| Nolan's Machine Shop, Inc Milling, Turning, Welding, EDM, Grinding | Lafayette, LA | MillingTurningWeldingEDMGrinding | - |
| La Follette Machine & Tool Company, Inc Laser, Bending · ISO 9001 | La Follette, TN | LaserBending | ISO 9001 |
| Lakecity Industries Holding Inc Finishing | Lake City, PA | Finishing | - |
| Alliance Laser Inc Milling, Turning, Laser, Bending, Finishing | Slidell, LA | MillingTurningLaserBendingFinishing | - |
| Foxfab Laser and Machine Inc Milling, Laser, Bending, Welding, Grinding, Finishing | Layton, UT | MillingLaserBendingWeldingGrindingFinishing | - |
| 5G Modular MT, LLC Welding | Laurel, MT | Welding | - |
| Air-Lake Machine Milling, Turning, Welding | Lakeville, MN | MillingTurningWelding | - |
| Black Pearl Automation LLC Milling, Welding · AS9100, ITAR | Lascassas, TN | MillingWelding | AS9100, ITAR |
| Parallax Manufacturing LLC Milling, Turning, Bending, Welding, Stamping, Assembly · NADCAP | Lake Elsinore, CA | MillingTurningBendingWeldingStampingAssembly | NADCAP |
| Precision Tube Laser Milling, Laser, Bending, Welding | Las Vegas, NV | MillingLaserBendingWelding | - |
| Laguna Tools Turning, Laser, Waterjet | Grand Prairie, TX | TurningLaserWaterjet | - |
| Lai International Inc Milling, Laser, Waterjet, Welding, Metal AM, EDM, Finishing · NADCAP | Westminster, MD | MillingLaserWaterjetWeldingMetal AMEDMFinishing | NADCAP |
| Lakecraft, Inc Turning, Bending, Welding, Grinding, Finishing | Port Clinton, OH | TurningBendingWeldingGrindingFinishing | - |
| Lakehouse Industries Milling, Turning, Finishing | Woodland, WA | MillingTurningFinishing | - |
| Lakeside Innovative Technologies Milling, Turning, Finishing · ISO 9001, ITAR | Chittenango, NY | MillingTurningFinishing | ISO 9001, ITAR |
| Langley Industrial Machining Milling, Turning, Laser, Punching, Welding, Stamping, Finishing · ISO 9001 | Sharpsburg, NC | MillingTurningLaserPunchingWeldingStampingFinishing | ISO 9001 |
| Lanzen Inc Milling, Laser, Welding | Bruce Twp, MI | MillingLaserWelding | - |
| Larkin Precision, LLC Laser, Grinding | Kent, WA | LaserGrinding | - |
| Laser Craft Technologies Inc Milling, Turning, Laser, Punching, Bending, Welding, Assembly · ISO 9001 | Gainesville, GA | MillingTurningLaserPunchingBendingWeldingAssembly | ISO 9001 |
| Laser Cutting Co Milling, Laser, Bending, Welding, Grinding, Finishing · ISO 9001 | Harrison Township, MI | MillingLaserBendingWeldingGrindingFinishing | ISO 9001 |
| Laser Metal Fabrication Laser, Bending, Welding, Assembly | Twin Falls, ID | LaserBendingWeldingAssembly | - |
| Laserbend, LLC Laser, Bending, Welding, Finishing | Tujunga, CA | LaserBendingWeldingFinishing | - |
| Laserworx Mfg Laser, Bending, Welding, Stamping · AS9100, ITAR | Oxnard, CA | LaserBendingWeldingStamping | AS9100, ITAR |
| Latitude Corp Milling, Waterjet, Punching, Bending, Welding, Stamping, Grinding, Finishing · AS9100 | Verona, WI | MillingWaterjetPunchingBendingWeldingStampingGrindingFinishing | AS9100 |
| Latva Machine, LLC Milling, Turning, Stamping, Casting, Forging, Finishing · ISO 9001 | Newport, NH | MillingTurningStampingCastingForgingFinishing | ISO 9001 |
| Lavelle Medical LLC Milling, Turning, Laser, EDM, Finishing · ISO 9001, ITAR, ISO 13485 | Westford, MA | MillingTurningLaserEDMFinishing | ISO 9001, ITAR, ISO 13485 |
| Laystrom Manufacturing Company Bending, Laser, Welding | Chicago, IL | BendingLaserWelding | - |
| National Metal Stampings - Temecula Valley Milling, Turning, Welding, Stamping, EDM, Grinding · ISO 9001 | Lancaster, CA | MillingTurningWeldingStampingEDMGrinding | ISO 9001 |
| La Frenz Pattern Company, Incorporated Milling, Welding | Moline, IL | MillingWelding | - |
| La Gauge Co Milling, Turning, EDM, Grinding, Finishing · ISO 9001, AS9100, ITAR | Sun Valley, CA | MillingTurningEDMGrindingFinishing | ISO 9001, AS9100, ITAR |
| 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 | - |
| Lacross Enterprises Inc Turning, Laser, Punching, Bending, Welding | Louisville, KY | TurningLaserPunchingBendingWelding | - |
| Lad Engineering LLC Milling, Turning, EDM · ISO 9001, AS9100 | Albuquerque, NM | MillingTurningEDM | ISO 9001, AS9100 |
| Lake Precision Machine Inc Turning, Welding | Hagerstown, MD | TurningWelding | - |
| Lakes Area Manufacturing Co Milling, Grinding | Shafer, MN | MillingGrinding | - |
| Lakeview Forge Co Forging · ITAR | Erie, PA | Forging | ITAR |
| Lakota Industries Milling, Turning · AS9100, ITAR | Marysville, WA | MillingTurning | AS9100, ITAR |
| Lamjen Inc Milling, Turning, Welding, Stamping, Casting · ISO 9001 | Erie, PA | MillingTurningWeldingStampingCasting | ISO 9001 |
| Lange Grinding & Machining, Inc Milling, Turning, Welding, Grinding | Streetsboro, OH | MillingTurningWeldingGrinding | - |
| Langill's General Machine Inc Milling, Welding | Sacramento, CA | MillingWelding | - |
| Lark Industries Turning, Waterjet, Welding, Assembly · ISO 9001, ISO 13485 | El Paso, TX | TurningWaterjetWeldingAssembly | ISO 9001, ISO 13485 |
| Lasasco Inc Punching, Bending, Welding | Boise, ID | PunchingBendingWelding | - |
| Lathrom Manufacturing Inc Milling, Turning, Bending, Grinding · ISO 9001, ITAR | Wichita, KS | MillingTurningBendingGrinding | ISO 9001, ITAR |
| Lawrence Fabric & Metal Structures, Inc. Welding · ISO 9001 | St. Louis, MO | Welding | ISO 9001 |
| Lawruk Machine & Tool Milling, Turning, Welding, Grinding · ISO 9001 | Altoona, PA | MillingTurningWeldingGrinding | ISO 9001 |
| Lawson Precision Machining, Inc Milling, Turning, Welding, Grinding · ISO 9001 | Bucyrus, OH | MillingTurningWeldingGrinding | ISO 9001 |
| 865fablab Laser, Bending | Powell, TN | LaserBending | - |
| Advanced Plating Technologies Welding, Finishing · ISO 9001, ITAR, ISO 13485 | Milwaukee, WI | WeldingFinishing | ISO 9001, ITAR, ISO 13485 |
| Aerospace Laser Cleaning Welding, Grinding, Finishing · AS9100, ITAR, NADCAP | Monument, CO | WeldingGrindingFinishing | AS9100, ITAR, NADCAP |