| FCFirst Choice Ingredients - Menomonee Falls | Menomonee Falls | WI | Food Manufacturing311942 | 20-99 | ◐ LIKELY ACTIVE |
| FSFluid System Components INC | Depere | WI | Fabricated Metal Product Manufacturing332912 | 20-99 | ◐ LIKELY ACTIVE |
| FFForemost Farms USA (Marshfield, WI) | Marshfield | WI | Food Manufacturing311510 | 20-99 | ◐ LIKELY ACTIVE |
| FFForemost Farms USA (Reedsburg, WI) | Reedsburg | WI | Food Manufacturing311510 | 20-99 | ◐ LIKELY ACTIVE |
| FEFranklin Electric Fueling Systems Deforest | Deforest | WI | Plastics and Rubber Products Manufacturing326199 | — | ◐ LIKELY ACTIVE |
| FMFrantz Machine Products Inc. | New Berlin | WI | Fabricated Metal Product Manufacturing332710 | 20-99 | ◐ LIKELY ACTIVE |
| FFFromm Family Foods, LLC | Mequon | WI | Food Manufacturing311111 | 20-99 | ◐ LIKELY ACTIVE |
| GHGardan - Hortonville | Hortonville | WI | Computer and Electronic Product Manufacturing334419 | 20-99 | ◐ LIKELY ACTIVE |
| GCGe CO Medical Systems | Waukesha | WI | Computer and Electronic Product Manufacturing334517 | — | ◐ LIKELY ACTIVE |
| GPGenerac Power Systems | Whitewater | WI | Electrical Equipment, Appliance & Component Manufacturing335312 | — | ◐ LIKELY ACTIVE |
General Mills / Gardettos | Milwaukee | WI | Food Manufacturing311812 | 100-499 | ◐ LIKELY ACTIVE |
| GAGenesis Attachments | Superior | WI | Machinery Manufacturing333120 | 100-499 | ◐ LIKELY ACTIVE |
| GMG&G Machine Inc. | Kaukauna | WI | Fabricated Metal Product Manufacturing332710 | 20-99 | ◐ LIKELY ACTIVE |
| GIGHL International Inc | Cedarburg | WI | Chemical Manufacturing325998 | 20-99 | ◐ LIKELY ACTIVE |
| GIGlass Insulators, INC. | Bloomer | WI | Nonmetallic Mineral Product Manufacturing327211 | 20-99 | ◐ LIKELY ACTIVE |
| GRGlenn Rieder INC | West Allis | WI | Wood Product Manufacturing321918 | 100-499 | ◐ LIKELY ACTIVE |
| GWGoetsch's Welding & Machine, Inc. | Merrill | WI | Fabricated Metal Product Manufacturing332999 | 20-99 | ◐ LIKELY ACTIVE |
| GLGomacro, LLC | Viola | WI | Food Manufacturing311991 | 100-499 | ◐ LIKELY ACTIVE |
| GMGranite Microsystems, INC. | Mequon | WI | — | 20-99 | ◐ LIKELY ACTIVE |
| GWGraymont Western Lime Green Bay | Green Bay | WI | Nonmetallic Mineral Product Manufacturing327410 | — | ◐ LIKELY ACTIVE |
| GLGreat Lakes Custom Tool Manufacturing, Inc. | Peshtigo | WI | Machinery Manufacturing333515 | 20-99 | ◐ LIKELY ACTIVE |
| GNGreat Northern Corporation - Chippewa Falls | Chippewa Falls | WI | Paper Manufacturing322211 | 100-499 | ◐ LIKELY ACTIVE |
| GLGrede LLC - Liberty | Wauwatosa | WI | Primary Metal Manufacturing331510 | — | ◐ LIKELY ACTIVE |
| GBGreen Bay Packaging- Great Lakes Division | Germantown | WI | Paper Manufacturing322211 | 20-99 | ◐ LIKELY ACTIVE |
| GBGreen Bay Packaging INC -folding Carton Div | De Pere | WI | Paper Manufacturing322212 | 100-499 | ◐ LIKELY ACTIVE |
| GAGulfstream Aerospace Corporation | Appleton | WI | Transportation Equipment Manufacturing336411 | 500+ | ◐ LIKELY ACTIVE |
| HSH & S Manufacturing Company INC | Clintonville | WI | Machinery Manufacturing333111 | — | ◐ LIKELY ACTIVE |
| HFHartford Finishing INC | Hartford | WI | Fabricated Metal Product Manufacturing332810 | 100-499 | ◐ LIKELY ACTIVE |
| HRHawk Research Laboratories LLC | West Bend | WI | Chemical Manufacturing325510 | — | ◐ LIKELY ACTIVE |
| HPHearing Protection LLC | Watertown | WI | Fabricated Metal Product Manufacturing332999 | 20-99 | ◐ LIKELY ACTIVE |
Hentzen Coatings, INC. | Milwaukee | WI | Chemical Manufacturing325510 | 20-99 | ◐ LIKELY ACTIVE |
| HWHG Weber and Company, Inc. | Kiel | WI | Machinery Manufacturing333993 | 20-99 | ◐ LIKELY ACTIVE |
| HSHolcim Solutions and Products US LLC | Waukesha | WI | Chemical Manufacturing325510 | — | ◐ LIKELY ACTIVE |
| HBHorseshoe Beverage Company | Neenah | WI | Beverage and Tobacco Product Manufacturing312111 | 100-499 | ◐ LIKELY ACTIVE |
| HMHudapack Metal Treating INC | Elkhorn | WI | Fabricated Metal Product Manufacturing332811 | 20-99 | ◐ LIKELY ACTIVE |
| HIHydra-Seal, Inc. | Menomonee Falls | WI | Fabricated Metal Product Manufacturing332999 | 20-99 | ◐ LIKELY ACTIVE |
| HCHydrite Chemical CO. | Cottage Grove | WI | Chemical Manufacturing325000 | — | ◐ LIKELY ACTIVE |
| HEHydro Electronic Devices, Inc. | Hartford | WI | Electrical Equipment, Appliance & Component Manufacturing335314 | 20-99 | ◐ LIKELY ACTIVE |
| HIHyPro Inc. Jefferson (JF) | Waterford | WI | Fabricated Metal Product Manufacturing332710 | 20-99 | ◐ LIKELY ACTIVE |
| IIIap INC | Phillips | WI | Fabricated Metal Product Manufacturing332313 | 20-99 | ◐ LIKELY ACTIVE |
| IIIea INC | Kenosha | WI | Machinery Manufacturing333414 | 100-499 | ◐ LIKELY ACTIVE |
| IIIKS Industries, Inc. | Park Falls | WI | Fabricated Metal Product Manufacturing332710 | 20-99 | ◐ LIKELY ACTIVE |
| ILIndeck Ladysmith LLC | Ladysmith | WI | Wood Product Manufacturing321999 | 20-99 | ◐ LIKELY ACTIVE |
| IPIndependent Printing CO INC | De Pere | WI | Printing and Related Support Activities323110 | 100-499 | ◐ LIKELY ACTIVE |
| IMInjection Molding Solutions, INC. | Siren | WI | Plastics and Rubber Products Manufacturing326199 | 20-99 | ◐ LIKELY ACTIVE |
| IWInnio Waukesha Gas Engines, INC. | Waukesha | WI | Machinery Manufacturing333618 | 100-499 | ◐ LIKELY ACTIVE |
| ICInpro Corporation - Apollo South | Muskego | WI | Plastics and Rubber Products Manufacturing326191 | — | ◐ LIKELY ACTIVE |
| IMIntek Medford, LLC | Medford | WI | Plastics and Rubber Products Manufacturing326199 | 20-99 | ◐ LIKELY ACTIVE |
| IPInternational Paper - Manitowoc | Manitowoc | WI | Paper Manufacturing322210 | 100-499 | ◐ LIKELY ACTIVE |
Intuitive Biosciences INC | Madison | WI | Chemical Manufacturing325413 | 1-19 | ◐ LIKELY ACTIVE |