Heating Oil for a Season Calculator: Gallons, Cost and Tank Fills
Estimate the gallons of heating oil and the cost of a whole heating season from your home’s heat load or your burner nozzle size, with furnace efficiency, 2026 oil prices, tank fills, cost per million BTU and a price and efficiency comparison.
How it works
Heat load: season heat = heat load × hours per day × days; gallons = season heat ÷ (BTU per gallon × AFUE) · Burner nozzle: gallons = nozzle GPH × burner hours per day × days · Cost = gallons × price · Tank fills = gallons ÷ tank size · CO₂ = gallons × 22.45 lb
Heating oil holds about 137,381 BTU per gallon (EIA’s 2026 figure for ultra-low-sulfur heating oil; the older No. 2 figure is 138,500), but only the AFUE share of that reaches your rooms; the rest goes up the flue. With the heat-load method, multiply the home’s average heat load by the hours a day it needs that heat and by the days in the season, then divide by the usable heat in a gallon. With the burner-nozzle method, the nozzle’s gallons-per-hour rating times the hours the burner actually fires gives the oil burned directly, and the efficiency tells you how much of it becomes heat. The cost uses your price per gallon; the default is EIA’s U.S. average residential price for the week of 19 October 2026, $6.19 a gallon before tax. The results also show how many times you would fill your tank, the cost per million BTU of delivered heat (handy for comparing with propane, gas or a heat pump), and the carbon dioxide released, at EIA’s 22.45 lb of CO₂ per gallon. Real use tracks the weather, the thermostat setting and the insulation, so a mild winter can come in under this estimate and a harsh one over it.
Worked example
A 30,000 BTU/hr heat load for 14 hours a day over 150 days is 30,000 × 14 × 150 = 63.0 million BTU. At 85% AFUE each gallon delivers 137,381 × 0.85 = 116,774 BTU, so the season needs 63,000,000 ÷ 116,774 = 540 gallons. At $6.19 a gallon that is about $3,340 for the season, or about $668 a month over 5 months, and nearly 2 fills of a 275-gallon tank.
Sources: EIA: Heating Oil and Propane Update (weekly residential prices) · EIA: Weekly heating oil and propane prices, residential No. 2 heating oil · EIA: Energy conversion calculators (heating oil 137,381 Btu per gallon, 2026) · EIA: Carbon dioxide emissions coefficients (22.45 lb CO₂ per gallon of heating fuel) · InspectAPedia: Heating oil consumption rate (nozzle GPH rating)
Frequently asked questions
How many gallons of heating oil does a house use in a winter?
A northern single-family home commonly burns roughly 500 to 800 gallons in a heating season, depending on its size, insulation, thermostat setting and the winter. Enter your heat load or nozzle size and run hours to estimate your own home.
How do I estimate oil use from the burner nozzle?
The number stamped on the nozzle is its firing rate in gallons per hour (GPH) at standard pump pressure. Multiply it by the hours the burner actually runs. A 0.85 GPH nozzle firing 6 hours a day burns about 5.1 gallons a day, or 153 gallons a month.
How big is a typical home heating-oil tank?
The most common size is 275 gallons. Tanks are not run empty, so each delivery adds less than the full size, and many homes refill two or three times over a cold winter.
Does a higher-AFUE furnace really cut my bill?
Yes, roughly in proportion. Going from an old 70% unit to a modern 87% one cuts oil use by about 1 − 70/87 ≈ 20% for the same heat. The efficiency table shows the gallons and cost for your home at each efficiency.
How much does heating oil cost in 2026?
The U.S. Energy Information Administration reported an average residential price of $6.19 a gallon (before tax) for the week of 19 October 2026, about $2.66 more than a year earlier. Prices differ by state and dealer, so enter your own quote.
Related calculators
This is an estimate for budgeting. Actual oil use and prices depend on the weather, your equipment and your dealer.