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Heating Cost Blog

Updated February 2026 · 7 min read

Propane and natural gas are both popular heating fuels, but they are not interchangeable — and the cost difference between them can be substantial. If you are building a new home, converting from one fuel to another, or simply trying to understand your heating bills, this head-to-head comparison covers everything you need to know about propane vs natural gas heating costs in 2026.

The short answer: natural gas is almost always cheaper than propane for home heating. At 2026 national average prices, natural gas costs about $12 per million BTU delivered, while propane costs about $32 — roughly 2.5 times more. But availability often dictates the choice: if your home does not have access to a natural gas line, propane may be your best gas-fired option.

BTU Content: Propane vs Natural Gas

To compare these fuels fairly, you need to understand the energy content of each:

PropertyPropaneNatural Gas
BTU per unit91,500 BTU/gallon100,000 BTU/therm
Common unitGallonsTherms or CCF
Delivery methodTruck to on-site tankUnderground pipe
Storage requiredYes (above/below ground tank)No (on demand)

One gallon of propane contains 91,500 BTU of energy. One therm of natural gas contains 100,000 BTU. So on a raw energy basis, a therm of natural gas contains about 9% more energy than a gallon of propane. But the real cost difference comes from the price per unit, not the BTU content.

Efficiency: Both Fuels Are Similar

Both propane and natural gas furnaces are available in the same efficiency ranges, because both burn in virtually identical equipment. The AFUE (Annual Fuel Utilization Efficiency) ratings break down as follows:

Because the efficiency ratings are the same for both fuels, the cost comparison boils down to a straightforward question: how much does each fuel cost per BTU?

Price Comparison: National Averages

At 2026 national average prices, the cost difference is stark:

MetricPropaneNatural Gas
Average unit price$2.60/gallon$1.10/therm
BTU per unit91,500100,000
Cost per raw million BTU$28.42$11.00
Cost at 80% AFUE ($/MMBTU delivered)$35.52$13.75
Cost at 92% AFUE ($/MMBTU delivered)$30.89$11.96
Cost at 96% AFUE ($/MMBTU delivered)$29.60$11.46

Source: U.S. Energy Information Administration (EIA), residential average prices

Even with a high-efficiency propane furnace (96% AFUE) compared against a standard natural gas furnace (80% AFUE), natural gas is still more than twice as cheap — $13.75 vs $29.60 per million BTU delivered. Upgrading your propane furnace to high efficiency helps, but it cannot close the gap.

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State-by-State Comparison

National averages mask significant regional variation. The table below shows propane and natural gas prices in select states along with the resulting cost per million BTU (assuming a 92% AFUE furnace for both).

StatePropane $/galGas $/thermPropane $/MMBTUGas $/MMBTU
Texas$2.15$0.85$25.53$9.24
Ohio$2.20$0.95$26.13$10.33
Minnesota$2.10$0.90$24.93$9.78
Pennsylvania$2.75$1.15$32.66$12.50
New York$3.10$1.40$36.81$15.22
Virginia$2.50$1.10$29.69$11.96
Michigan$2.35$0.90$27.91$9.78
North Carolina$2.70$1.20$32.07$13.04
Wisconsin$2.15$0.88$25.53$9.57
Connecticut$3.30$1.65$39.18$17.93

Source: U.S. Energy Information Administration (EIA), state-level residential prices. Cost per MMBTU assumes 92% AFUE furnace.

In every state listed, natural gas is significantly cheaper than propane — typically 2 to 2.8 times cheaper. The gap is narrowest in states like Minnesota and Wisconsin where Midwest propane prices are relatively low, and widest in the Northeast where propane prices are highest.

When Propane Makes Sense Despite the Cost

Given the cost disadvantage, why do roughly 5 million American households heat with propane? The answer is almost always availability:

If your home currently heats with propane and you have access to a natural gas line, switching to natural gas is one of the highest-return home energy upgrades you can make. The conversion typically costs $2,000-$5,000 (for a new gas furnace and hookup) and can save $1,500-$3,000 per year in heating costs, paying for itself in one to three seasons.

Propane vs Natural Gas: Beyond Operating Cost

Cost per BTU is the most important factor, but there are other considerations:

Safety

Both fuels are safe when properly installed and maintained. One key difference: natural gas is lighter than air and rises when it leaks, while propane is heavier than air and pools at ground level. Both have odorants added (mercaptan) so leaks can be detected by smell. Propane tanks require periodic inspection, while natural gas has no on-site storage to maintain.

Environmental Impact

Natural gas produces about 117 pounds of CO2 per million BTU. Propane produces about 139 pounds per million BTU. Both are cleaner than heating oil (163 lbs/MMBTU). On a per-BTU-delivered basis, natural gas has a lower carbon footprint — and because it costs less, you are also likely to use a more efficient system.

Price Volatility

Propane prices are more volatile than natural gas, especially in winter. Cold snaps can cause propane prices to spike 50% or more in a matter of weeks because supply depends on truck deliveries and regional storage. Natural gas prices are more stable because the pipeline system provides continuous supply. Propane users can manage volatility by filling their tank in summer when prices are lower or by locking in a price with their supplier for the heating season.

Equipment and Maintenance

Propane and natural gas furnaces are very similar. In many cases, a furnace can be converted from one fuel to the other by swapping the burner orifices and adjusting the gas valve — a job that typically costs $150-$500 for a technician. Boilers, water heaters, and gas fireplaces can also be converted. Maintenance requirements are essentially identical for both fuels.

Should You Switch Fuels?

See how much you could save by switching from propane to natural gas — or to a heat pump — with real prices for your state.

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What About Heat Pumps as an Alternative?

If you heat with propane and do not have access to natural gas, a heat pump may be a better alternative than staying with propane. At the national average electricity price of $0.165/kWh, a heat pump with COP 3.0 delivers heat for about $16 per million BTU — roughly half the cost of propane.

In states with cheap electricity (the Pacific Northwest, parts of the Southeast), the savings are even larger. Even in states with moderate electricity prices ($0.14-$0.18/kWh), a heat pump typically beats propane by 40-60%. The main exception is very cold climates where heat pump efficiency drops significantly, though modern cold-climate models have narrowed that gap considerably.

The Inflation Reduction Act offers up to $8,000 in heat pump rebates for qualifying households, which can make the switch from propane to a heat pump financially compelling even in colder regions.

How to Reduce Your Propane Costs

If you are stuck with propane and switching is not an option, these strategies can reduce your bills:

  1. Upgrade to a high-efficiency furnace. Going from 80% to 96% AFUE saves 17% on fuel. At $2,500/year in propane costs, that is $425/year in savings.
  2. Pre-buy propane in summer. Propane is cheapest from June through September. Many suppliers offer pre-buy or locked-price contracts that protect against winter spikes.
  3. Shop multiple suppliers. Propane prices are not regulated, and quotes can vary by $0.30-$0.50/gallon between companies. Get at least three quotes before each fill.
  4. Improve insulation and air sealing. Reducing heat loss means buying fewer gallons. Attic insulation and air sealing typically pay for themselves in 2-3 years.
  5. Use a programmable thermostat. Setbacks of 5-8 degrees during sleep and away times can reduce consumption by 10-15%.
  6. Supplement with a heat pump. A ductless mini-split in your most-used living area can handle moderate days while the propane furnace covers the coldest nights. This hybrid approach can cut propane use by 30-50%.

The Bottom Line

Natural gas is consistently and significantly cheaper than propane for home heating — about 2.5 times cheaper per BTU delivered at 2026 prices. This is true in every state where both fuels are available.

The decision tree is straightforward:

  1. If you have access to natural gas: Use it. It is the cheapest gas heating option, period.
  2. If you currently heat with propane and gas is available nearby: The conversion typically pays for itself within 1-3 heating seasons.
  3. If you heat with propane and gas is not available: Consider a heat pump as an alternative — it is likely cheaper than propane in your area, especially with IRA rebates.
  4. If you must stay with propane: Upgrade efficiency, pre-buy fuel in summer, and shop suppliers aggressively.

For a personalized cost comparison using your state's actual energy prices, use our free heating cost calculator. It compares propane, natural gas, heat pumps, and seven other heating options side by side.

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