| NNNewport News Shipbuilding Oakland Industrial Oip | Newport News | VA | — | ◇ UNVERIFIED |
| NLNext Level Metal | Baldwin | IL | — | ◇ UNVERIFIED |
| NWNiermann Weeks Company, INC | Millersville | MD | — | ◇ UNVERIFIED |
| NMNolin Milling INC | Dickens | IA | — | ◇ UNVERIFIED |
| NMNorthern Metal Fab INC | Baldwin | WI | — | ◇ UNVERIFIED |
| NGNorthrop Grumman Ship Systems INC | Waggaman | LA | — | ◇ UNVERIFIED |
| NSNorthshore Steel INC | Two Harbors | MN | — | ◇ UNVERIFIED |
| NSNorth State Steel Incorporated | Greenville | NC | — | ◇ UNVERIFIED |
| NSNorthwest Steel Fab INC Deer Park | Deer Park | WA | — | ◇ UNVERIFIED |
| NINova Industries INC | San Leandro | CA | — | ◇ UNVERIFIED |
| OFOberlin Filter Company | Pewaukee | WI | — | ◇ UNVERIFIED |
| OCObie Construction, INC. | Eugene | OR | — | ◇ UNVERIFIED |
| OIOcci INC. Wwtp | Fulton | MO | — | ◇ UNVERIFIED |
| OSOcean Steel CORP | Conklin | NY | — | ◇ UNVERIFIED |
| OCOctober CO Chemetal Division | Easthampton | MA | — | ◇ UNVERIFIED |
| OFOem Fabricators INC | Neillsville | WI | — | ◇ UNVERIFIED |
| OCOglivie Company INC the | Astoria | OR | — | ◇ UNVERIFIED |
| OSOhio Steel Industries | Pataskala | OH | — | ◇ UNVERIFIED |
| OEOmega Engineering INC | Bridgeport | NJ | — | ◇ UNVERIFIED |
| ONOmega Natchiq New Iberia Facility | New Iberia | LA | — | ◇ UNVERIFIED |
| OSOne Source Systems LLC | Vicksburg | MS | — | ◇ UNVERIFIED |
| OSOrange State Steel Construction, INC | Pinellas Park | FL | — | ◇ UNVERIFIED |
| OOOrchid Orthopedics | Arcadia | CA | — | ◇ UNVERIFIED |
| OIOregon Iron Works Hidden Way | Vancouver | WA | — | ◇ UNVERIFIED |
| OIOregon Iron Works INC 3001 | Vancouver | WA | — | ◇ UNVERIFIED |
| OMOrion Marine Construction, INC | Tampa | FL | — | ◇ UNVERIFIED |
| OMOrnamental Metalworks INC | Decatur | IL | — | ◇ UNVERIFIED |
| OSOutland Steel, INC. | Caldwell | ID | — | ◇ UNVERIFIED |
| OSOzark Steel Fabricators INC | Farmington | MO | — | ◇ UNVERIFIED |
| PSPabrico Steel Fabricators | Paterson | NJ | — | ◇ UNVERIFIED |
| PIPacal Industries LLC | La Crosse | WI | — | ◇ UNVERIFIED |
| PWPampa Wind Tower Manufacturing Facility | Pampa | TX | — | ◇ UNVERIFIED |
| PPParton & Preble INC | Warren | MI | — | ◇ UNVERIFIED |
| PPPdm Precast | Carlisle | IA | — | ◇ UNVERIFIED |
| PMPelican Metal Products LLC | Harrison Township | MI | — | ◇ UNVERIFIED |
| PPPenz Products, INC. | Mishawaka | IN | — | ◇ UNVERIFIED |
| PAPerfect Air Control LLC / Metal Industries LLC of Nc | Marion | NC | — | ◇ UNVERIFIED |
| PEPerformance Energy Services LLC - Amelia Yard | Morgan City | LA | — | ◇ UNVERIFIED |
| PSPerformance Structures, INC. | Oakland | CA | — | ◇ UNVERIFIED |
| PNPermasteelisa North America | Harrison | NJ | — | ◇ UNVERIFIED |
| PMPetersen Metals | Hudson | FL | — | ◇ UNVERIFIED |
| PMPhilipp Mfg CO INC | Easthampton | MA | — | ◇ UNVERIFIED |
| PHP & H Mining Equipment | Milwaukee | WI | — | ◇ UNVERIFIED |
| PMPhoenix Manufacturing CO | Memphis | TN | — | ◇ UNVERIFIED |
| PMPhoenix Metalcraft | Phoenix | AZ | — | ◇ UNVERIFIED |
| PVPinson Valley Fabricators INC | Birmingham, Al | AL | — | ◇ UNVERIFIED |
| PAPioneer Aerospace CORP | Milton | FL | — | ◇ UNVERIFIED |
| PCPioneer Consolidated | North Oxford | MA | — | ◇ UNVERIFIED |
| PTPlaya Tool & Marine INC | Santa Ana | CA | — | ◇ UNVERIFIED |
| PSPneu-mech Systems Manufacturing INC | Statesville | NC | — | ◇ UNVERIFIED |
| PSPortersville Sales & Testing/portersville | Portersville | PA | — | ◇ UNVERIFIED |
| PWPorter Welding INC | Zanesville | OH | — | ◇ UNVERIFIED |
| PAPostle Aluminum (p0448) | Cassopolis | MI | — | ◇ UNVERIFIED |
| PBPrecision Build Solutions, LLC | Tampa | FL | — | ◇ UNVERIFIED |
| PHPrecision Heat Treating | Montebello | CA | — | ◇ UNVERIFIED |
| PIPreferred Industrial Coatings LLC | Houma | LA | — | ◇ UNVERIFIED |
| PPPremier Plant Services INC | Sapulpa | OK | — | ◇ UNVERIFIED |
| PCPrime Coatings INC | Amelia | LA | — | ◇ UNVERIFIED |
| PFProductivity Fabricators, INC. | Richmond | IN | — | ◇ UNVERIFIED |
| PFPro Fab Tech LLC | Azusa | CA | — | ◇ UNVERIFIED |
| PRProgress Rail Services CORP | Louisville | KY | — | ◇ UNVERIFIED |
| PCPurdy CO | Burnham | IL | — | ◇ UNVERIFIED |
| QPQsi Plant #2 | Dothan | AL | — | ◇ UNVERIFIED |
| QOQuality One Steel Design | Shelbyville | KY | — | ◇ UNVERIFIED |
| QFQuicksteel Fab INC | Johnston | IA | — | ◇ UNVERIFIED |
| QJQuincy Joist Company | Quincy | FL | — | ◇ UNVERIFIED |
| RMRam Machine Tooling INC | Picayune | MS | — | ◇ UNVERIFIED |
| RHRanch Hand Beeville | Beeville | TX | — | ◇ UNVERIFIED |
| RIRatliff Industries | Lumberton | TX | — | ◇ UNVERIFIED |
| RIRayes Inc, Dba Wheelchairs of Kansas | Hays | KS | — | ◇ UNVERIFIED |
| RIRaysteel INC | Albuquerque | NM | — | ◇ UNVERIFIED |
| RIRds Industrial INC | Cocoa | FL | — | ◇ UNVERIFIED |
| RCRecycle City INC | Clifton City | NJ | — | ◇ UNVERIFIED |
| RSRedi Services LLC - Metal Parts Coating | Platteville | CO | — | ◇ UNVERIFIED |
| RRenaissance | Roanoke | VA | — | ◇ UNVERIFIED |
| RSResteel Supply Company, INC. | Warwick | RI | — | ◇ UNVERIFIED |
| RSRichardson Steel INC | Spring Valley | CA | — | ◇ UNVERIFIED |
| RTRipon Truck Repair & Equipment, LLC | Pickett | WI | — | ◇ UNVERIFIED |
| RARippel Architectural Metals INC | Chicago | IL | — | ◇ UNVERIFIED |
| RRoadmaster | Portland | OR | — | ◇ UNVERIFIED |
| RSRoane Steel Corporation | Rockwood | TN | — | ◇ UNVERIFIED |
| RMRocky Mountain Metals INC | Raton | NM | — | ◇ UNVERIFIED |
| RMRocky Mountain Orthodontic, INC. | Denver | CO | — | ◇ UNVERIFIED |
| RIRohn Industries INC | Bessemer | AL | — | ◇ UNVERIFIED |
| RSRossin Steel INC | San Diego | CA | — | ◇ UNVERIFIED |
| RIRoura Iron Works INC | Holly Springs | MS | — | ◇ UNVERIFIED |
| RSRule Steel | Caldwell | ID | — | ◇ UNVERIFIED |
| RHRwe Holding CO | New Castle | PA | — | ◇ UNVERIFIED |
| SBSa Baxter LLC | Chester | NY | — | ◇ UNVERIFIED |
| SISabre Industries | Alvarado | TX | — | ◇ UNVERIFIED |
| SSSchmidt Structural Prod Inc/souderton | Souderton | PA | — | ◇ UNVERIFIED |
 Schuff Steel - Atlantic, INC. | Orlando | FL | — | ◇ UNVERIFIED |
| Schuff Steel Gulf Coast | Humble | TX | — | ◇ UNVERIFIED |
| SSeatech | Belle Chasse | LA | — | ◇ UNVERIFIED |
| SISemco Incorporated Chillicothe | Chillicothe | MO | — | ◇ UNVERIFIED |
| SMSeminole Machine & Welding, INC. | Largo | FL | — | ◇ UNVERIFIED |
| SMSentry Metal Blast INC | Niagara Falls | NY | — | ◇ UNVERIFIED |
| SIService Iron Works-s Lyon | South Lyon | MI | — | ◇ UNVERIFIED |
| SAShaw App Tubeline | New Brunswick | NJ | — | ◇ UNVERIFIED |
| SPShaw Process Fabricators | West Monroe | LA | — | ◇ UNVERIFIED |
