Helena, Montana: PSC Approves $15.4 Billion NorthWestern Energy and Black Hills Merger in Final State Vote

The Montana Public Service Commission voted 3 to 2 on Tuesday to approve the $15.4 billion merger of NorthWestern Energy and Black Hills Corp., the last state approval the two utilities needed to combine. The vote came at the commission offices in Helena, after a year of hearings on power bills, future energy supply and local control.

A split vote in Helena

Commissioners Jennifer Fielder, Annie Bukacek and Kirk Bushman voted yes. Commission President Jeff Welborn voted no and called his vote a reluctant one. Commissioner Randy Pinocci also voted no. Fielder, who made the motion to approve, said the evidence showed the merger would produce "tens of millions of dollars in savings" for the companies. "Those savings are savings that get passed onto the customers," Fielder said. "Those are costs the customers will not have to pay." Bukacek said staff had addressed every argument raised against the merger. Welborn said he saw no clear gain for Montana. "I don't see where there's a clear benefit to advance the public's interest here," he said.

What customers told the commission

Most members of the public who spoke before the vote opposed the deal, raising higher power bills, weaker oversight and the risk that residents would pay for energy built for data centers. Jan Hoem of Missoula asked for a fixed rate for two years. "Your job is to see that we, the captive customers, get a fair shake," Hoem said. "We're counting on you." Patrick Sheehy of Billings, a senior citizen on a fixed income, asked for consumer protections. "I am very concerned that in the long run, this merger is going to result in ratepayers like me paying exorbitant sums of money to NorthWestern Energy," he said. The approved order says rates will not increase as a result of the merger, and it found the ring fencing safeguards adequate to shield NorthWestern customers from financial risks at the new parent company.

The Colstrip conditions

Before the final vote, Fielder proposed two conditions, and the commission adopted them 3 to 2, with Bukacek and Welborn opposed. The first directs NorthWestern to submit a plan to the PSC by June 2027 that evaluates whether part of the generation the utility acquired at the Colstrip Power Plant could serve Montana customers as a potential least cost electricity supply resource. NorthWestern announced in 2024 that it would acquire Puget Sound Energy's 370 megawatts at Colstrip, then later said the shares would sit in a subsidiary outside regulator control. The second condition directs NorthWestern to analyze adding the Puget shares to its portfolio in the 2026 Integrated Resource Plan. Pinocci said the Colstrip power should already let NorthWestern lower rates. "What are we going to do about lowering the rates for the people?" he said.

What happens next

South Dakota and Nebraska regulators approved the deal earlier, and NorthWestern said it has secured federal approvals. The all stock merger was announced in August 2025. The combined company will serve about 2.1 million customers in Montana, Arkansas, Colorado, Iowa, Kansas, South Dakota, Nebraska and Wyoming. When the deal closes, the parent will be called Bright Horizon Energy, and NorthWestern Energy will be its wholly owned subsidiary. NorthWestern spokeswoman Jo Dee Black said officials will review the order and still believe the merger serves customers.