CostToRunIt

Heating & Cooling · West

Cost to run a heat pump in Montana

At Montana’s average residential rate of 14.67¢ per kWh, a heat pump drawing 2400W for 10 hours a day costs about $64.30 a month. Change the numbers below to match how you actually use yours.

Heating is the dominant load in Montana, and the cold is sustained rather than intermittent, so a heat pump here runs at high duty for months at a stretch rather than in short bursts. The annual figure below is the one that matters; the daily figure understates what a Montana winter actually costs.

Quick answer

Per hour$0.2111.440 kWh
Per day$2.1114.40 kWh
Per month$64.30438.3 kWh
Per year$7715,256 kWh

Based on 2400W at a 60% duty cycle (this equipment cycles on and off rather than drawing full power continuously) and 14.67¢/kWh, the Montana average for May 2026.

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Why the cost differs in Montana

Montana has the 13th cheapest residential electricity of the 51 US states and territories we track, at 14.67¢ per kWh against a national average of 18.44¢. That is -20.4% compared with the national figure. Montana combines hydroelectric and wind generation with the lowest population density outside Alaska and Wyoming, which cuts both ways: cheap generation, but long transmission runs to few customers. Retail service is largely regulated. Winter heating dominates by a wide margin, and the heating season is long enough that space heating choices matter more here than almost anywhere.

For this appliance specifically, the difference works out to a saving of $198 a year against what the same heat pump would cost at the national average rate. Run the identical appliance in Hawaii and it would cost $2,733 a year; in Idaho it would cost $649. That spread of $2,084 is entirely down to location.

At Montana's rate this single heat pump accounts for roughly 50% of a typical household's entire annual electricity bill. It is not a rounding error on your statement - it is one of the largest single line items in it.

Montana sits below the national average, so this heat pump costs slightly less to run here than it would for a typical US household. How you use it will move the number far more than where you live.

Retail service in Montana is regulated, so most households pay a tariff set through state rate cases rather than a shopped rate. The state average is a reasonable proxy, though your utility's specific tariff still varies.

Annual cost of this heat pump at different rates
LocationRatePer monthPer year
Montana this page 14.67¢ $64.30 $771
US average 18.44¢ $80.83 $969
Idaho cheapest state 12.35¢ $54.13 $649
Hawaii most expensive 52.00¢ $228 $2,733

Montana electricity rate trend

Rates in Montana have moved from 14.81¢ to 14.67¢ per kWh over the last twelve months of published data. Nationally, residential rates rose about 6.2% year over year.

2025-06 to 2026-05 · cents per kWh

About running a heat pump

A heat pump moves heat rather than generating it, delivering two to four units of heat per unit of electricity. In cold snaps below its balance point it falls back on resistance backup strips, which draw far more - this is why heat pump bills spike in extreme cold rather than scaling smoothly.

What actually changes the cost

  • Nameplate wattage is not running cost. This heat pump draws about 2400W when active, but cycles roughly 60% of the time it is switched on, so effective consumption is near 1440W.
  • At typical use this is a major load - around 5,256 kWh a year. Efficiency upgrades here pay back faster than on any small appliance.
  • Models vary widely, from about 1500W to 4000W. Check the nameplate on your own unit rather than assuming an average, because the spread is more than 2x.
  • Insulation and air sealing reduce runtime, which lowers cost more reliably than adjusting the thermostat by a degree.
  • If your utility offers time-of-use pricing, shifting this load off-peak can cut its cost substantially without using any less energy.

How we worked this out

The arithmetic is simple and we would rather show it than hide it. Divide watts by 1,000 to get kilowatts, multiply by hours of use and by the duty cycle to get kilowatt-hours, then multiply by your rate:

2400W ÷ 1000 × 10h × 60% = 14.400 kWh/day × 14.67¢ = $2.112 per day

One honest caveat: Montana’s figure is a state average published by the EIA. Your own utility’s tariff, any time-of-use pricing, fixed monthly service charges and local taxes all shift the real number. Put your actual per-kWh rate into the calculator above for a figure that reflects your bill.

Questions about heat pump running costs

How many watts does a heat pump use?

A typical heat pump draws about 2400 watts while running, with most models falling between 1500W and 4000W. Check the nameplate label or manual for your specific unit - the range is wide enough that averages can mislead.

How much electricity does a heat pump use per day?

At around 10 hours of use a day and a 60% duty cycle, that works out to roughly 14.4 kWh per day, or about 432 kWh a month. Your actual figure depends on your usage and model.

Why does the cost differ so much between states?

Residential electricity rates across the US range from about 12.35 cents per kWh in North Dakota to 46.62 cents in Hawaii - nearly a fourfold difference. The same heat pump, used identically, therefore costs almost four times as much to run in the most expensive state as in the cheapest.

Is it cheaper to run a heat pump at night?

Only if you are on a time-of-use or variable tariff. On a flat rate, the time of day makes no difference to cost. If you are on time-of-use pricing, off-peak hours are typically materially cheaper, and shifting this load can reduce its cost without reducing usage.