NorthWestern Energy electricity rates
NorthWestern Energy charges an average of 12.56 cents per kilowatt-hour to residential customers, and the average household on its system paid $113 a month using 903 kilowatt-hours, according to its 2024 filing with the U.S. Energy Information Administration.
Investor-owned utility SWPP South Dakota
Where NorthWestern Energy sits
It serves 51,467 residential customers in South Dakota. At 12.56¢ per kilowatt-hour it is one of the cheaper places to buy electricity in South Dakota, 20.2% under the statewide average of 15.73¢.
Consumption is close to the national norm at 903 kilowatt-hours a month against 871, so the rate translates fairly directly into the bill.
A shareholder-owned company whose rates are set by the state regulator, including an approved return on the capital it has invested. That matters because a bill is not only the cost of generating electricity: it also carries the cost of the network, and who owns that network changes how it is paid for.
| Rate | Monthly bill | Monthly kWh | |
|---|---|---|---|
| NorthWestern Energy | 12.56¢ | $113 | 903 |
| South Dakota average | 15.73¢ | $138 | 981 |
| United States average | 18.44¢ | $155 | 871 |
Utility figures: U.S. Energy Information Administration, Form EIA-861 annual electric power industry report, 2024. State and national figures: Electric Power Monthly, May 2026. Methodology
Where NorthWestern Energy delivers
Its service territory covers 27 South Dakota counties, either wholly or in part. Utility boundaries follow historic franchise agreements rather than county lines, so a county appearing here does not mean every address in it is served by NorthWestern Energy.
- Aurora
- Beadle
- Bon Homme
- Brown
- Brule
- Charles Mix
- Clark
- Codington
- Davison
- Day
- Deuel
- Douglas
- Edmunds
- Faulk
- Hamlin
- Hand
- Hanson
- Hughes
- Hutchinson
- Hyde
- Jerauld
- Kingsbury
- Marshall
- Sanborn
- Spink
- Turner
- Yankton
How often the power goes out
In 2024 the average NorthWestern Energy customer went 76 minutes without electricity across 0.7 interruptions. The median across the 941 utilities that report this is 185 minutes.
That is markedly better than typical. Short outage durations usually mean an underground or heavily automated network, and they are expensive to achieve, which is part of why reliable systems often carry higher delivery charges.
Other South Dakota utilities
| Utility | Rate | Bill | Customers |
|---|---|---|---|
| Northern States Power Co - Minnesota | 13.87¢ | $103 | 92,204 |
| Black Hills Power, Inc. | 14.37¢ | $110 | 60,951 |
| Sioux Valley SW Elec Coop | 12.94¢ | $160 | 22,213 |
| Southeastern Electric Coop Inc | 12.41¢ | $140 | 20,160 |
| West River Electric Assn Inc | 14.25¢ | $128 | 18,423 |
NorthWestern Energy rates: common questions
How much does NorthWestern Energy charge per kilowatt-hour?
An average of 12.56 cents per kilowatt-hour across its residential customers in 2024. That is -20.2% against the South Dakota average of 15.73¢ and -31.9% against the national average of 18.44¢. It is an all-in average across every residential rate schedule the utility offers, not a specific tariff.
What is the average NorthWestern Energy bill?
$113 a month, based on total residential revenue divided by residential customers over the 2024 survey year, at an average of 903 kWh a month. The national average bill is $155 at 871 kWh.
Who owns NorthWestern Energy?
It is classified by the EIA as a investor-owned utility. A shareholder-owned company whose rates are set by the state regulator, including an approved return on the capital it has invested.
Is NorthWestern Energy expensive compared with other South Dakota utilities?
It ranks #10 of the 20 South Dakota utilities covered here, counting from the most expensive. Nationally it ranks #895 of 1369.