| KPKalas Plant 2 - K2 | Denver | PA | Primary Metal Manufacturing331420 | 100-499 | ◐ LIKELY ACTIVE |
| LOLatrobe Operations | Latrobe | PA | Primary Metal Manufacturing331110 | 100-499 | ◐ LIKELY ACTIVE |
| LMLoucks Mill | York | PA | Primary Metal Manufacturing331222 | 20-99 | ◐ LIKELY ACTIVE |
| LLLSM - Latrobe | Latrobe | PA | Primary Metal Manufacturing331110 | 500+ | ◐ LIKELY ACTIVE |
| LSLSM - Sandy Creek | Franklin | PA | Primary Metal Manufacturing331110 | 20-99 | ◐ LIKELY ACTIVE |
| LMLuxfer MEL Technologies - Tamaqua | Tamaqua | PA | Primary Metal Manufacturing331492 | 20-99 | ◐ LIKELY ACTIVE |
| MBMaster Builders & Erectors CORP | Folcroft | PA | Primary Metal Manufacturing331221 | — | ◐ LIKELY ACTIVE |
| MSMaterion - Shoemakersville | Shoemakersville | PA | Primary Metal Manufacturing331420 | 100-499 | ◐ LIKELY ACTIVE |
Matthews International Corporation - Pittsburgh Bronze | Pittsburgh | PA | Primary Metal Manufacturing331529 | 100-499 | ◐ LIKELY ACTIVE |
| MMetalac | Latrobe | PA | Primary Metal Manufacturing331110 | 1-19 | ◐ LIKELY ACTIVE |
| MPMetallurgical Products Company | West Chester | PA | Primary Metal Manufacturing331420 | 1-19 | ◐ LIKELY ACTIVE |
| MOMidland Operations | Midland | PA | Primary Metal Manufacturing331221 | 1-19 | ◐ LIKELY ACTIVE |
| MJMount Joy Wire Corporation | Mount Joy | PA | Primary Metal Manufacturing331222 | 100-499 | ◐ LIKELY ACTIVE |
| NSNelson Steel Products Inc. | Hatfield | PA | Primary Metal Manufacturing331222 | 20-99 | ◐ LIKELY ACTIVE |
| NWNelson Wire & Steel | New Salem | PA | Primary Metal Manufacturing331222 | 20-99 | ◐ LIKELY ACTIVE |
| NINF&M International, Inc. | Monaca | PA | Primary Metal Manufacturing331491 | 1-19 | ◐ LIKELY ACTIVE |
| NANORTH AMERICAN STAINLESS-Wrightsville | Whrightsville | PA | Primary Metal Manufacturing331221 | 1-19 | ◐ LIKELY ACTIVE |
| NSNucor Skyline | Camp Hill | PA | Primary Metal Manufacturing331221 | 20-99 | ◐ LIKELY ACTIVE |
| NInVent ILSCO | Greenville | PA | Primary Metal Manufacturing331318 | 20-99 | ◐ LIKELY ACTIVE |
| OLOci LLC | Brookville | PA | Primary Metal Manufacturing331210 | 100-499 | ◐ LIKELY ACTIVE |
| OIONI Industries | Ambridge | PA | Primary Metal Manufacturing331110 | 100-499 | ◐ LIKELY ACTIVE |
| OOPTA-Affival | New Kensington | PA | Primary Metal Manufacturing331110 | 20-99 | ◐ LIKELY ACTIVE |
| OTOPTA-Edgar Thomson | Braddock | PA | Primary Metal Manufacturing331110 | 1-19 | ◐ LIKELY ACTIVE |
| PAPennex Aluminum Company - Greenville | Greenville | PA | Primary Metal Manufacturing331314 | 20-99 | ◐ LIKELY ACTIVE |
| PCPerma Cast | Export | PA | Primary Metal Manufacturing331529 | 20-99 | ◐ LIKELY ACTIVE |
| PCPerryman Company Melt Shop | Coal Center | PA | Primary Metal Manufacturing331491 | 100-499 | ◐ LIKELY ACTIVE |
| PFPerryman Frackville Operations | Frackville | PA | Primary Metal Manufacturing331491 | 1-19 | ◐ LIKELY ACTIVE |
| PTPerryman Ti Conversion | Houston | PA | Primary Metal Manufacturing331491 | 100-499 | ◐ LIKELY ACTIVE |
| PSPittsburgh Service Center | Pittsburgh | PA | Primary Metal Manufacturing331110 | 100-499 | ◐ LIKELY ACTIVE |
| PMPrime Metals Acquisition, LLC | Homer City | PA | Primary Metal Manufacturing331110 | 20-99 | ◐ LIKELY ACTIVE |
| PMP.t.i. Machine, Incorporated | Delta | PA | Primary Metal Manufacturing331210 | — | ◐ LIKELY ACTIVE |
| QAQ Aluminum LLC | New Berlin | PA | Primary Metal Manufacturing331524 | 1-19 | ◐ LIKELY ACTIVE |
| RAResearch and Technology Center | Munhall | PA | Primary Metal Manufacturing331110 | 100-499 | ◐ LIKELY ACTIVE |
| RRResources Recycling Management LLC | Fairless Hills | PA | Primary Metal Manufacturing331492 | 1-19 | ◐ LIKELY ACTIVE |
| RORochester Operations | Rochester | PA | Primary Metal Manufacturing331221 | 1-19 | ◐ LIKELY ACTIVE |
| SSSibanye Stillwater Reldan - PA | Fairless Hills | PA | Primary Metal Manufacturing331492 | 100-499 | ◐ LIKELY ACTIVE |
Superior Forge & Steel New Castle | New Castle | PA | Primary Metal Manufacturing331513 | 20-99 | ◐ LIKELY ACTIVE |
| SKSwagelok Koppel | Koppel | PA | Primary Metal Manufacturing331210 | 20-99 | ◐ LIKELY ACTIVE |
| TTidewood | Tamaqua PA | PA | Primary Metal Manufacturing331314 | 20-99 | ◐ LIKELY ACTIVE |
| TTIMET-Morgantown | Morgantown | PA | Primary Metal Manufacturing331492 | 100-499 | ◐ LIKELY ACTIVE |
| UCUnicast Company | Boyertown | PA | Primary Metal Manufacturing331511 | 20-99 | ◐ LIKELY ACTIVE |
| UEUnion Electric Steel- Carnegie Plant | Carnegie | PA | Primary Metal Manufacturing331110 | 100-499 | ◐ LIKELY ACTIVE |
| UEUnion Electric Steel- Harmon Creek Plant | Burgettstown | PA | Primary Metal Manufacturing331110 | 100-499 | ◐ LIKELY ACTIVE |
| VOVandergrift Operations | Vandergrift | PA | Primary Metal Manufacturing331221 | 100-499 | ◐ LIKELY ACTIVE |
Viant Collegeville LLC | Collegeville | PA | Primary Metal Manufacturing331210 | 100-499 | ◐ LIKELY ACTIVE |
| WOWashington Operations | Washington | PA | Primary Metal Manufacturing331221 | 100-499 | ◐ LIKELY ACTIVE |
| WVWebco VAF | Reno | PA | Primary Metal Manufacturing331210 | 20-99 | ◐ LIKELY ACTIVE |
| WSWelding Shops | Grindstone | PA | Primary Metal Manufacturing331110 | 1-19 | ◐ LIKELY ACTIVE |
| WEWestinghouse Electric Company - Specialty Metals Plant | Blairsville | PA | Primary Metal Manufacturing331491 | 100-499 | ◐ LIKELY ACTIVE |
| WCWhemco-steel Castings, INC | Pittsburgh | PA | Primary Metal Manufacturing331513 | — | ◐ LIKELY ACTIVE |