Space Heater Cost Calculator

Find out what an electric space heater costs to run per hour, per day, per month and over a whole winter at your electricity rate.

Your heater

Heater setting
Use

Every electric space heater turns 1 kWh into 3,412 BTU of heat. Ceramic, oil-filled and infrared models of the same wattage cost the same to run.

What it costs

Per hour
–
while running
Per month
–
Per season
–

Monthly cost at other electricity rates

RatePer dayPer month

How much does it cost to run a space heater?

Almost every plug-in space heater in the US tops out at 1,500 watts, because that is the most a standard 15-amp household circuit can safely supply for hours at a time. At full power it uses 1.5 kWh every hour.

Cost per hour = watts ÷ 1,000 × price per kWh
1,500 W at $0.17/kWh = 1.5 × 0.17 = $0.26 per hour

Run 8 hours a day for a month and that is about $61. The thermostat helps: once the room is warm, most heaters cycle on and off, so real use is often 50–75% of the maximum. The calculator lets you choose how much the heater runs.

Are some space heaters cheaper to run?

No. Ceramic, oil-filled radiator, infrared and fan heaters all turn 1 kWh of electricity into 3,412 BTU of heat. A 1,500 W model of any type costs the same per hour at full power. What differs is how the heat feels: infrared heats people and objects in front of it, oil-filled radiators give slow, even heat, and fan heaters warm a room fastest.

Space heater vs central heating

Heating one room with a space heater while turning the central thermostat down can save money if you spend most of the day in that room. Heating a whole house with space heaters almost never does, because a heat pump delivers two to three times as much heat per kWh. Compare fuels with the heating cost calculator.

Safety

Plug space heaters directly into a wall outlet, not an extension cord or power strip. Keep them three feet from curtains, bedding and furniture, and choose a model with tip-over and overheat shut-off.