| HLHeavy Line Fabrication | Anna | TX | — | ◇ UNVERIFIED |
| HMHeavy Metal Corporation | Cranston | RI | — | ◇ UNVERIFIED |
| HMHeavy Metal Fabrication | Colorado Springs | CO | — | ◇ UNVERIFIED |
| HSHeavy Stone Rings LLC | Orem | UT | — | ◇ UNVERIFIED |
| HMHec Manufacturing, INC. | Bardstown | KY | — | ◇ UNVERIFIED |
| HSHeintz Steel and Manufacturing Company | Saint Louis | MO | — | ◇ UNVERIFIED |
| HIHelser Industries of Nc | Sharpsburg | NC | — | ◇ UNVERIFIED |
| HFHenderson Fabrication | San Antonio | TX | — | ◇ UNVERIFIED |
| HWHenderson Welding, INC. | Chicago | IL | — | ◇ UNVERIFIED |
| HAHenry and Sons Construction | New Braunfels | TX | — | ◇ UNVERIFIED |
| HSHercules Steel Company, Incorporated | Richlands | NC | — | ◇ UNVERIFIED |
| HWHercules Wrought Iron Works INC | Chantilly | VA | — | ◇ UNVERIFIED |
| HCHeritage Custom Fabricators | Princeton | IN | — | ◇ UNVERIFIED |
| HBHerman Binz & Sons Iron Works | Little Rock | AR | — | ◇ UNVERIFIED |
| HSHerman Steel Inc | Slatington | PA | — | ◇ UNVERIFIED |
| HSHermitage Steel, Incorporated | Richmond | VA | — | ◇ UNVERIFIED |
| HWHernandez Wrought Iron, INC. | Ontario | CA | — | ◇ UNVERIFIED |
| HMHerndon & Merry INC | Nashville | TN | — | ◇ UNVERIFIED |
| HFHerrera Fabricating INC. | Houston | TX | — | ◇ UNVERIFIED |
| HCHerrick CORP Dba San Bernardino Steel INC | San Bernardino | CA | — | ◇ UNVERIFIED |
| HMHG Metals | Indianapolis | IN | — | ◇ UNVERIFIED |
| HHH Hirschberger CO INC | Portland | OR | — | ◇ UNVERIFIED |
| HIHigh Industries INC | Lancaster | PA | — | ◇ UNVERIFIED |
| HOHighland Ornamental Ironworks INC | Berryville | VA | — | ◇ UNVERIFIED |
| HSHighway Systems, INC. | Ocala | FL | — | ◇ UNVERIFIED |
| HIHiler's Ironworks LLC | Cave Junction | OR | — | ◇ UNVERIFIED |
| HRHill Rebar INC | Corona | CA | — | ◇ UNVERIFIED |
| HCHillside Custom Machining & Fabrication, LLC | Denver | PA | — | ◇ UNVERIFIED |
| HNHimco National | Torrance | CA | — | ◇ UNVERIFIED |
| HNHimco Natl INC | Los Angeles | CA | — | ◇ UNVERIFIED |
| HWHinojosas Welding Service LLC | Alice | TX | — | ◇ UNVERIFIED |
| HEHirschfeld Energy Systems, LLC | San Angelo | TX | — | ◇ UNVERIFIED |
| HIHirschfeld Industries | San Angelo | TX | — | ◇ UNVERIFIED |
| HIHirschfeld Industries Group LP | Abilene | TX | — | ◇ UNVERIFIED |
| HIHirschfeld Industries LP | San Angelo | TX | — | ◇ UNVERIFIED |
| HSHi Style Metal Design, Akop Pisikyan Dba | Sun Valley | CA | — | ◇ UNVERIFIED |
 Hi-Tech Metals, Inc. | Maspeth | NY | — | ◇ UNVERIFIED |
| HIHme INC | Topeka | KS | — | ◇ UNVERIFIED |
| HIHme, INC. | Laramie | WY | — | ◇ UNVERIFIED |
| HIHmt, INC. | Blackwell | OK | — | ◇ UNVERIFIED |
| HWHofmeister Welding & Fabricating, INC. | Griggsville | IL | — | ◇ UNVERIFIED |
| HAHof's and Yates Rebar INC Dba H and Y Rebar INC | Long Beach | CA | — | ◇ UNVERIFIED |
| HFHogan Fab INC | Portland | OR | — | ◇ UNVERIFIED |
| HPHogan Products & Services LLC | Pulaski | PA | — | ◇ UNVERIFIED |
| HCHolchris CORP Dba Stahl Mfg of the Bluegrass | Frankfort | KY | — | ◇ UNVERIFIED |
| HMHolland Manufacturing Co., INC. | Dothan | AL | — | ◇ UNVERIFIED |
| HSHolley Steel, Inc. | Elmore | AL | — | ◇ UNVERIFIED |
| HRHolt Repair & Manufacturing INC | Holt | CA | — | ◇ UNVERIFIED |
| HMHomeland Metal Products | Bossier City | LA | — | ◇ UNVERIFIED |
| HCHonor Companies LLC | Sapulpa | OK | — | ◇ UNVERIFIED |
| HBHoof Beat Gates & Corrals | Fallon | NV | — | ◇ UNVERIFIED |
| HHHorns & Hoofs Inc | Vernon Hills | IL | — | ◇ UNVERIFIED |
| HSHorseshoe Steel Erectors | Austin | TX | — | ◇ UNVERIFIED |
| HCHosford & Company | Ann Arbor | MI | — | ◇ UNVERIFIED |
| HLHoss Lee Stairways, INC. | Roseville | CA | — | ◇ UNVERIFIED |
| HPHotcoats Powder Coating | Chico | CA | — | ◇ UNVERIFIED |
| HRHotel & Restaurant Supply INC. | Savannah | TN | — | ◇ UNVERIFIED |
| HOHouse of Forgings, LLC | Houston | TX | — | ◇ UNVERIFIED |
| HFHouston Fab Truck Rigging INC. | Houston | TX | — | ◇ UNVERIFIED |
| HSHoward Structural Steel, Inc. | Saginaw | MI | — | ◇ UNVERIFIED |
 Howmedica Osteonics CORP | Murray | UT | — | ◇ UNVERIFIED |
| HSHowser Steel INC | Portland | OR | — | ◇ UNVERIFIED |
| HRH & R Industrial | Kokomo | IN | — | ◇ UNVERIFIED |
| HIHrke, INC. | Fort Worth | TX | — | ◇ UNVERIFIED |
| HRH R Leuenberger Incorporated | Allison Park | PA | — | ◇ UNVERIFIED |
| HIHsc Investments, INC. | Colfax | NC | — | ◇ UNVERIFIED |
| HCHti Cybernetics | Sterling Heights | MI | — | ◇ UNVERIFIED |
| HHubzco | Saint Louis | MO | — | ◇ UNVERIFIED |
| HMHughes Metal Works, LLC | Greensboro | NC | — | ◇ UNVERIFIED |
| HIHumphrey Industrial Solutions LLC | Bolivar | MO | — | ◇ UNVERIFIED |
| HDHunter Douglas Architectural Products INC. | Norcross | GA | — | ◇ UNVERIFIED |
| HMHunter Metal | Tahoe Vista | CA | — | ◇ UNVERIFIED |
| HTHyperloop Technologies, INC | Moapa | NV | — | ◇ UNVERIFIED |
| HTHy-tech Truck & Trailer Mfg LLC | Fort Morgan | CO | — | ◇ UNVERIFIED |
| IEIan Eddy Blacksmith | Saxtons River | VT | — | ◇ UNVERIFIED |
| IAI & A Properties, LLC | Midland | NC | — | ◇ UNVERIFIED |
| IGIbarra Group LLC | Chicago | IL | — | ◇ UNVERIFIED |
| IFICON Fabrications LLC | Goose Creek | SC | — | ◇ UNVERIFIED |
| IMIcon Metal Works INC Dba Icon Structures | Fontana | CA | — | ◇ UNVERIFIED |
| ISIcon Steel, LLC | Georgetown | TX | — | ◇ UNVERIFIED |
| IIIda Installations, INC. | Southington | CT | — | ◇ UNVERIFIED |
| IPIdeal Portable Buildings & Carports* | West Monroe | LA | — | ◇ UNVERIFIED |
| IPIdeal Products of America | Malvern | PA | — | ◇ UNVERIFIED |
| IMIgnacio Martinez Dba Sunset and Company | Apple Valley | CA | — | ◇ UNVERIFIED |
| IOIhp Operations, LLC | Santa Ana | CA | — | ◇ UNVERIFIED |
| ITIllinois Tool Works INC | Bakersfield | CA | — | ◇ UNVERIFIED |
| IFImperial Fabricating INC. (closed) | Madison | TN | — | ◇ UNVERIFIED |
| IRImperial Rotary Dies | Santa Fe Spgs | CA | — | ◇ UNVERIFIED |
| ISImperial Steel Craft INC | Hillsboro | OR | — | ◇ UNVERIFIED |
| IIIncom, INC. | Kailua Kona | HI | — | ◇ UNVERIFIED |
| ISIndependent Steel LLC | Manassas | VA | — | ◇ UNVERIFIED |
| ISIndiana Steel and Engineering Corporation | Bedford | IN | — | ◇ UNVERIFIED |
| ICIndustrial Contractors | Evansville | IN | — | ◇ UNVERIFIED |
| IDIndustrial Design Fabrication & Installation, INC. | Sioux City | IA | — | ◇ UNVERIFIED |
| IFIndustrial Fabrication Services INC | Lake Crystal | MN | — | ◇ UNVERIFIED |
| IFIndustrial Fabrication Services INC | Lake Crystal | MN | — | ◇ UNVERIFIED |
| IFIndustrial Fabricators | Gastonia | NC | — | ◇ UNVERIFIED |
| IFIndustrial Fabricators INC. | Gastonia | NC | — | ◇ UNVERIFIED |
| IFIndustrial Fabricators, INC - Vc Plant | Gastonia | NC | — | ◇ UNVERIFIED |
| IFIndustrial Fabricators of Virgina INC | Verona | VA | — | ◇ UNVERIFIED |
