| Warren Precision Milling, Turning, Swiss, Grinding | Warren, OH | MillingTurningSwissGrinding | - |
| Wichita Machine Products Inc Milling, Turning, Grinding, Assembly | Wichita, KS | MillingTurningGrindingAssembly | - |
| American Waterjet Cutting LLC Milling, Waterjet, Finishing | Winfield, IA | MillingWaterjetFinishing | - |
| Midway Swiss Turn, Inc Milling, Turning, Swiss, Finishing, Assembly · CMMC | Wooster, OH | MillingTurningSwissFinishingAssembly | CMMC |
| Moll Machine Works, LLC Milling, Turning, Welding | Williamson, NY | MillingTurningWelding | - |
| Super Web Digital, Inc Milling, Turning, Welding, Grinding | West Babylon, NY | MillingTurningWeldingGrinding | - |
| Two M Precision Co. Inc Milling, Grinding, Finishing · ISO 9001 | Willoughby, OH | MillingGrindingFinishing | ISO 9001 |
| US Tower Corp Milling, Welding, Assembly · ISO 9001 | Woodlake, CA | MillingWeldingAssembly | ISO 9001 |
| West Michigan Precision Machining Milling, Turning, Bending · ISO 9001, AS9100, ITAR | Walker, MI | MillingTurningBending | ISO 9001, AS9100, ITAR |
| Bowden Manufacturing Corp Milling, Turning, EDM · AS9100 | Willoughby, OH | MillingTurningEDM | AS9100 |
| Delaware Metals Milling, Turning, EDM | Wilmington, DE | MillingTurningEDM | - |
| Frey & Weiss Precision Machining Inc Milling, Turning, Grinding, Assembly · ISO 9001 | Wood Dale, IL | MillingTurningGrindingAssembly | ISO 9001 |
| Tidewater Machine Co Milling, Turning, EDM | White Plains, MD | MillingTurningEDM | - |
| Accuburn of Williamsport, Inc Milling, Laser, Bending, Welding, Assembly | Williamsport, IN | MillingLaserBendingWeldingAssembly | - |
| Digitrace Machine Works Ltd Milling, Welding, Stamping, Finishing | Wayland, MI | MillingWeldingStampingFinishing | - |
| Sinclair and Sons Custom Welding and Machining Service Inc Milling, Turning, Waterjet, Welding, Assembly · ISO 9001, AS9100, NADCAP | Wichita, KS | MillingTurningWaterjetWeldingAssembly | ISO 9001, AS9100, NADCAP |
| W & W Machine Co Inc Milling, Turning, Swiss, Welding, EDM, Finishing | Milford, CT | MillingTurningSwissWeldingEDMFinishing | - |
| W.C. Machine and Tool, Inc Milling, Waterjet, Punching, Welding, EDM, Grinding, Assembly | Chandler, AZ | MillingWaterjetPunchingWeldingEDMGrindingAssembly | - |
| Wagner Machine Company Milling, Turning, Swiss, Waterjet, Metal AM, EDM | Champaign, IL | MillingTurningSwissWaterjetMetal AMEDM | - |
| Wal-Tek Industries, Inc Milling, Turning, Laser, Welding, Finishing, Assembly · ISO 9001, AS9100, ITAR | Phoenix, AZ | MillingTurningLaserWeldingFinishingAssembly | ISO 9001, AS9100, ITAR |
| Walco Tool & Engineering Corp Milling, Turning, Welding, Grinding, Finishing · ISO 9001 | Romeoville, IL | MillingTurningWeldingGrindingFinishing | ISO 9001 |
| Walt Machine Inc Milling, Swiss, Welding | Lumberton, MS | MillingSwissWelding | - |
| Washington Machine Works Milling, Turning, Bending, Welding · ISO 9001 | Seattle, WA | MillingTurningBendingWelding | ISO 9001 |
| Wayne Integrated Technologies Corp Milling, Bending, Welding, Assembly · ISO 9001, AS9100 | Edgewood, NY | MillingBendingWeldingAssembly | ISO 9001, AS9100 |
| Weistec Engineering, Inc Milling, Turning, Laser, Waterjet, Bending, Welding · ISO 9001, AS9100, ITAR | Anaheim, CA | MillingTurningLaserWaterjetBendingWelding | ISO 9001, AS9100, ITAR |
| Weld Kraft Milling, Bending, Welding, Waterjet · ISO 9001 | St Louis Park, MN | MillingBendingWeldingWaterjet | ISO 9001 |
| Weldcraft Products Milling, Welding, Grinding | Tipp City, OH | MillingWeldingGrinding | - |
| Well Bilt Power Systems LLC Milling, Turning, Welding, Stamping | Union, NJ | MillingTurningWeldingStamping | - |
| Wells Technology, Inc Milling, Turning, Swiss, Finishing · ISO 9001, NADCAP, ISO 13485 | Bemidji, MN | MillingTurningSwissFinishing | ISO 9001, NADCAP, ISO 13485 |
| Wendtland Machine Works Milling, Turning, Laser, Welding | Sheridan, WY | MillingTurningLaserWelding | - |
| Werco Manufacturing Inc Milling, Turning, Laser, Bending, Welding, Finishing, Assembly · ISO 9001 | Broken Arrow, OK | MillingTurningLaserBendingWeldingFinishingAssembly | ISO 9001 |
| Wesco Machine Products, Inc Milling, Turning, Welding · ISO 9001 | Muskego, WI | MillingTurningWelding | ISO 9001 |
| Wess-Del Inc Milling, Waterjet, EDM, Assembly · ISO 9001, AS9100, ITAR, ISO 13485 | San Jose, CA | MillingWaterjetEDMAssembly | ISO 9001, AS9100, ITAR, ISO 13485 |
| West Cobb Engineering Milling, Waterjet, Welding, Assembly · ISO 9001, AS9100 | Douglasville, GA | MillingWaterjetWeldingAssembly | ISO 9001, AS9100 |
| West Engineering Co Inc Milling, Bending, Welding, EDM, Grinding, Assembly | Ashland, VA | MillingBendingWeldingEDMGrindingAssembly | - |
| West Palm Machining and Welding Milling, Turning, Waterjet, Welding | Riviera Beach, FL | MillingTurningWaterjetWelding | - |
| Western Industrial Machining Inc Milling, Laser, Welding, Assembly | Hampstead, MD | MillingLaserWeldingAssembly | - |
| Western Machine Works, LLC Milling, Welding | Portland, OR | MillingWelding | - |
| Western Metal Works Inc Milling, Waterjet, Welding | Albuquerque, NM | MillingWaterjetWelding | - |
| Western Precision Products Inc Milling, Turning, Swiss · AS9100 | Tualatin, OR | MillingTurningSwiss | AS9100 |
| Whalley Precision Inc Milling, Turning, Welding, Grinding, Finishing, Assembly · ISO 9001, ITAR, CMMC | Southwick, MA | MillingTurningWeldingGrindingFinishingAssembly | ISO 9001, ITAR, CMMC |
| Wheeler Industries Inc Milling, Turning, Bending, Welding | Spokane Valley, WA | MillingTurningBendingWelding | - |
| Whelan Machine & Tool, LLC Milling, Welding · ISO 9001, ITAR, CMMC | Louisville, KY | MillingWelding | ISO 9001, ITAR, CMMC |
| Whitmer Industries LLC Milling, Turning, Finishing · ISO 9001, ITAR | Baden, PA | MillingTurningFinishing | ISO 9001, ITAR |
| Wild Bore Machine, LLC Milling, Turning, Laser, Waterjet, Bending, Welding | East Dublin, GA | MillingTurningLaserWaterjetBendingWelding | - |
| Wildfactory Milling, Turning, Waterjet | Camarillo, CA | MillingTurningWaterjet | - |
| Williams Engineering LLC Milling, Turning, Welding | Cincinnati, OH | MillingTurningWelding | - |
| Wilson Precision Products LLC Milling, Welding, Grinding · ITAR | Temperance, MI | MillingWeldingGrinding | ITAR |
| Windmill Hill Manufacturing, LLC Milling, Turning, Waterjet, Welding, Grinding | Tully, NY | MillingTurningWaterjetWeldingGrinding | - |
| Wire Works EDM Inc Milling, Turning, Welding, EDM, Assembly · CMMC | Santa Ana, CA | MillingTurningWeldingEDMAssembly | CMMC |