| KAKalispell Art Foundry | Kalispell | MT | Primary Metal Manufacturing331528 | 1-19 | ◇ UNVERIFIED |
| AAsarco | Helena | MT | Primary Metal Manufacturing331410 | — | ◇ UNVERIFIED |
| BIBest in Bronze INC | Kalispell | MT | Primary Metal Manufacturing331525 | — | ◇ UNVERIFIED |
| CIChovanak INC | Helena | MT | Primary Metal Manufacturing331492 | — | ◇ UNVERIFIED |
| CFColumbia Falls Aluminum | Columbia Falls | MT | Primary Metal Manufacturing331312 | — | ◇ UNVERIFIED |
| CFColumbia Falls Aluminum Company Building 1 | Columbia Falls | MT | Primary Metal Manufacturing331313 | — | ◇ UNVERIFIED |
| NANorthwest Art Casting INC | Bozeman | MT | Primary Metal Manufacturing331525 | — | ◇ UNVERIFIED |
 Truenorth Steel | Billings | MT | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| UAUS Antimony CORP | Thompson Falls | MT | Primary Metal Manufacturing331410 | — | ◇ UNVERIFIED |
| ACArt Casting of Montana, INC. | Belgrade | MT | Primary Metal Manufacturing331513 | 1-19 | ◇ UNVERIFIED |
| CSContinental Steel Works, INC. | Butte | MT | Primary Metal Manufacturing331221 | — | ◇ UNVERIFIED |
| ABAti Bozeman INC | Bozeman | MT | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| CIClark Industrial INC. | Missoula | MT | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| CPColumbus Processing Facility | Columbus | MT | Primary Metal Manufacturing331419 | — | ◇ UNVERIFIED |
| CMContact Mining Company | Philipsburg | MT | Primary Metal Manufacturing331410 | — | ◇ UNVERIFIED |
| CICustom Ii Metal Fabrication and Welding | Bozeman | MT | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| JMJohnson Metal Works LLC | Bozeman | MT | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| KHKozba Holdings LLC | Billings | MT | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| NSNorthwest Short Line, LLC | Hamilton | MT | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| SMStillwater Mining Company | Columbus | MT | Primary Metal Manufacturing331419 | — | ◇ UNVERIFIED |
| SMStillwater Mining CO Smelter | Columbus | MT | Primary Metal Manufacturing331410 | — | ◇ UNVERIFIED |
| UAUS Antimony CORP | Thompson Falls | MT | Primary Metal Manufacturing331419 | — | ◇ UNVERIFIED |
