NorthWestern Energy LLC - (MT): power outages per year
In 2025 the average NorthWestern Energy LLC - (MT) customer was without power for 2.1 hours, less than the Montana average of 4.8 h; down from 3.9 h in 2024. The utility served 383,135 customers in Montana and ranks #1 of 1 large Montana utilities by outage hours.
By year
| Year | Hours (with major events) | Hours (without) | Interruptions | Customers |
|---|---|---|---|---|
| 2025 | 2.1 | 1.9 | 1.1 | 383,135 |
| 2024 | 3.9 | 2.0 | 1.3 | 376,392 |
| 2023 | 1.7 | 1.7 | 0.9 | 368,707 |
| 2022 | 2.2 | 2.0 | 1.1 | 362,953 |
| 2021 | 2.5 | 2.1 | 1.4 | 367,486 |
| 2020 | 2.8 | 2.0 | 1.1 | 374,593 |
"With major events" includes storm days that utilities may exclude from their own reliability targets; it is what customers actually live through. The gap between the two columns shows how much of the year's outage time came from big storms.
Backup power for NorthWestern Energy LLC - (MT) outages
An average outage here lasted about 1.9 hours in 2025. Size backup for the longest outage you want to ride through, not the average.
FAQ
How many hours a year are NorthWestern Energy LLC - (MT) customers without power?
2.1 hours per customer in 2025 including major event days (1.9 h without them), as NorthWestern Energy LLC - (MT) reported to the U.S. EIA.
How long does a typical NorthWestern Energy LLC - (MT) outage last?
About 1.9 hours on average in 2025 (total outage minutes divided by the number of interruptions). Storms make single events much longer.
Source: U.S. EIA Form 861, Reliability file, 2020–2025. Data snapshot . Utilities ranked nationwide →