How much does a space heater cost per month in Montana?

About $11.21 a month, assuming 1,500 W at a 60% duty cycle, 8 hours a day, 120 days a year at 15.57¢/kWh.

How many kilowatt-hours does a space heater use?

Roughly 864 kWh a year under these assumptions, or 0.90 kWh for every hour it runs.

Is that expensive compared with other states?

Montana has the 19th cheapest average residential rate in the country, so this appliance costs less here than the U.S. average of $157 a year.

Home › Space heater › Montana

Cost to run a space heater in Montana (August 2026 rates)

At 15.57¢ per kilowatt-hour — Montana's average residential price in August 2026 — running a space heater costs $135 a year. That is 14% less than the national average of $157. Montana's residential rate is up 9.0% from August 2025, which moves this appliance from $123 to $135 a year.

Per hour: 14.0¢
Per day of use: $1.12
Per month: $11.21
Per year: $135

Assumption: 1,500 W at a 60% duty cycle, 8 hours a day, 120 days a year — 864 kWh a year. 1,500 W is the ceiling for a 120 V plug-in heater, and nearly every model sold hits it on high. A thermostat changes how often it runs, not how hard. Use the calculator to swap in the numbers from your own model.

How Montana compares

Montana pays 15.57¢/kWh, the 19th cheapest residential electricity of the 51 U.S. jurisdictions EIA reports. For this appliance that works out to $22.38 less a year than the typical U.S. household pays for the same use. Running the same space heater costs $110 a year in Nevada and $408 in Hawaii, so where you live changes this bill by $298 a year.

State	Rate	Per month	Per year
South Dakota	15.15¢	$10.91	$131
Kansas	15.47¢	$11.14	$134
Montana	15.57¢	$11.21	$135
South Carolina	15.76¢	$11.35	$136
Georgia	15.90¢	$11.45	$137

States ranked by average residential price, cheapest first. See all 51 states for a space heater.

What else costs about the same in Montana

Portable air conditioner$132 a year in MT Garage refrigerator$140 a year in MT Electric clothes dryer$121 a year in MT

Cutting the number down

Heating one occupied room and letting the rest of the house sit cooler is the whole case for a space heater. Running one in every room costs more than central heat.
Ceramic, oil-filled and infrared heaters all convert essentially 100% of the electricity to heat. At the same wattage the running cost is identical, whatever the box claims.
The cheapest watt is the one you skip: closing the door to the room you are heating does more than any model upgrade.

Questions

How much does a space heater cost per month in Montana?: About $11.21 a month, assuming 1,500 W at a 60% duty cycle, 8 hours a day, 120 days a year at 15.57¢/kWh.
How many kilowatt-hours does a space heater use?: Roughly 864 kWh a year under these assumptions, or 0.90 kWh for every hour it runs.
Is that expensive compared with other states?: Montana has the 19th cheapest average residential rate in the country, so this appliance costs less here than the U.S. average of $157 a year.