NorthWestern Energy

NorthWestern Energy Group, Inc. is a utility company that serves South Dakota, Nebraska, and Montana that is based in Sioux Falls., the company serves approximately 718,000 customers. The company's corporate headquarters are located in Sioux Falls while the headquarters for the South Dakota operations are in Huron, South Dakota.

History

The Montana operations were acquired around 2000 after that state passed legislation allowing the electric utility industry to be 'unbundled'. Out of state investors then immediately acquired the generation assets of Montana Power, leaving that part of the territory vulnerable to high "spot" prices on the energy market. In 2014, NorthWestern purchased the dams that were originally part of Montana Power for $900 Million from PPL Corporation.
In August 2025, NorthWestern and Black Hills Corporation agreed to a merger in an all-stock deal valuing the combined entity at $15.4 billion. Once completed, NorthWestern shareholders will own about 46% of the combined company and will be run by NorthWestern's CEO, Brian Bird.

Controversies

In March, 2003, a class action was filed against Northwestern Corp, claiming that defendants artificially inflated the stock price through material omissions and materially false and misleading statements. A $41 million settlement fund was established in 2005.
In March 2009, NorthWestern Energy was involved with a gas explosion in Bozeman, Montana. The explosion destroyed several businesses and killed one person. By November, the company was sued by numerous owners of the destroyed businesses.