| HHsv20-yis | Huntsville | AL | 20–99 | ◐ LIKELY ACTIVE |
| HHubbard | Hubbard | OH | 20–99 | ◐ LIKELY ACTIVE |
| HSHuntington Steel & Supply CO | Huntington | WV | — | ◐ LIKELY ACTIVE |
| HFHurtt Fabricating Corp (North Plant) | Marceline | MO | 1–19 | ◐ LIKELY ACTIVE |
| HWH. W. Metal Products, Inc. | Tualatin | OR | 20–99 | ◐ LIKELY ACTIVE |
| HSH&W Stair and Rail LLC | Lincoln | NE | 1–19 | ◐ LIKELY ACTIVE |
| HSHybrid Steel Design LLC | Fort Benton | MT | — | ◐ LIKELY ACTIVE |
| HIHyprio INC. | Mount Pleasant | SC | — | ◐ LIKELY ACTIVE |
| HFHysa Fillers L.l.c. | Golden | CO | — | ◐ LIKELY ACTIVE |
| HPHyspan Precision Products, INC. | Alpharetta | GA | — | ◐ LIKELY ACTIVE |
| IDiDeal Deals, LLC | Saint Augustine | FL | 100–499 | ◐ LIKELY ACTIVE |
| IIfab | Gastonia | NC | 100–499 | ◐ LIKELY ACTIVE |
| IIIfi International Fabrication Industries LLC | Lapeer | MI | — | ◐ LIKELY ACTIVE |
| ILIMIA, LLC Charleston | Goose Creek | SC | 1–19 | ◐ LIKELY ACTIVE |
| ILIMIA, LLC Rosemont Structural | Chesapeake | VA | 20–99 | ◐ LIKELY ACTIVE |
| IFImpact Fab | Holland | MI | 20–99 | ◐ LIKELY ACTIVE |
| IIImperial Iron Works, LLC | Las Vegas | NV | — | ◐ LIKELY ACTIVE |
| ICIndian Creek Fabricators INC. | Tipp City | OH | — | ◐ LIKELY ACTIVE |
| I1Indidge 1 Artistic Metal Works LLC | Independence | MO | — | ◐ LIKELY ACTIVE |
| ISIndustial Steel Constructors | Denham Springs | LA | 1–19 | ◐ LIKELY ACTIVE |
| IMIndustrial Metal Enterprises LLC | Blackfoot | ID | 20–99 | ◐ LIKELY ACTIVE |
| IMIndustrial Metal Works LLC | Newtown | CT | — | ◐ LIKELY ACTIVE |
| IRIndustrial Resources, Inc. | Fairmont | WV | 20–99 | ◐ LIKELY ACTIVE |
| IRIndustrial Rigging Services of Central Texas | Hewitt | TX | 20–99 | ◐ LIKELY ACTIVE |
| ISIndustrial Steel South LLC | Rockledge | FL | 1–19 | ◐ LIKELY ACTIVE |
| IFInfrastructure Fabrication LLC | Bath | PA | — | ◐ LIKELY ACTIVE |
| IMInterior Mobile Welding & Services INC | Fairbanks | AK | — | ◐ LIKELY ACTIVE |
| IGIra G Steffy & Son, Inc. | Ephrata | PA | 100–499 | ◐ LIKELY ACTIVE |
| ISIron Sharpens Iron Welding & Fabricating, INC | Minneola | FL | — | ◐ LIKELY ACTIVE |
| ISIrwin Steel LLC | Justin | TX | 100–499 | ◐ LIKELY ACTIVE |
| ILIstanbul Logistics Aluminum Trading LLC | Vienna | VA | — | ◐ LIKELY ACTIVE |
| IBITW Building Components Group Inc - Earth City, MO | Earth City | MO | 1–19 | ◐ LIKELY ACTIVE |
| IBITW Building Components Group Inc - Ft. Lauderdale | Fort Lauderdale | FL | 20–99 | ◐ LIKELY ACTIVE |
| IBITW Building Components Group Inc - Glenview, IL | Glenview | IL | 500+ | ◐ LIKELY ACTIVE |
| IBITW Building Components Group Inc - Grand Prairie, TX | Grand Prairie | TX | 20–99 | ◐ LIKELY ACTIVE |
| IBITW Building Components Group Inc - Litchfield | Litchfield | IL | 20–99 | ◐ LIKELY ACTIVE |
| IBITW Building Components Group Inc - Orlando | Orlando | FL | 1–19 | ◐ LIKELY ACTIVE |
| IBITW Building Components Group Inc - Pontotoc, MS | Pontotoc | MS | 20–99 | ◐ LIKELY ACTIVE |
| IBITW Building Components Group Inc - Sacramento, CA | Sacramento | CA | 1–19 | ◐ LIKELY ACTIVE |
| JJackson-Cook | Tallahassee | FL | 20–99 | ◐ LIKELY ACTIVE |
| JFJackson Field Welding Services, INC. | Tenino | WA | — | ◐ LIKELY ACTIVE |
| JPJacobs Precision Welding, INC | Lead | SD | — | ◐ LIKELY ACTIVE |
| JZJames Zylstra Enterprises INC | Lafayette | NJ | — | ◐ LIKELY ACTIVE |
| JAJ and D Steel Fabrication and Repair, LP | Santa Maria | CA | 1–19 | ◐ LIKELY ACTIVE |
| JSJasper Steel Works LLC | Williamsport | PA | 1–19 | ◐ LIKELY ACTIVE |
| JTJasper TN | Jasper | TN | 100–499 | ◐ LIKELY ACTIVE |
| JSJeffords Steel and Engineering Company - Plattsburgh | Plattsburgh | NY | 20–99 | ◐ LIKELY ACTIVE |
| JSJeffords Steel and Engineering Company - Potsdam | Potsdam | NY | 20–99 | ◐ LIKELY ACTIVE |
| JCJenidas Corporation DBA Gene Davis Sales and Service | Erie | PA | 20–99 | ◐ LIKELY ACTIVE |
| JJennmar | Cresson | PA | 20–99 | ◐ LIKELY ACTIVE |