Heat Pump vs Gas Furnace in Montana: 2026 Running Costs
Heating a 2,000 sq ft Montana home costs about $1,811 a year with a heat pump versus $928 with a gas furnace. The heat pump costs about $884 a year more to run than gas — cheap gas and a cold climate is a hard combination to beat.
- Gas is cheaper by
- $884/yr
- running cost
- Heat pump
- $1,811
- per year · COP 2.16
- Gas furnace
- $928
- per year
- Break-even power
- 6.9¢
- per kWh
#41 of 51 states by annual running-cost saving — worse than the national median of -$294/yr. Best is Arkansas at $321/yr. See full rankings.
We would not recommend switching for running-cost savings here.
On the modelled energy prices a heat pump costs about $884 a year MORE to run than a gas furnace in Montana. There may be comfort, cooling or emissions reasons to switch, but the operating-cost case does not stand on its own.
Heat pump vs gas furnace — Montana
Running cost for heating. Adjust anything to see the gap move.
Gas furnace is cheaper to run by
$884
per year · the heat pump never recovers its extra cost here
Heat pump / year
$1,811
13,357 kWh · COP 2.16
Gas furnace / year
$928
1,070 therms
Seasonal efficiency is modelled at COP 2.16 for this climate. Calculators that assume a flat COP of 3 everywhere overstate cold-climate performance — and that is where surprise winter bills come from.
The numbers behind it
| Heating degree days | 8,202 |
|---|---|
| Electricity rate | 13.56¢ / kWh |
| Natural gas price | $0.87 / therm |
| Modelled home size | 2,000 sq ft |
| Annual heat needed | 98.4 million BTU |
| Seasonal COP (modelled) | 2.16 |
| Heat pump electricity | 13,357 kWh |
| Gas used | 1,070 therms |
| Heat pump running cost | $1,811 |
| Gas furnace running cost | $928 |
| Annual difference | $884 for gas |
| Break-even gas price | $1.69 / therm |
| Break-even power price | 6.9¢ / kWh |
| Payback on install premium | Never on running cost |
We would not recommend switching for running-cost savings here.
On the modelled energy prices a heat pump costs about $884 a year MORE to run than a gas furnace in Montana. There may be comfort, cooling or emissions reasons to switch, but the operating-cost case does not stand on its own.
What does a heat pump cost in Montana?
Two different questions get asked with the same words, so here are both, kept apart.
To run — the part we model precisely. Heating a 2,000 sq ft home for a year costs about $1,811 with a heat pump (13,357 kWh at 13.56¢) against $928 with a 92% gas furnace (1,070 therms at $0.87) — a difference of $884 a year in the gas furnace's favour.
To install — the part we deliberately do not claim. We model only the extra cost over a like-for-like furnace replacement, at $4,000, because that premium is what the running-cost difference has to pay back. We do not publish a full installed price for Montana: real quotes turn on ductwork, sizing, electrical capacity and the installer far more than on the state, and we have no dataset that measures it honestly. Anyone quoting you a single statewide installed price is guessing.
The install premium is adjustable in the calculator above, and rebates come straight off it — in several states they cover most of it, which changes the answer more than any modelling choice we make.
Why the honest answer is often “it depends”
A heat pump wins where electricity is cheap relative to gas and the winter is mild enough to keep seasonal efficiency high. It loses where gas is cheap, power is expensive, or the climate is cold enough to drag efficiency down and call on resistance backup. In Montana the balance currently falls in the gas furnace's favour on running cost — but rebates, a dying air conditioner, or a gas price move can each flip that.
How Montana compares nationally
Montana is one of 51 jurisdictions in the same model. The national analysis sets out which side of the line each state falls on and why, along with every assumption, the limitations and a downloadable dataset: heat pump vs gas furnace economics by state.
Common questions
Is a heat pump cheaper than gas heating in Montana?
On running cost alone, no. At 13.56¢ per kWh against gas at $0.87 a therm, a heat pump costs roughly $1,811 a year to run here versus $928 for gas — about $884 a year more. Cheap gas and a cold climate is the combination heat pumps struggle against.
Do heat pumps work in Montana's climate?
They work, but efficiency falls with temperature. At 8,202 heating degree days we model a seasonal COP of 2.16 — roughly 2.2 units of heat per unit of electricity across the season, not the 3+ that mild-climate marketing implies.
How long does a heat pump take to pay for itself in Montana?
It doesn't, on running cost alone — it costs more to run here, so the extra install cost never comes back through the energy bill. The case rests on rebates, replacing a dying air conditioner at the same time, or reasons other than money.
What electricity price would make a heat pump worthwhile in Montana?
Below about 6.9¢ per kWh, holding gas at $0.87 a therm. Montana averages 13.56¢, which is above that line. Equivalently, gas would need to reach $1.69 a therm for the two to level at today's power price.
Does this include air conditioning?
No, and that matters. A heat pump is also an air conditioner, so if you were replacing a failing AC anyway, the true extra cost is much lower than the figure used here — sometimes near zero. This compares heating running costs only.
How we calculate this
Annual heat demand comes from heating degree days and a modelled building heat-loss rate, then met two ways: a gas furnace at 92% efficiency, and a heat pump at a seasonal COP derived from the local climate.
That climate-varying COP is the part most calculators skip. Applying one flat efficiency everywhere assumes a mild winter in a cold state, and is the single biggest reason published heat pump savings often fail to appear on real bills.
Excluded: cooling benefit, rebates and incentives, maintenance differences, and any electrical panel upgrade. Analysis horizon 15 years.
Data vintage: Electricity: EIA Electric Power Monthly Table 5.6.B (residential, May 2026 YTD). Solar resource: PVGIS v5.3 (EU JRC), ERA5 2005-2023. Gasoline: AAA state averages. Natural gas: EIA residential by state. Heating degree days: NOAA CPC population-weighted normals. Residential consumption: EIA Electric Sales, Revenue, and Average Price Table 5.A, average monthly kWh per residential customer, 2024. Vehicle miles: FHWA Highway Statistics 2023. Retrieved 2026-08-03/04 and 2026-08-21. Install costs, net-metering status, time-of-use spreads and outage hours remain estimates.
How Montana compares
| # | State | Annual running-cost saving |
|---|---|---|
| 1 | Arkansas | $321/yr |
| 2 | Georgia | $273/yr |
| 3 | Washington | $200/yr |
| 4 | Arizona | $155/yr |
| 5 | Texas | $155/yr |
| 6 | Louisiana | $144/yr |
| 7 | North Carolina | $130/yr |
| 8 | Missouri | $126/yr |
| 9 | Florida | $118/yr |
| 10 | Alabama | $114/yr |
Computed from the same model as this page. Full national findings · how this is calculated · data sources