| KIKaba Ilco Corporation | Rocky Mount | NC | Primary Metal Manufacturing331420 | 100-499 | ● ACTIVE |
| KAKaiser Aluminum Alexco LLC | Chandler | AZ | Primary Metal Manufacturing331316 | 100-499 | ● ACTIVE |
Kaiser Aluminum Fabricated Products, LLC | Florence | AL | Primary Metal Manufacturing331318 | 20-99 | ● ACTIVE |
| KCKanthal Corporation | Bethel | CT | Primary Metal Manufacturing331221 | 20-99 | ● ACTIVE |
Karan and Associates, INC | Fontana | CA | Primary Metal Manufacturing331210 | — | ● ACTIVE |
| KCKawneer CO INC | Bloomsburg | PA | Primary Metal Manufacturing331318 | 100-499 | ● ACTIVE |
Kennametal INC | La Vergne | TN | Primary Metal Manufacturing331491 | 100-499 | ● ACTIVE |
| KCKeymark CORP of Florida | Lakeland | FL | Primary Metal Manufacturing331314 | 100-499 | ● ACTIVE |
| KCKingsbury Castings Division | Kingsbury | IN | Primary Metal Manufacturing331511 | 20-99 | ● ACTIVE |
Kittyhawk INC | Garden Grove | CA | Primary Metal Manufacturing331111 | 20-99 | ● ACTIVE |
Knoxville Sheet Metal Works, INC | Knoxville | TN | Primary Metal Manufacturing331315 | 20-99 | ● ACTIVE |
Kovatch Castings, INC | Uniontown | OH | Primary Metal Manufacturing331512 | 100-499 | ● ACTIVE |
| KIKreisler Industrial Corporation | Elmwood Park | NJ | Primary Metal Manufacturing331111 | 100-499 | ● ACTIVE |
Kuprion, INC. | San Jose | CA | Primary Metal Manufacturing331420 | 20-99 | ● ACTIVE |
Kutztown Foundry & Machine LLC | Kutztown | PA | Primary Metal Manufacturing331513 | 20-99 | ● ACTIVE |
Kvf-quad, Corporation | East Moline | IL | Primary Metal Manufacturing331221 | 20-99 | ● ACTIVE |
Kyocera Senco Industrial Tools, INC | Cincinnati | OH | Primary Metal Manufacturing331222 | 100-499 | ● ACTIVE |
| LMLangeloth Metallurgical Company LLC | Langeloth | PA | Primary Metal Manufacturing331110 | 20-99 | ● ACTIVE |
Latrobe Specialty Metals Co, LLC | Latrobe | PA | Chemical Manufacturing325311 | — | ● ACTIVE |
| LILeachgarner, INC. | Attleboro | MA | Primary Metal Manufacturing331491 | 100-499 | ● ACTIVE |
| LEL E Jones CO | Menominee | MI | Primary Metal Manufacturing331110 | 100-499 | ● ACTIVE |
Le Sueur, Incorporated | Le Sueur | MN | Primary Metal Manufacturing331523 | 100-499 | ● ACTIVE |
| LCLibertas Copper | Leetsdale | PA | Primary Metal Manufacturing331410 | 100-499 | ● ACTIVE |
Linear Motion LLC | Saginaw | MI | Primary Metal Manufacturing331111 | 100-499 | ● ACTIVE |
| LHLittlestown Hdwr & Foundry | Littlestown | PA | Primary Metal Manufacturing331524 | 20-99 | ● ACTIVE |
| LMLodge Manufacturing Company | South Pittsburg | TN | Primary Metal Manufacturing331511 | 500+ | ● ACTIVE |
Luvata Appleton LLC | Kimberly | WI | Primary Metal Manufacturing331420 | — | ● ACTIVE |
Madden Bolt Corporation | Houston | TX | Primary Metal Manufacturing331210 | 100-499 | ● ACTIVE |
Magellan Aerospace Glendale | Glendale | AZ | Primary Metal Manufacturing331523 | 100-499 | ● ACTIVE |
| MLMagpro, LLC | Camden | TN | Primary Metal Manufacturing331410 | 20-99 | ● ACTIVE |
| MEMahle Engine Components USA INC | Mcconnelsville | OH | Primary Metal Manufacturing331314 | 20-99 | ● ACTIVE |
Malin Company | Brookpark | OH | Primary Metal Manufacturing331222 | 20-99 | ● ACTIVE |
| MUMarmon Utility LLC | Seymour | CT | Primary Metal Manufacturing331491 | 100-499 | ● ACTIVE |
| MAMastermelt America LLC | Sweetwater | TN | Primary Metal Manufacturing331410 | 20-99 | ● ACTIVE |
| MIMatalco INC | Wisconsin Rapids | WI | Primary Metal Manufacturing331314 | 20-99 | ● ACTIVE |
| MBMaterion Brush INC | Elmore | OH | Primary Metal Manufacturing331410 | 500+ | ● ACTIVE |
Matthews International Corporation | Pittsburgh | PA | Primary Metal Manufacturing331523 | — | ● ACTIVE |
Maynard Steel Casting CO | Milwaukee | WI | Primary Metal Manufacturing331510 | 100-499 | ● ACTIVE |
| MDMcwane Ductile - New Jersey | Phillipsburg | NJ | Primary Metal Manufacturing331511 | 100-499 | ● ACTIVE |
M-d Building Products, INC. | Oklahoma City | OK | Primary Metal Manufacturing331318 | 500+ | ● ACTIVE |
| MEM E Global INC | Tempe | AZ | Primary Metal Manufacturing331513 | 100-499 | ● ACTIVE |
| MFMeloon Foundries, LLC | Syracuse | NY | Primary Metal Manufacturing331524 | 20-99 | ● ACTIVE |
| MSMerit Steel Company | Kouts | IN | Primary Metal Manufacturing331222 | 20-99 | ● ACTIVE |
| MRMetallic Resources INC | Twinsburg | OH | Primary Metal Manufacturing331491 | 20-99 | ● ACTIVE |
| MTMetal Technologies Auburn LLC | Auburn | IN | Primary Metal Manufacturing331511 | 100-499 | ● ACTIVE |
| MAMetalx Aluminum Conversions LLC | Wabash | IN | Primary Metal Manufacturing331314 | 100-499 | ● ACTIVE |
Metglas, INC | Conway | SC | Primary Metal Manufacturing331110 | 100-499 | ● ACTIVE |
| MSMichigan Seamless Tube, LLC | South Lyon | MI | Primary Metal Manufacturing331110 | 100-499 | ● ACTIVE |
Micro-tek Corporation | Cinnaminson | NJ | Primary Metal Manufacturing331491 | 20-99 | ● ACTIVE |
Miller Castings INC | Whittier | CA | Primary Metal Manufacturing331511 | 100-499 | ● ACTIVE |