| Critical Defense Inc Milling, Turning, Bending, Welding, Grinding, Assembly | Windber, PA | MillingTurningBendingWeldingGrindingAssembly | - |
| Custom Engineering Co Milling, Turning, Bending, Welding · ISO 9001, ITAR, NADCAP | Erie, PA | MillingTurningBendingWelding | ISO 9001, ITAR, NADCAP |
| Custom Laser Works LLC Laser, Bending, Welding | Addison, IL | LaserBendingWelding | - |
| Custom Manufacturing Co Bending, Laser, Welding, Stamping · ISO 9001 | Dallas, TX | BendingLaserWeldingStamping | ISO 9001 |
| Custom Metal Fabricators Milling, Bending, Laser, Welding | Richmond, VA | MillingBendingLaserWelding | - |
| Custom Metal Works Milling, Bending, Welding | Tulsa, OK | MillingBendingWelding | - |
| Custom Metalcraft Milling, Bending, Welding | Springfield, MO | MillingBendingWelding | - |
| Cutting Edge Fabrication Inc Milling, Bending, Laser, Welding · ISO 9001 | Milwaukee, WI | MillingBendingLaserWelding | ISO 9001 |
| Cutting Solutions Turning, Laser, Waterjet, Bending, Welding, Grinding, Finishing, Assembly | Zeeland, MI | TurningLaserWaterjetBendingWeldingGrindingFinishingAssembly | - |
| D & D Design & Manufacturing Inc Milling, Turning, Bending, Laser, Welding | Oklahoma City, OK | MillingTurningBendingLaserWelding | - |
| D & G Machine Products, LLC Milling, Turning, Bending, Laser, Welding · ISO 9001, AS9100 | Gorham, ME | MillingTurningBendingLaserWelding | ISO 9001, AS9100 |
| D & H Industries Inc Milling, Turning, Laser, Bending, Welding, Stamping, Grinding, Finishing · ISO 9001, ITAR | Oconomowoc, WI | MillingTurningLaserBendingWeldingStampingGrindingFinishing | ISO 9001, ITAR |
| D. J. Fabricators, Inc Milling, Laser, Waterjet, Punching, Bending, Welding, EDM, Grinding, Assembly · ISO 9001 | Ipswich, MA | MillingLaserWaterjetPunchingBendingWeldingEDMGrindingAssembly | ISO 9001 |
| DAD Manufacturing, Inc. Bending, Welding · ISO 9001 | Hiawatha, IA | BendingWelding | ISO 9001 |
| Dallas Precision Machining Milling, Turning, Bending, Laser, Welding, Waterjet, Metal AM · ISO 9001, AS9100, ITAR | Carrollton, TX | MillingTurningBendingLaserWeldingWaterjetMetal AM | ISO 9001, AS9100, ITAR |
| Danser, Inc Milling, Laser, Punching, Bending, Welding | Davisville, WV | MillingLaserPunchingBendingWelding | - |
| Dark Threat Fabrication LLC Milling, Turning, Laser, Bending, Welding, Finishing · ISO 9001 | Heber Springs, AR | MillingTurningLaserBendingWeldingFinishing | ISO 9001 |
| Denali MetalWorks Bending, Laser, Welding, Waterjet | Phoenix, AZ | BendingLaserWeldingWaterjet | - |
| Deperini Metal Fabricators Milling, Laser, Punching, Bending, Welding, Grinding, Finishing · ISO 9001 | Gaithersburg, MD | MillingLaserPunchingBendingWeldingGrindingFinishing | ISO 9001 |
| Des Moines Iron & Supply Co Bending, Welding | Des Moines, IA | BendingWelding | - |
| Des Moines Metal Fab Bending, Laser, Welding | Des Moines, IA | BendingLaserWelding | - |
| Desert Metal Works Bending, Laser, Welding, Waterjet | Tucson, AZ | BendingLaserWeldingWaterjet | - |
| Desert Precision Manufacturing Bending, Laser, Welding · ISO 9001 | Tucson, AZ | BendingLaserWelding | ISO 9001 |
| Design Metal, Inc Milling, Turning, Bending, Welding, Stamping · ISO 9001 | Oak Park, MI | MillingTurningBendingWeldingStamping | ISO 9001 |
| DGF Industrial Innovations Group, Ltd Milling, Turning, Bending, Welding · ISO 9001 | Gilford, NH | MillingTurningBendingWelding | ISO 9001 |
| Die-Cut Products Co Bending, Laser, Welding, Waterjet, EDM, Stamping | Cleveland, OH | BendingLaserWeldingWaterjetEDMStamping | - |
| Diverse Metal Products Bending, Laser, Welding, Stamping · ISO 9001 | Houston, TX | BendingLaserWeldingStamping | ISO 9001 |
| Donahue Industries, Incorporated Milling, Turning, Swiss, Punching, Bending, Welding, Stamping, EDM, Grinding, Finishing | Shrewsbury, MA | MillingTurningSwissPunchingBendingWeldingStampingEDMGrindingFinishing | - |
| Douglas Machine & Engineering Milling, Turning, Bending, Welding, EDM · ISO 9001, AS9100, ITAR, CMMC | Davenport, IA | MillingTurningBendingWeldingEDM | ISO 9001, AS9100, ITAR, CMMC |
| DW Products Milling, Turning, Bending, Welding, Waterjet · ISO 9001, ITAR | Cedar Rapids, IA | MillingTurningBendingWeldingWaterjet | ISO 9001, ITAR |
| Dynamic Design & Manufacturing Inc Laser, Punching, Bending, Welding, EDM · ISO 9001, AS9100, ITAR | Niwot, CO | LaserPunchingBendingWeldingEDM | ISO 9001, AS9100, ITAR |
| Dynamic Metal Innovations LLC Laser, Bending, Welding, Finishing, Assembly · ITAR | Emmaus, PA | LaserBendingWeldingFinishingAssembly | ITAR |
| Dynamic Sheetmetal Fabrication, LLC Bending, Welding · ISO 9001 | St Paul, MN | BendingWelding | ISO 9001 |
| E-Sector Machining and Fabrication LLC Milling, Turning, Laser, Bending, Welding, EDM, Grinding · ISO 9001 | Sanford, FL | MillingTurningLaserBendingWeldingEDMGrinding | ISO 9001 |
| E.H. Schwab Milling, Turning, Laser, Punching, Bending, Welding · ISO 9001 | Turtle Creek, PA | MillingTurningLaserPunchingBendingWelding | ISO 9001 |
| Eagle Metalcraft Bending, Laser, Welding, Metal AM · ISO 9001, ITAR | East Syracuse, NY | BendingLaserWeldingMetal AM | ISO 9001, ITAR |
| Eberl Iron Works, Inc. Bending, Welding | Buffalo, NY | BendingWelding | - |
| Eck Fabrication LLC Milling, Turning, Bending, Welding, Grinding | Kingman, KS | MillingTurningBendingWeldingGrinding | - |
| Edco Engineering Inc Milling, Bending, Welding · ISO 9001, AS9100, NADCAP | Newington, CT | MillingBendingWelding | ISO 9001, AS9100, NADCAP |
| Edker Industries LLC Milling, Turning, Laser, Punching, Bending, Welding, Finishing, Assembly | Bala Cynwyd, PA | MillingTurningLaserPunchingBendingWeldingFinishingAssembly | - |
| eMachineShop Milling, Turning, Bending, Laser, Welding, Waterjet, Stamping, Metal AM · ITAR | Mahwah, NJ | MillingTurningBendingLaserWeldingWaterjetStampingMetal AM | ITAR |
| Emb Machining Services Inc Milling, Turning, Bending, Welding, Grinding, Assembly · ISO 9001, ITAR | Whitney, PA | MillingTurningBendingWeldingGrindingAssembly | ISO 9001, ITAR |
| Empire Metal Products Turning, Bending, Welding | Phoenix, AZ | TurningBendingWelding | - |
| En.Zo Metal Milling, Bending, Laser, Welding, Waterjet | Brooklyn, NY | MillingBendingLaserWeldingWaterjet | - |
| Engineered Fabrication, Inc Milling, Turning, Laser, Waterjet, Bending, Welding, Finishing · ISO 9001 | Watkinsville, GA | MillingTurningLaserWaterjetBendingWeldingFinishing | ISO 9001 |
| Engineered Mechanical Systems Inc Milling, Turning, Laser, Bending, Welding | Chattanooga, TN | MillingTurningLaserBendingWelding | - |
| Espas Inc Laser, Bending, Welding, Stamping, Assembly · ISO 9001 | Clinton Township, MI | LaserBendingWeldingStampingAssembly | ISO 9001 |
| Estes Design & Manufacturing Inc Milling, Turning, Laser, Punching, Bending, Welding, Grinding · ISO 13485 | Indianapolis, IN | MillingTurningLaserPunchingBendingWeldingGrinding | ISO 13485 |
| Evans Metal Fabricators Inc Milling, Turning, Bending, Laser, Welding | Portland, OR | MillingTurningBendingLaserWelding | - |
| Evansville Sheet Metal Works Bending, Laser, Welding, Waterjet | Evansville, IN | BendingLaserWeldingWaterjet | - |