How much does an electric furnace cost to run?

Residential electric furnaces range from 10,000 to 30,000 watts. The most common sizes for a single-family home fall between 15,000 and 20,000 watts. The Goodman MBR series runs 20,000 watts. Rheem's RH1T sits at 15,000. First Company's 24HBXB-HW pushes 24,000. Larger homes or poorly insulated older construction sometimes need 30,000 watts or more.

Those are nameplate numbers. Your electric meter sees less because the furnace cycles on and off as the thermostat calls for heat. When indoor temperature reaches the set point, the heating elements shut down and only the blower continues at 300 to 500 watts. When the temperature drops below the set point, the elements fire again. In a well-insulated home on a 35°F day, the elements may only run 30 to 40% of the time the furnace is active. During a 10°F cold snap, that duty cycle climbs toward 70 to 80% because the house loses heat faster than the furnace can replace it.

The electric furnace calculator page uses a 40% duty cycle as the typical seasonal average. That accounts for the mix of mild days, cold snaps, and overnight setbacks that make up a real heating season. The monthly cost figures below all use that 40% average unless noted otherwise.

State electricity rates turn the same furnace into completely different bills. A 20,000-watt unit running eight hours a day at 40% duty cycle uses 1,920 kWh per month. At current 2026 residential rates:

Louisiana at 11.9¢/kWh: $228 per month. Texas at 14.8¢: $284. National average at 18.05¢: $347. New York at 22.3¢: $428. Connecticut at 28.7¢: $551. California at 31.4¢: $603.

A milder month with only three hours of daily run time cuts all those figures by roughly 60%. That brings the national average down to $130 and Louisiana to $86. Over a five-month heating season, the total depends on how those months break down. A typical pattern in the mid-Atlantic: October at 3 hours a day ($130 at the national average), November and March at 5 hours ($217 each), December and January at 8 hours ($347 each). That's $1,258 for the season at the national average. In Minnesota with heavier December through February use, the same furnace runs closer to $1,800. In coastal South Carolina with a shorter, milder winter, $600 to $800. The full state-by-state rate breakdown covers all 50 states and DC with current 2026 residential rates.

A gas furnace uses electricity only for the blower motor and controls. The Carrier Infinity 98 draws 480 watts. Trane's S9V2 uses 550. Lennox's SLP98V pulls 500. That's the entire electrical load. Natural gas provides the actual heat.

Running the blower eight hours a day uses about 4 kWh, or $0.72 at the national average rate. That's $22 per month in electricity. Add the natural gas bill, which varies by region but typically runs $60 to $120 per month for winter heating, and a gas furnace costs $80 to $140 total to operate per month.

An electric furnace doing the same heating job costs $260 to $350 per month in electricity alone. No gas line, no gas bill, but the total operating cost runs two to three times higher. The gap widens in high-rate states: a gas furnace in Connecticut costs roughly $120 to $160, while the electric furnace costs $551.

Electric furnaces exist in homes for three reasons. The house has no natural gas service, which is common in rural areas and parts of the Southeast. The furnace serves as backup for a heat pump, providing resistance heat only when outdoor temperatures drop below the heat pump's effective range. Or the home is in a mild climate where the furnace runs so few hours per year that the lower installation cost of electric (no gas line, no flue, no venting) outweighs the higher operating cost.

The DOE rates electric furnaces at 95 to 100% AFUE (Annual Fuel Utilization Efficiency). Every watt the heating elements consume becomes heat. There are no combustion losses, no flue gases, no wasted energy going up a chimney.

The problem is the fuel, not the machine. Electricity at 18.05¢/kWh delivers heat at roughly $52.90 per million BTU. Natural gas at $1.20 per therm delivers heat at about $14 per million BTU after accounting for a 96% AFUE gas furnace. The DOE's electric resistance heating page states the same conclusion: electric resistance is the most expensive form of heating in most of the country, despite being technically the most efficient at converting its input to heat.

A heat pump moves heat from outdoor air into the house instead of generating it from scratch. Modern cold-climate models (Mitsubishi Hyper-Heating, Daikin Fit, Bosch IDS 2.0) work effectively down to -15°F. Their coefficient of performance (COP) of 2 to 3 means they deliver two to three times as much heat per watt as electric resistance coils.

In practical terms, a heat pump doing the same heating work as a 20kW electric furnace uses 7,000 to 10,000 kWh per season instead of 15,000 to 20,000. At the national average rate, that's $800 to $1,500 in annual savings. The upfront cost is higher ($8,000 to $15,000 installed versus $2,000 to $4,000 for an electric furnace), but the operating savings pay back the difference in three to seven years depending on your rate and climate.

If a heat pump isn't in the budget, the cheapest improvement is sealing the building envelope. Electric furnaces punish leaky homes harder than any other heating system because every BTU of lost heat gets replaced at electricity prices. Air sealing and attic insulation can cut heating costs 20 to 40% according to the DOE. Their air sealing guide covers where homes lose the most heat and how to fix it.

A heat pump is the long-term answer, but three changes reduce costs this winter without any capital outlay. First, lower the thermostat. The DOE estimates that every degree below 70°F saves 2 to 3% on heating costs. Setting the thermostat to 66°F during the day and 60°F overnight can cut a $347 monthly bill to $260 to $290.

Second, heat the room you're in instead of the whole house. A 1,500-watt space heater costs $0.27 per hour at the national average rate. The electric furnace at 20,000 watts and 40% duty costs $1.44 per hour. If you spend most of the evening in one room, turning down the thermostat and running a space heater in that room costs less than heating the entire house.

Third, replace the furnace filter on schedule. A clogged filter forces the blower motor to work harder, which increases electricity use and makes the heating elements run longer to push the same amount of heat into the house. A $15 MERV 11 filter replaced every 90 days costs $60 a year and prevents the 5 to 15% efficiency penalty that dirty filters create.

Furnace wattage, daily run hours, and your state rate all change the monthly cost. Enter your numbers in the calculator below. For a cold-snap estimate, use 8 to 10 hours per day. For an average winter day, 4 to 6.

The electric furnace sits at the top of the most expensive appliances ranking. If your winter bill spiked and the source isn't clear, the high-bill diagnostic walkthrough covers how to isolate which appliance is driving the increase.