# Propane vs heat pump: which costs less to run? > A heat pump costs less to run than a propane furnace whenever its efficiency, the heat it delivers per unit of electricity, beats a break-even set by your electricity and propane prices. At EIA's national averages for March 30, 2026 propane and January-June 2026 electricity, that break-even is about 1.7, which an ENERGY STAR heat pump clears over a standard season, while ENERGY STAR's cold-climate minimum at 5°F, a COP of 1.75, only roughly matches it. _Updated Oct 12, 2026._ A heat pump costs less to run than a propane furnace whenever it delivers more heat per unit of electricity than a break-even ratio set by two prices: what you pay per kilowatthour and what you pay per gallon. At the EIA national figures in the worked example below, that ratio is about 1.7, but it moves a long way by region, with the weather and as prices change. ## Put both fuels on the same footing A gallon of propane holds 91,452 Btu and a kilowatthour of electricity holds 3,412 Btu, per EIA's conversion factors. A household pays for heat in the rooms, so each fuel's energy is multiplied by its appliance's efficiency. For a propane furnace that efficiency is its AFUE, the share of the fuel's energy delivered as heat over a season. The Department of Energy's federal purchasing requirement for home furnaces, which covers natural gas, propane and oil models alike, is 95 percent AFUE in northern states and 90 percent in southern ones. At 95 percent, every $1.00 per gallon of propane works out to about $11.51 per million Btu (MMBtu) of delivered heat. A furnace at 80 percent AFUE gets about 16 percent less heat from the same gallon. A heat pump's efficiency is its coefficient of performance, or COP: heat delivered divided by electricity consumed. Because a heat pump moves heat from outdoors rather than making it, its COP runs above 1, while electric baseboard heat sits at exactly 1. Every cent per kilowatthour works out to about $2.93 per MMBtu of heat at a COP of 1, and that cost falls in proportion as COP rises. ## The break-even in one line Divide one conversion by the other and the comparison collapses to a single number. A heat pump matches a 95 percent propane furnace on running cost when: **Break-even COP = electricity price in cents per kWh ÷ (3.93 × propane price in dollars per gallon)** Above that COP the heat pump delivers heat for less; below it the propane furnace does, and the formula works with the prices on any pair of bills. ## Worked example: three regions, one formula [Table: United States propane price](https://fill-line.com/region/us) ([data](https://fill-line.com/region/us.md)) The table above carries the national residential propane price, which EIA surveys weekly from October through March. The worked example uses the last reading of the 2025-26 season, $2.674 a gallon in the week of March 30, 2026. EIA's Electric Power Monthly puts the average US residential electricity price at 18.16 cents per kWh for January through June 2026. Run the numbers: - **United States:** propane heat costs $30.78 per MMBtu and electric resistance heat $53.22. The break-even COP is 1.73. - **New England:** propane at $3.766 on [the PADD 1A price page](/region/padd1a) and electricity at 29.04 cents put propane heat at $43.35 and resistance heat at $85.11, for a break-even COP of 1.96. - **Midwest:** propane at $2.184 on [the PADD 2 price page](/region/padd2) puts propane heat at $25.14. PADD 2 spans two census divisions with very different power prices: 18.96 cents in the East North Central states and 14.16 cents in the West North Central states, for break-even COPs of 2.21 and 1.65. For scale, ENERGY STAR's minimum for a split-system heat pump is an HSPF2 of 7.8. HSPF2 counts Btu of heat per watthour of electricity across a standard test season, so dividing by 3.412 converts it to a seasonal COP of about 2.3. At that COP, heat pump heat costs $23.28 per MMBtu nationally, $37.23 in New England, $24.31 in the East North Central states and $18.15 in the West North Central states. The propane figures to set against them are $30.78, $43.35 and, for both Midwest divisions, $25.14. The Midwest gap is the one that splits: 83 cents per MMBtu in the East North Central states and nearly $7 in the West North Central states. These inputs are regional averages from different stretches of the year, a late-March propane survey against a January-through-June electricity average, and neither is anyone's actual bill. Tiered or time-of-use electric rates, a propane contract price or a tank rental all change the inputs. The formula does not change. ## Why the answer changes with the weather A heat pump's COP is not fixed. It falls as the outdoor temperature drops, which is why ENERGY STAR tests heat pumps at 5°F as well as in milder conditions. Its cold-climate label requires a COP of at least 1.75 at 5°F, with at least 70 percent of the unit's rated heating capacity still available. That 1.75 sits right at the national break-even of 1.73 and below the New England and East North Central figures. [Chart: US heating degree days (propane-weighted)](https://fill-line.com/heating-demand/us) ([data](https://fill-line.com/heating-demand/us.md) — chart image: https://fill-line.com/charts/heating-demand/us/chart.png) The weeks that pile up the most heating degree days on the chart above are the weeks a heat pump runs at its lowest COP, and the weeks a house burns the most energy of any kind. That is the logic of a dual fuel system, which pairs a heat pump with a furnace that takes over in the coldest weather. ENERGY STAR describes dual fuel systems as a way to use each system where it works best on cost, and notes that below 5°F even a cold-climate heat pump heats most efficiently with a backup source. With propane as the backup fuel, the cost crossover is the outdoor temperature at which the heat pump's COP falls to the break-even worked out above. ## What the arithmetic leaves out This is running cost only. Equipment and installation prices, the cooling a heat pump also provides, tank arrangements and what either fuel will cost next winter all sit outside the calculation, and The Fill Line does not forecast any of them. Propane's own price moves through the heating season, as [why propane prices rise in winter](/guides/why-propane-prices-rise-in-winter) explains, and a propane-heated home's seasonal gallons are laid out in [how much propane a home uses](/guides/how-much-propane-does-a-home-use). The [heating fuel cost comparison calculator](/tools/fuel-cost-comparison) below runs the same conversion with your own prices and efficiencies. The Fill Line is a free weekly read of the public propane numbers: the state price survey from October through March, and stocks, the Mont Belvieu spot and the weekly supply balance year round. One email a week on what moved. ## Related data + guides - [Heating fuel cost comparison calculator](https://fill-line.com/tools/fuel-cost-comparison) - [US residential propane price](https://fill-line.com/region/us) - [New England (PADD 1A) propane price](https://fill-line.com/region/padd1a) - [Midwest (PADD 2) propane price](https://fill-line.com/region/padd2) - [US propane-weighted heating degree days](https://fill-line.com/heating-demand/us) - [How much propane does a home use?](https://fill-line.com/guides/how-much-propane-does-a-home-use) - [Why propane prices rise in winter](https://fill-line.com/guides/why-propane-prices-rise-in-winter) ## Common questions ### Is a heat pump cheaper to run than propane? It depends on two local prices and the heat pump's efficiency. A heat pump delivers heat for less than a 95 percent propane furnace when its COP is above the electricity price in cents per kWh divided by 3.93 times the propane price per gallon. At the EIA national averages in the worked example, 18.16 cents (January-June 2026) and $2.674 (March 30, 2026), that break-even is about 1.7, below the seasonal COP of about 2.3 implied by ENERGY STAR's HSPF2 minimum of 7.8 but close to the 1.75 a cold-climate unit must reach at 5°F. ### How do you compare propane and electric heating costs? Convert both to dollars per million Btu of delivered heat. For propane, divide the price per gallon by 0.091452 (million Btu per gallon) and by the furnace's AFUE. For electricity, divide the price per kWh by 0.003412 and by the heat pump's COP, or by 1 for baseboard heat. The lower result is the cheaper heat at those prices. ### Do heat pumps work in cold weather? Cold-climate models keep working below 5°F, per ENERGY STAR, but a heat pump's efficiency falls as the temperature drops. ENERGY STAR's cold-climate designation requires a COP of at least 1.75 at 5°F, with at least 70 percent of rated heating capacity available at that temperature, and ENERGY STAR notes that below 5°F, pairing one with a backup heat source heats a home most efficiently. ### What is a dual fuel heat pump? A heating system that pairs a heat pump with a fuel-burning furnace and switches between them. The heat pump carries the mild weather and the furnace takes over in the coldest stretches. With a propane furnace, the running-cost crossover is the outdoor temperature at which the heat pump's COP falls to the break-even set by local electricity and propane prices. --- Canonical URL: https://fill-line.com/guides/propane-vs-heat-pump