Heating Fuel Cost Calculator
Enter your fuel prices and equipment efficiency — compare oil, propane, natural gas, heat pumps, firewood, and pellets in dollars per million BTU of delivered heat, side by side. Edit every default: the honest version of this tool is your numbers, not national averages.
What this tells you:
The three numbers that matter
Every estimate here is price ÷ (energy per unit × efficiency). The energy constants come from government fuel tables: heating oil 138,500 BTU/gal, propane 91,333 BTU/gal, natural gas 100,000 BTU/therm, electricity 3,412 BTU/kWh (NH DOE and DOE figures, Sept 2026). The defaults are dated: oil $5.10/gal and electricity 18.20¢/kWh are EIA's September 2026 national projections, propane $2.67/gal is EIA's final weekly average of the 2025–26 heating season, and gas $1.26/therm is New Hampshire's September 2026 residential price. Fuel prices move by region and season, so the editable fields are the honest version of this tool: plug in your contract rate or your last bill.
The punchline the cornerstone guide lands on: at those dated prices, oil heat costs roughly $43 per million BTU delivered, a heat pump at a COP of 2.5 costs roughly $21, and resistance electric heat costs roughly $53. Firewood looks like the winner at $16 — until you price your labor.
Honest limits
- Defaults are dated, not quotes. Oil and propane prices swing hard by region and season; weekly EIA reporting resumes each October. If you are budgeting for winter, use your supplier's locked price.
- Efficiency is doing half the work. An oil furnace at 83% vs. 89% AFUE is a 7% swing in delivered cost on the same fuel. Use your equipment's real AFUE or COP — it is on the nameplate or in the manual.
- Firewood is priced at bought wood. Cut-your-own is not free once you count equipment, fuel, and hours. A cord at $0 with 12 hours of labor behind it is a hobby, not a heating plan.
- Pellet energy density is a trade figure. The 8,200 BTU/lb default comes from trade and manufacturer specs; the U.S. has no mandatory pellet-fuel standard. The corroborated range is 8,000–8,700.
- Operating cost is not total cost. The $/MMBTU ranking ignores equipment price, maintenance, and delivery fees — all real, all different by system. The equipment-cost table in the guide covers the other half.
Where every number comes from
No invented numbers. BTU constants are NH Dept. of Energy and DOE fuel-table figures (oil 138,500/gal, propane 91,333/gal, gas 100,000/therm, electricity 3,412/kWh); firewood MMBTU/cord is UMD Extension species data with an editable default of 22; pellet BTU/lb is trade-sourced with an editable default of 8,200. Price defaults are dated EIA and NH DOE figures, published in our home heating guide.
Frequently asked questions
Why does efficiency change the ranking so much?
Because $/MMBTU is price divided by (energy × efficiency), and efficiency varies more than people expect. A heat pump at COP 2.5 delivers two and a half times the heat per dollar of electricity as baseboards on the same rate — that is the whole reason heat pumps beat oil on operating cost even where electricity is not cheap.
What should I enter for my annual heating load?
Work backwards from last winter's fuel bills: units burned × BTU per unit × your system's efficiency, in millions. A home that burned 800 gallons of oil at 85% used about 94 MMBTU. That one number turns the $/MMBTU ranking into an annual dollar comparison.
Why is my propane number so different from the default?
Regional swing. The $2.67 default is EIA's national average from the final week of the 2025–26 heating season; New Hampshire was at $4.02 in September 2026. Propane is the most regionally variable fuel on this page — your contract price is the only one that matters.
Does this account for the cost of the equipment?
No — deliberately. This tool answers "what does each fuel cost to run," not "what should I buy." Equipment costs are in the guide's cost table: roughly $4,000–$10,000 for an oil furnace, $2,200–$8,000 for propane, $2,000–$16,000 for ductless by zone, $8,000–$18,000 for a ducted heat pump.
Which firewood energy value should I use?
It depends on species and moisture. UMD Extension puts seasoned hardwood at roughly 25–29 MMBTU/cord (white oak 27, sugar maple 25), pine around 19, cottonwood around 16 — all at ~20% moisture. The 22 default is a reasonable mixed-hardwood middle; drop it if you burn softwood, and never trust a number for green wood.
Want the full picture? Read how home heating works for rural homes.