Home Heating Cost in Illinois (2027): Natural Gas vs Oil vs Electric
Heating costs for your home size in Illinois
Every figure below starts from Illinois's current average energy prices and runs them through the seasonal model behind our heating cost calculator: a Climate Region #2 heating load sized to your home, served by standard mid-efficiency equipment.
In Illinois, a season of heat for 1,700 sq. ft. costs roughly $1,170 at the low end (natural gas) and $4,920 at the high end (electric baseboard heat).
Illinois Heating Cost per Season, Fuel by Fuel
| Fuel & equipment | Price | Season use | Cost / season |
|---|---|---|---|
| Natural gasnatural gas boiler, 82 AFUE | $1.27per therm | 918therms | ~$1,170 |
| Propanepropane boiler, 82 AFUE | $1.83per gal | 1,003gals | ~$1,840 |
| Electric heat pumpductless, ~2.9 COP | $0.230per kWh | 8,839kWh | ~$2,040 |
| Heating oiloil boiler, 82 AFUE | $5.74per gal | 661gals | ~$3,800 |
| Electric baseboardresistance heat | $0.230per kWh | 21,384kWh | ~$4,920 |
Season estimates for a 1,700 sq. ft. home, rounded up to $10, from the same math and rates as our heating cost calculator. Use the buttons to see a drafty or a tight house.
A Season of Heat, Fuel by Fuel
Same house, same winter, five fuels. Hover a bar for the use and the rate behind it.
Season = the modeled Illinois heating load on standard mid-efficiency equipment; fuels ranked like the heating cost calculator (pellet and wood stoves are manual-load and stay unranked).
10-Year Heating Cost Outlook for Illinois
A fuel that wins this winter can lose later if its price climbs faster. The electric lines below rise at Illinois's own electricity trend, about 5.33% a year from 2013 to 2023. For natural gas, heating oil and propane our data has no comparable history, so you choose: hold them at today's price, or let them climb at the electricity pace. Tap or hover any winter to read the numbers.
Season costs at average insulation; winter 1 is today's prices. Totals rounded up to $10.
If natural gas, heating oil and propane stay at today's prices, natural gas costs about $11,650 over 10 winters here, against about $62,790 for electric baseboard heat.
Illinois Climate and Your Heating Load
Winter in Illinois averages about 35°F by day and 19°F by night, which puts it in Region #2 on the map below, one step down from the coldest band. Heating still dominates the energy budget here.
Climate details worth raising with an installer:
Wind. Strong winter wind pushes cold air through every gap in the house: sills, rim joists, attic hatches, outlets. Air sealing is cheap and works on every fuel in the table.
Cold-snap failures. A heating breakdown during a hard freeze can mean burst pipes by morning. A fall tune-up, spare filters and a temperature alert on the thermostat are cheap insurance.
Ice dams. Icicles along the eaves mean heat is leaking into the attic and melting the roof snow from below. Sealing the attic floor and adding insulation stops the leak, which trims the heating bill and the ice at the same time.
Shoulder seasons are the time to shop: spring and early fall. By the first cold week, service calls pile up and quotes come back slower.
Three Things That Change the Number
Up the flue. Going from 82 to 93 AFUE saves about $140 a season on natural gas. Holding on to an aging 62 AFUE unit costs about $380 extra.
Insulation and air sealing. The model moves the load 12% either way: from average to poorly insulated, or from average to well insulated. On natural gas in Illinois, each step is about $140 a season. Try the insulation buttons above the table.
Ductwork. Bare ducts lose about 17% of a furnace's heat in the calculator's duct model. Sealing and insulating them recovers most of it. Boilers and ductless heat pumps have no such loss.
Why the Heat Pump Beats Baseboard
Both electric rows use the same $0.230 per kWh rate. The difference is the machine: resistance heat converts power to heat one for one, while a heat pump gets about 2.5 units of heat per unit of power here, counting the efficiency a heat pump loses in hard cold. The result is about $2,040 a season instead of $4,920. In Illinois it still trails natural gas and propane.
Illinois Heating: Quick Answers
What heats a Illinois house for the least money?
At current rates the winner is natural gas, about $1,170 a season for this house; propane follows at about $1,840. That assumes the home is on a natural gas main.
Should a Illinois home on heating oil convert?
For most homes, yes. This house would spend about $3,800 a season on heating oil and about $1,170 on natural gas, so 10 winters at flat prices leave roughly $26,310 on the table. Weigh that against the conversion quote. That option needs natural gas service at the street.
How much does insulation change the heating bill here?
With natural gas, a poorly insulated 1,700 sq. ft. home costs about $1,310 a season and a well-insulated one about $1,030. That $290 gap repeats every winter.
Pellet and wood stoves can heat cheaply too, but they are manual-load fuels: we price them in the pellet stove calculator and leave them out of the ranking, as the heating cost calculator does.
About these numbers: seasonal estimates from current average Illinois energy rates and a modeled heating load. Use them to compare fuels, not as a quote; real bills follow your winter, your house and your equipment.
