NorthWestern Energy Group, Inc. engages in the provision of electricity and natural gas to customers in Montana, South Dakota, Nebraska, and Yellowstone National Park. It operates through the following segments: Electric, Natural Gas, and Other. The Electric segment is involved in the regulated electric utility business primarily providing generation, transmission, and distribution services to customers in the Montana and South Dakota jurisdictions. The Natural Gas segment focuses on the natural gas utility business primarily providing production, storage, transmission, and distribution services to customers in the Montana, South Dakota, and Nebraska jurisdictions. The company was founded in November 1923 and is headquartered in Sioux Falls, SD.