Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Cheaper fuel
Natural Gas
Propane annual cost
$2,273
Natural gas annual cost
$1,040
Annual savings
$1,233
Gas line hookup payback
2.8
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How to use this
- 1Enter annual heating need (million BTU).
- 2Enter propane price ($/gallon).
- 3Enter natural gas price ($/therm).
- 4Enter gas line hookup cost (if none exists) ($).
- 5Read your cheaper fuel on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Propane burns hotter per unit but costs several times more per gallon than natural gas costs per therm, and homes without a gas line have no choice — the real question is whether the higher price per BTU of propane is offset by not paying for a gas line extension. This tool compares annual heating cost using each fuel's price and BTU content, plus optional gas line hookup cost, so you can see the real total and the payback period on installing gas service.
Worked example
Using the values the calculator loads with:
Inputs
- Annual heating need: 80 million BTU
- Propane price: 2.6 $/gallon
- Natural gas price: 1.3 $/therm
- Gas line hookup cost (if none exists): 3500 $
Results
- Cheaper fuel: Natural Gas
- Propane annual cost: $2,273
- Natural gas annual cost: $1,040
- Annual savings: $1,233
- Gas line hookup payback: 2.8
What each field means
Inputs
- Annual heating need (million BTU)
- The annual heating need used in the calculation, measured in million BTU. Starts at 80 million BTU so you have a working example on load.
- Propane price ($/gallon)
- The propane price used in the calculation, measured in $/gallon. Starts at 2.6 $/gallon so you have a working example on load.
- Natural gas price ($/therm)
- The natural gas price used in the calculation, measured in $/therm. Starts at 1.3 $/therm so you have a working example on load.
- Gas line hookup cost (if none exists) ($)
- The gas line hookup cost (if none exists) used in the calculation, measured in $. Starts at 3500 $ so you have a working example on load.
Results
- Cheaper fuel
- Returned as a plain value and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Propane annual cost
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Natural gas annual cost
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Annual savings
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Gas line hookup payback
- Returned as a length of time. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Why is propane usually more expensive per BTU?
Propane must be trucked to a storage tank on your property rather than piped in continuously, adding delivery cost that natural gas utilities spread across a whole pipeline network.
Does propane ever make sense?
Yes — in rural areas without gas lines, propane is often the only practical option, and it burns cleaner than heating oil while heating water and stoves more efficiently than electric resistance.
Should I lock in a propane price contract?
Pre-buy or price-cap contracts before winter can protect against price spikes, but compare the locked rate to recent spot prices before committing for a full season.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Propane vs Natural Gas Heating Cost Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/propane-vs-natural-gas-heating-cost
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/propane-vs-natural-gas-heating-cost" target="_blank" rel="noopener">Propane vs Natural Gas Heating Cost Calculator — RevenueLab</a> (2026).</p>
Source: [Propane vs Natural Gas Heating Cost Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/propane-vs-natural-gas-heating-cost) (2026).