineering Inc Milling, Turning, Swiss, Welding, Grinding, Finishing · ISO 9001 | Riverside, CA | MillingTurningSwissWeldingGrindingFinishing | ISO 9001 |
| Jars Inc Milling, Waterjet, Bending, Welding, EDM, Grinding, Finishing | San Fernando, CA | MillingWaterjetBendingWeldingEDMGrindingFinishing | - |
| Jarvis Manufacturing, Inc Milling, Turning, EDM, Assembly · ISO 9001, ITAR | San Jose, CA | MillingTurningEDMAssembly | ISO 9001, ITAR |
| Jax Fab Shop LLC Welding | Jacksonville, FL | Welding | - |
| Jax Laser Solutions LLC Laser | Jacksonville, FL | Laser | - |
| Jax Precision Milling, Turning, Bending, Metal AM · ISO 9001, AS9100, ITAR | Jacksonville, FL | MillingTurningBendingMetal AM | ISO 9001, AS9100, ITAR |
| JB Precision Machining, Inc Milling, Turning | Brentwood, NY | MillingTurning | - |
| JBC Machine Inc Milling, Turning, Welding, Finishing | Hortonville, WI | MillingTurningWeldingFinishing | - |
| JC Custom Machining & Design Inc Milling, Turning, Welding, Grinding | Hillsboro, OR | MillingTurningWeldingGrinding | - |
| JC Macelroy Co Inc Milling, Punching, Bending, Welding, Grinding, Assembly | Piscataway, NJ | MillingPunchingBendingWeldingGrindingAssembly | - |
| JC Machine, Inc Milling, Turning, Swiss, Laser, Bending, Welding | Lakeland, FL | MillingTurningSwissLaserBendingWelding | - |
| JD Machine Milling, Turning, Bending, Welding, EDM · ISO 9001, AS9100, ITAR, CMMC | Ogden, UT | MillingTurningBendingWeldingEDM | ISO 9001, AS9100, ITAR, CMMC |
| Jeglinski Group Inc Milling, Turning, Welding, EDM, Grinding, Assembly · ISO 9001 | Meadville, PA | MillingTurningWeldingEDMGrindingAssembly | ISO 9001 |
| Jem Custom Products, Inc Milling, Finishing | Wauconda, IL | MillingFinishing | - |
| Jenkins Machine Inc Milling, Turning, EDM, Grinding, Finishing | Bethlehem, PA | MillingTurningEDMGrindingFinishing | - |
| Jep Manufacturing LLC Milling, Turning, Welding · ISO 9001 | Rosenberg, TX | MillingTurningWelding | ISO 9001 |
| Jerry's Welding & Machine Welding | San Diego, CA | Welding | - |
| Jet Helseth Manufacturing Inc Turning, EDM, Finishing, Assembly · ISO 9001, ITAR | Deland, FL | TurningEDMFinishingAssembly | ISO 9001, ITAR |
| Jet Machine & Mfg Milling, Welding | Hamilton, OH | MillingWelding | - |
| Jet Machined Products, LLC Milling, Turning, Stamping, Grinding · ISO 9001, ITAR | East Bridgewater, MA | MillingTurningStampingGrinding | ISO 9001, ITAR |
| Jet Speed Metals Bending, Welding | Westbrook, ME | BendingWelding | - |
| Jetfab LLC Milling, Turning, Laser, Waterjet, Punching, Bending, Welding | Lowell, MA | MillingTurningLaserWaterjetPunchingBendingWelding | - |
| Jewett Machine Milling, Turning, Welding · ISO 9001 | Richmond, VA | MillingTurningWelding | ISO 9001 |
| JG Innovations, Inc Finishing | Janesville, WI | Finishing | - |
| JJR Engineering & Fabrication Inc Milling, Turning, Bending, Welding, Stamping, Finishing, Assembly · ISO 9001, AS9100, NADCAP | Woodinville, WA | MillingTurningBendingWeldingStampingFinishingAssembly | ISO 9001, AS9100, NADCAP |
| JK Pulley Co Inc Milling, Turning, Welding | Saint Louis, MO | MillingTurningWelding | - |
| Jkeys LLC Laser, Bending, Finishing | Willis, TX | LaserBendingFinishing | - |
| JMR Machining LLC Milling, Turning, Casting, Finishing | Athens, TX | MillingTurningCastingFinishing | - |
| Joels Machine Shop Inc Milling, Turning, Grinding | El Monte, CA | MillingTurningGrinding | - |
| John J Steuby Co Milling, Turning, Swiss, Welding, Stamping, Casting, EDM, Finishing · ISO 9001, ITAR | Hazelwood, MO | MillingTurningSwissWeldingStampingCastingEDMFinishing | ISO 9001, ITAR |
| John W. McDougall Co. Bending, Laser, Welding · ISO 9001 | Nashville, TN | BendingLaserWelding | ISO 9001 |