How much does a space heater cost to run?

The formula

cost = watts × hours ÷ 1,000 × price per kWh

Worked example: 1,500 W × 8 h ÷ 1,000 = 12 kWh a day. 12 kWh × $0.1831 = $2.20 a day, or about $65.92 over 30 days.

How many watts does a space heater use?

Most are rated 900 to 1,500 W. The exact figure is on the label on the back or bottom.

• Most U.S. plug-in space heaters top out at 1,500 W on high, because a standard 120 V / 15 A household circuit can only safely carry about that much. CPSC staff testing found even a heater advertised as 2,000 W measured a maximum input of 1,500 W.
• Typical two-setting ceramic heaters are 900 W on low and 1,500 W on high (e.g. Lasko 754200: 900 W / 1,500 W, 5,118 BTU/h on high).
• Ceramic, oil-filled, infrared and fan-forced heaters all turn electricity into heat at essentially the same efficiency (DOE lists electric resistance heating at 95–100% efficient). A heater marketed as "energy efficient" with the same wattage costs the same per hour. What changes your bill is wattage × hours.
• With a built-in thermostat, the heater cycles off once the room reaches the set temperature, so real-world hours on full power are often lower than the hours it's plugged in. A plug-in energy meter tells you the actual kWh.

Cost at different electricity prices

Per month (30 days) and per year (12 such months). Real use is usually seasonal. Average residential prices for July 2026 from the same EIA table. Your utility's rate, including delivery charges, may differ. Check the price per kWh on your bill.

Ways to pay less

1. Turn the central thermostat down when you use it A space heater only saves money if it lets you heat one room instead of the whole house. Running it on top of your normal central heat just adds its full cost to the bill. DOE estimates you can save as much as 10% a year on heating by setting your thermostat back 7–10°F for 8 hours a day.
2. Use low and the thermostat, not high all day Low (≈900 W) costs about 40% less per hour than high (1,500 W). Heat the room on high, then drop to low or let the thermostat cycle it off.
3. Use a timer instead of running it all night Running 1,500 W around the clock is about 1,080 kWh a month, roughly $198 at the U.S. average rate. CPSC also advises never leaving a heater running unattended or while you sleep. Many models have a built-in auto-off timer.
4. Close the door and stop drafts A space heater is a zone heater. Closing the door and blocking drafts keeps the heat you've paid for in the room, so the thermostat cycles off sooner.
5. If you rely on electric heat every winter, price a heat pump DOE says heat pumps can provide up to three times more heat than the electricity they use and can cut electricity use for heating by about 50% compared with electric resistance heat like baseboards and space heaters.

Safety. Plug space heaters directly into a wall outlet, never an extension cord or power strip, and keep them at least 3 feet from beds, curtains, and furniture (CPSC).