| NENorthern Engineering Company LLC | Superior | WI | Fabricated Metal Product Manufacturing332710 | — | ◇ UNVERIFIED |
| NENorthern Engraving CORP | Galesville | WI | Plastics and Rubber Products Manufacturing326120 | — | ◇ UNVERIFIED |
| NMNorthern Metal Fab INC | Baldwin | WI | Fabricated Metal Product Manufacturing332312 | — | ◇ UNVERIFIED |
| NMNorthern Mfg. Co., INC. | Grantsburg | WI | Wood Product Manufacturing321911 | — | ◇ UNVERIFIED |
| NHNorth Hendren Co-op Dairy CO. | Willard | WI | Food Manufacturing311513 | — | ◇ UNVERIFIED |
| NMNorthport Marine, LLC | Gillett | WI | Transportation Equipment Manufacturing336610 | 20-99 | ◇ UNVERIFIED |
| NWNorthview Window & Door, LLC | Marathon | WI | Wood Product Manufacturing321911 | 20-99 | ◇ UNVERIFIED |
| NENyhus Enterprises LLC | Chippewa Falls | WI | Fabricated Metal Product Manufacturing332812 | 1-19 | ◇ UNVERIFIED |
| OFOberlin Filter Company | Pewaukee | WI | Fabricated Metal Product Manufacturing332312 | — | ◇ UNVERIFIED |
| OSOcean Spray Cranberries INC Proc/rec Plant | Wisconsin Rapids | WI | Food Manufacturing311410 | — | ◇ UNVERIFIED |
| OFOem Fabricators INC | Neillsville | WI | Fabricated Metal Product Manufacturing332312 | — | ◇ UNVERIFIED |
| OIO'keefe Incorporated | River Falls | WI | Wood Product Manufacturing321910 | — | ◇ UNVERIFIED |
| OCOrmco CORP Dba Aoa Orthodontic Appliances | Sturtevant | WI | Miscellaneous Manufacturing339116 | — | ◇ UNVERIFIED |
| OCOshkosh CORP - Oakwood Facility | Oshkosh | WI | Machinery Manufacturing333618 | — | ◇ UNVERIFIED |
| OIOshkosh Industrial INC | Oshkosh | WI | Wood Product Manufacturing321990 | — | ◇ UNVERIFIED |
| OCOutagamie Cnty Hwy Dept | Appleton | WI | Machinery Manufacturing333100 | — | ◇ UNVERIFIED |
| OWOve Water Services, INC. | Mukwonago | WI | Beverage and Tobacco Product Manufacturing312112 | 20-99 | ◇ UNVERIFIED |
| OMOwen Manufacturing INC | Owen | WI | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| OFOwens Flooring (quanex Building Products) | Shawano | WI | Wood Product Manufacturing321210 | — | ◇ UNVERIFIED |
| PIPacal Industries LLC | La Crosse | WI | Fabricated Metal Product Manufacturing332312 | — | ◇ UNVERIFIED |
| PIPace Industries - Mole Creek | Grafton | WI | Primary Metal Manufacturing331521 | — | ◇ UNVERIFIED |
| PCPackaging Corporation of America | Colby | WI | Paper Manufacturing322210 | — | ◇ UNVERIFIED |
| PCPactiv - Chippewa Falls | Chippewa Falls | WI | Plastics and Rubber Products Manufacturing326140 | — | ◇ UNVERIFIED |
| PSPalmer-donavin Seal Rite Door | Beloit | WI | Wood Product Manufacturing321911 | — | ◇ UNVERIFIED |
| PHParker Hannifin CORP Refrigerating Specialties Di | Mauston | WI | Fabricated Metal Product Manufacturing332911 | — | ◇ UNVERIFIED |
| PIPemco INC. | Sheboygan | WI | Paper Manufacturing322120 | — | ◇ UNVERIFIED |
| PBPepsi Beverages CO | Oshkosh | WI | Beverage and Tobacco Product Manufacturing312111 | — | ◇ UNVERIFIED |
| PJPerry Judds INC | Waterloo | WI | Printing and Related Support Activities323110 | — | ◇ UNVERIFIED |
| PIPetenwell Industries, LLC. | Necedah | WI | Transportation Equipment Manufacturing336214 | 1-19 | ◇ UNVERIFIED |
| POPhillips-medisize - Origen | Menomonie | WI | Primary Metal Manufacturing331528 | — | ◇ UNVERIFIED |
| PPPhillips Plastics CORP - Custom I | Phillips | WI | Plastics and Rubber Products Manufacturing326100 | — | ◇ UNVERIFIED |
| PPPhillips Plastics CORP Custom Ii | Phillips | WI | Plastics and Rubber Products Manufacturing326199 | — | ◇ UNVERIFIED |
| PHP & H Mining Equipment | Milwaukee | WI | Fabricated Metal Product Manufacturing332312 | — | ◇ UNVERIFIED |
| PCPhoenix Coaters LLC | Berlin | WI | Fabricated Metal Product Manufacturing332810 | — | ◇ UNVERIFIED |
| PMPierce Manufacturing - Fabrication Plant | Appleton | WI | Transportation Equipment Manufacturing336120 | — | ◇ UNVERIFIED |
| PMPierce Manufacturing, INC. - Neenah | Neenah | WI | Transportation Equipment Manufacturing336120 | — | ◇ UNVERIFIED |
 Pinnacle Precision INC | Racine | WI | Fabricated Metal Product Manufacturing332116 | — | ◇ UNVERIFIED |
| PWPitlik & Wick, INC. - Clear Lake Aggregate Source | Minocqua | WI | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| PWPitlik & Wick, INC. - Highway D Aggregate Source | Minocqua | WI | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| PFPjk Finishing CO INC | Menomonee Falls | WI | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| PEPlating Engineering | Milwaukee | WI | Fabricated Metal Product Manufacturing332810 | — | ◇ UNVERIFIED |
| PPPleasant Prairie Power Plant | Pleasant Prairie | WI | Plastics and Rubber Products Manufacturing326199 | — | ◇ UNVERIFIED |
| PWPolar Ware CO | Sheboygan | WI | Fabricated Metal Product Manufacturing332116 | — | ◇ UNVERIFIED |
| PCPolyone CORP (former) | Sussex | WI | Chemical Manufacturing325211 | — | ◇ UNVERIFIED |
| PVPoly Vinyl CO INC | Kohler | WI | Plastics and Rubber Products Manufacturing326120 | — | ◇ UNVERIFIED |
| PGPpg Gp LLC | Milwaukee | WI | Chemical Manufacturing325130 | — | ◇ UNVERIFIED |
| PBPraefke Brake & Supply CORP | West Bend | WI | Transportation Equipment Manufacturing336340 | — | ◇ UNVERIFIED |
| PSPrecision Screw Products., INC. of Janesville | Janesville | WI | Fabricated Metal Product Manufacturing332721 | 1-19 | ◇ UNVERIFIED |
| PTPrecision Twist Drill CO - Rhinelander | Rhinelander | WI | Machinery Manufacturing333515 | — | ◇ UNVERIFIED |
| PPPremium Prefinished Products, INC. | Sun Prairie | WI | Chemical Manufacturing325510 | — | ◇ UNVERIFIED |
