Running cost comes down to wattage, hours and your rate. In Montana the rate is 14.67 cents per kWh, which is 20.4 percent below the national average. Here is what that means for a space heater.
A space heater drawing 1,500 W costs $0.22 per hour in Montana. Run 6 hours a day that is $1.32 daily, $39.61 a month and $482 a year, which is $124 less than the same appliance at the US average rate.
Cost by hours used per day in Montana
| Hours/day | Energy | Per day | Per month |
|---|---|---|---|
| 1 h | 1.50 kWh | $0.22 | $6.60 |
| 2 h | 3.00 kWh | $0.44 | $13.20 |
| 4 h | 6.00 kWh | $0.88 | $26.41 |
| 6 h | 9.00 kWh | $1.32 | $39.61 |
| 8 h | 12.00 kWh | $1.76 | $52.81 |
| 12 h | 18.00 kWh | $2.64 | $79.22 |
| 24 h | 36.00 kWh | $5.28 | $158 |
Cost by wattage at 14.67 cents
| Rated power | Per hour | Per day | Per month |
|---|---|---|---|
| 500 W | $0.07 | $0.44 | $13.20 |
| 750 W | $0.11 | $0.66 | $19.80 |
| 1,000 W | $0.15 | $0.88 | $26.41 |
| 1,200 W | $0.18 | $1.06 | $31.69 |
| 1,500 W | $0.22 | $1.32 | $39.61 |
Find the row matching the nameplate on your own unit. Within a single appliance category the spread is often wider than the difference between categories, so the label is worth reading.
Heating season in Montana
Montana has a long, hard heating season, and that makes electric resistance heat expensive here in a way it is not in milder states. A heat pump delivering two to three units of heat per unit of electricity changes the arithmetic substantially, though capacity does fall as outdoor temperature drops, so sizing for design temperature matters more here than almost anywhere.
Why Montana pays what it does
Montana is a regulated market, so your utility is the only supplier and the rate is set through the state commission rather than by competition. Pricing tends to be steadier than in deregulated states, and there is no switching decision available. The levers are all on your side of the meter.
At 14.67 cents, Montana ranks 13 of 51 from cheapest to most expensive. The West regional average is 19.65 cents. Roughly half of any residential bill is transmission and distribution rather than generation, which is why rates keep climbing even when fuel prices fall.
How this compares across the country
The same space heater on the same schedule, in the cheapest and dearest states:
| State | Rate | Per month | Per year |
|---|---|---|---|
| Idaho | 12.35¢ | $33.35 | $406 |
| Utah | 12.96¢ | $34.99 | $426 |
| Montana | 14.67¢ | $39.61 | $482 |
| California | 33.25¢ | $89.78 | $1,092 |
| Hawaii | 52.00¢ | $140 | $1,708 |
Lowering the number in Montana
- Use the low setting when it holds temperature. 750 W instead of 1,500 W halves the running cost.
- Put it on a timer or smart plug. The biggest waste is a heater running in an empty room.
- Turn the central thermostat down at the same time. Adding a space heater without lowering the house setpoint adds cost and removes nothing.
- Close the door and block the draft under it. Zone heating only saves money if the zone is sealed.
- One heater per circuit, plugged into the wall. A 1,500 W heater draws 12.5 amps, which is already at the continuous limit for a 15 A circuit.
- In Montana, air sealing pays back faster than equipment upgrades. A long heating season multiplies every draft, and sealing is cheap compared with replacing hardware.
Offsetting it with solar in Montana
This load uses about 9.00 kWh a day. Covering that would take roughly 7 standard 400 W panels at typical sun hours, an array of about 2.80 kW. Because it offsets electricity worth 14.67 cents rather than the national 18.44 cents, the same array is worth less here than the national payback figures suggest.
Resistance heating is the worst possible solar load. It draws full rated power the whole time it runs and there is no efficiency to gain, so the panel count is driven purely by hours of use. Full sizing, including battery and inverter requirements, is on the solar sizing page for this appliance.
Questions people actually ask
[hed_faq]How much does it cost to run a space heater in Montana?About $0.22 per hour and $39.61 a month at 6 hours a day, using the Montana average rate of 14.67 cents per kWh.
How many watts does a space heater use?Around 1,500 W while running, with a range of roughly 500 to 1,500 W depending on model and setting.
Is that expensive for Montana?Montana electricity runs 20.4 percent below the national average, so this appliance costs $124 less per year here than it would at the US average rate.
Can I lower this without replacing the appliance?Usually yes. Run time is the variable you control, and the hours table above shows exactly what each hour costs. Since Montana is regulated, shopping for a supplier is not an option, so usage is the lever.[/hed_faq]