Montana did not have a rate change on October 1, 2026. NorthWestern Energy, the state’s largest utility, put new electric rates in place on February 1 after a long rate case.
This article covers NorthWestern Energy. It does not cover Montana-Dakota Utilities or the electric cooperatives.
Quick Summary
| Item | Detail |
|---|---|
| Decision | December 24, 2025 |
| Effective | February 1, 2026 |
| Residential base rates | +17% |
| Overall residential bill | About +12% |
| Return on equity | 9.65% |
| Gas plant cost in rates | $246.06 million rate base; about $8 a month per typical customer |
Source: Missoula Current.
What Was Decided
The Montana Public Service Commission (PSC) approved:
- A 17% permanent increase in residential electric base rates. Because base rates are only part of the bill, the total rises about 12%.
- Recovery of the Yellowstone County Generating Station, a natural gas plant, at a rate base of $246.06 million. NorthWestern asked for $287 million. PSC staff recommended $227.7 million.
- A 9.65% return on equity.
The case took about 16 months. Customers had been paying interim rates while it was pending.
The Gas Plant Cost
The Missoula Current reported the plant adds about $8 a month, about $100 a year, to a typical residential bill, plus more than $35 million a year in variable costs across all customers. It also reported that PSC staff found NorthWestern “did not satisfy its burden of proof” on part of the cost recovery.
Recent History
This was NorthWestern’s second increase in a short period. The PSC approved a settlement in October 2023 that raised a typical residential electric bill about $8 a month at 750 kWh.
What This Means for Homeowners With Solar
We did not verify Montana’s current net metering or export credit rules for this article, so we give no export rates here. Ask your utility for its current solar tariff, and check how exported energy is credited before sizing a system. Fixed monthly charges are not reduced by solar.
Our solar payback guide shows how the retail rate and the export credit change the math.
What to Check on Your Bill
- The service charge.
- The delivery and supply lines since February 2026.
- Any credit or charge reconciling interim rates with final rates.
For help sorting the lines on your bill, see our guide to reading your electric bill.
Limitations
The 2026 figures come from one news report, which drew on an environmental group’s analysis. We did not open the PSC order, and we did not confirm how interim rates were reconciled.
Sources
- Missoula Current, “Groups respond to PSC approval of customer rate increase”
- KTVH, “Montana PSC approves NorthWestern Energy rate increases,” Oct. 2023
- Montana Free Press via MSU Exponent, “After 16 months, PSC approves $246 million rate increase for NorthWestern customers”
Frequently asked questions
Did Montana electric rates change on October 1, 2026?
We found no change on that date. NorthWestern Energy's new rates took effect February 1, 2026.
How much did NorthWestern Energy rates go up in 2026?
Residential electric base rates rose 17%, which works out to about 12% on an overall bill, according to the Missoula Current's report of the December 24, 2025 decision.
What is the Yellowstone County Generating Station charge?
The cost of a natural gas plant near Laurel that regulators added to rates. It is reported at about $8 a month, or about $100 a year, for a typical residential customer.
