What does northwestern corporation do? NorthWestern Corporation. In addition, they are pursuing electric transmission and generation opportunities. NorthWestern Corporation owns NorthWestern Energy, a utility company that serves South Dakota, Nebraska, and Montana that is based in Sioux Falls. As of December 31, 2007, the company serves approximately 650,000 customers.Who owns northwestern energy? NorthWestern Corporation owns NorthWestern Energy, a utility company that serves South Dakota, Nebraska, and Montana that is based in Sioux Falls. As of December 31, 2007, the company serves approximately 650,000 customers.Where is the headquarters of northwestern public service company located? The company's corporate headquarters are located in Sioux Falls while the headquarters for the South Dakota operations (and which was the headquarters for the old NorthWestern Public Service Company) are in Huron, South Dakota .
1994: Northwestern forms the Northwestern Growth Corporation. 1998: Northwestern Public Service changes its name to NorthWestern Corporation. 2000: Company purchases The Montana Power Company's energy distribution and transmission business. Company History: One of the United States' fastest-growing companies, NorthWestern Corporation is a