| PBPink Bench Distilling | Troy | MT | Beverage and Tobacco Product Manufacturing312140 | — | ◐ LIKELY ACTIVE |
| PDPioneer Dental Studio INC | Helena | MT | Miscellaneous Manufacturing339116 | — | ◐ LIKELY ACTIVE |
| PJPj & J INC | Great Falls | MT | Fabricated Metal Product Manufacturing332618 | — | ◐ LIKELY ACTIVE |
| PRPortal Rum Distillery | Kalispell | MT | Beverage and Tobacco Product Manufacturing312140 | — | ◐ LIKELY ACTIVE |
| PPrintingCenterUSA | Great Falls | MT | Printing and Related Support Activities323111 | 20-99 | ◐ LIKELY ACTIVE |
| PRP & R Mummey, INC. | Malta | MT | Petroleum and Coal Products Manufacturing324121 | — | ◐ LIKELY ACTIVE |
| PPProducers Partnership | Livingston | MT | Food Manufacturing311611 | — | ◐ LIKELY ACTIVE |
| PIPro Install INC. | Billings | MT | Furniture and Related Product Manufacturing337214 | — | ◐ LIKELY ACTIVE |
| PMProject Meats LLC | Billings | MT | Food Manufacturing311612 | — | ◐ LIKELY ACTIVE |
| QFQb Fueling, INC | Frenchtown | MT | Petroleum and Coal Products Manufacturing324110 | — | ◐ LIKELY ACTIVE |
| RKRader K9 LLC | Ismay | MT | Leather and Allied Product Manufacturing316990 | — | ▲ REPORTED CLOSED |
| RBRanchers' Best Meats | Miles City | MT | Food Manufacturing311611 | — | ◐ LIKELY ACTIVE |
| RHRanch House Snacks | Billings | MT | Food Manufacturing311612 | — | ◐ LIKELY ACTIVE |
| RCRattlesnake Creek Distillers | Missoula | MT | Beverage and Tobacco Product Manufacturing312140 | — | ◐ LIKELY ACTIVE |
| RLRed Lodge Ales Brewing Company | Red Lodge | MT | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
Remsight LLC | Hamilton | MT | Computer and Electronic Product Manufacturing334513 | — | ◐ LIKELY ACTIVE |
| RLResearch Lab Source INC | Bozeman | MT | Computer and Electronic Product Manufacturing334515 | — | ◐ LIKELY ACTIVE |
| RARhino Ammunitions, LLC | Frenchtown | MT | Fabricated Metal Product Manufacturing332994 | — | ◐ LIKELY ACTIVE |
| RMRiley's Meats | Butte | MT | Food Manufacturing311612 | — | ◐ LIKELY ACTIVE |
| RLR. L. Armacost, INC. | Great Falls | MT | Computer and Electronic Product Manufacturing334512 | — | ◐ LIKELY ACTIVE |
| RMRocky Mountain Twist Corp | Ronan | MT | Machinery Manufacturing333515 | 100-499 | ◐ LIKELY ACTIVE |
| RRR & R Fence CO LLC | Winifred | MT | Fabricated Metal Product Manufacturing332618 | — | ◐ LIKELY ACTIVE |
| SDSangria Del Sol LLC | Bozeman | MT | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
| SLSapphire Lumber Company | Hamilton | MT | Wood Product Manufacturing321912 | — | ◐ LIKELY ACTIVE |
| SBSEL Butte MT | Butte | MT | Electrical Equipment, Appliance & Component Manufacturing335314 | 1-19 | ◐ LIKELY ACTIVE |
| SHShed Horn Cellars | Hamilton | MT | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
Shield Pest Defense LLC | Missoula | MT | Chemical Manufacturing325320 | — | ◐ LIKELY ACTIVE |
| SLShroombob LLC | Bozeman | MT | Miscellaneous Manufacturing339920 | — | ◐ LIKELY ACTIVE |
| SASieler Allen | Kalispell | MT | Transportation Equipment Manufacturing336214 | — | ◐ LIKELY ACTIVE |
| SPSierra Pacific Windows-Montana | Missoula | MT | Wood Product Manufacturing321911 | 1-19 | ◐ LIKELY ACTIVE |
| SXSimi Xest Sqeltc Sukaxni ni A Kulak of Selis Qlispe and Ksanka, Inc. | Ronan | MT | Food Manufacturing311611 | — | ◐ LIKELY ACTIVE |
| SASine Advanced Engineering, INC. | Big Sky | MT | Computer and Electronic Product Manufacturing334511 | — | ◐ LIKELY ACTIVE |
| SSSine Strategic Group, INC. | Bozeman | MT | Computer and Electronic Product Manufacturing334511 | — | ◐ LIKELY ACTIVE |
| SNSitech Northwest INC. | Billings | MT | Computer and Electronic Product Manufacturing334511 | — | ◐ LIKELY ACTIVE |
| SNSmartLam NA Columbia Falls LLC | Columbia Falls, MT | MT | Wood Product Manufacturing321213 | 20-99 | ◐ LIKELY ACTIVE |
| SSSmart Step Surgical LLC | Billings | MT | Miscellaneous Manufacturing339112 | — | ◐ LIKELY ACTIVE |
| SBSpotted Bear Spirits LLC | Whitefish | MT | Beverage and Tobacco Product Manufacturing312140 | — | ◐ LIKELY ACTIVE |
| SISpruce Industries LLC | Bozeman | MT | Fabricated Metal Product Manufacturing332710 | — | ◐ LIKELY ACTIVE |
| SRS Ranch Meats LLC | Hardin | MT | Food Manufacturing311612 | — | ◐ LIKELY ACTIVE |
| SRS Ranch Meats, LLC | Hardin | MT | Food Manufacturing311611 | — | ◐ LIKELY ACTIVE |
| SISse Investment Group LLC | Great Falls | MT | Wood Product Manufacturing321992 | — | ◐ LIKELY ACTIVE |
| SISSP-SiMatrix, Inc. - Victor | Victor | MT | Miscellaneous Manufacturing339113 | 20-99 | ◐ LIKELY ACTIVE |
| SIStagefx, INC. | Columbus | MT | Chemical Manufacturing325920 | — | ◐ LIKELY ACTIVE |
| SPStahl Peak Distillery, LLC | Eureka | MT | Beverage and Tobacco Product Manufacturing312140 | — | ◐ LIKELY ACTIVE |
| SMStevensville, MT | Stevensville | MT | Plastics and Rubber Products Manufacturing326122 | 20-99 | ◐ LIKELY ACTIVE |
| SMStillwater Mining Company Base Metals Smelter | Columbus | MT | Primary Metal Manufacturing331410 | 20-99 | ◐ LIKELY ACTIVE |
| SDStonehouse Distillery LLC | Winston | MT | Beverage and Tobacco Product Manufacturing312140 | — | ◐ LIKELY ACTIVE |
| SSSuperior Satellite Engineers INC | Columbia Falls | MT | Computer and Electronic Product Manufacturing334220 | — | ◐ LIKELY ACTIVE |
| SSSwanson's Spirits | Corvallis | MT | Beverage and Tobacco Product Manufacturing312140 | — | ◐ LIKELY ACTIVE |
| SVSwan Valley Medical, INC | Bigfork | MT | Miscellaneous Manufacturing339112 | — | ◐ LIKELY ACTIVE |