How much electricity does a space heater use?
A space heater uses its wattage in watt-hours every hour it runs at full power. Nearly every plug-in heater sold in the US tops out at 1,500 watts, which a standard 120-volt, 15-amp household circuit can supply, and most have a lower setting: Lasko's popular 754200 runs at 900 watts on low. Electricity use and cost at the US average price, running 8 hours a day:
| Heater power | Per hour | Per 8-hour day | Per month | Per winter |
|---|---|---|---|---|
| 1,500 W1.50 kWh an hour | 27¢ | $2.16 | $65.66 | $325.98 |
| 1,000 W1.00 kWh an hour | 18¢ | $1.44 | $43.78 | $217.32 |
| 750 W0.75 kWh an hour | 13¢ | $1.08 | $32.83 | $162.99 |
| 400 W0.40 kWh an hour | 7¢ | 58¢ | $17.51 | $86.93 |
| 200 W0.20 kWh an hour | 4¢ | 29¢ | $8.76 | $43.46 |
At full power the whole time. A month is 365 ÷ 12 days; a winter is November through March (151 days). Cost at 17.99¢ per kWh, the EIA's US average residential price for the 12 months ending July 2026.
Most heaters don't run at full power all day. A heater with a thermostat switches its element off once the room reaches the set temperature and back on as it cools, so in a small, well-insulated room it may heat only part of each hour. A plug-in watt meter shows how much yours actually uses; enter the result in the calculator as a percentage of time heating.
Measure your heater's real power use
P3 Kill A Watt P4400
A plug-in meter that shows live watts and totals kWh and cost by day, week, month, or year.
How much does it cost to run a space heater?
It depends mostly on your electricity price, which varies more than threefold between states. A 1,500-watt heater running 8 hours a day at the average price for January to July 2026:
| State | Price per kWh | Per hour | Per month |
|---|---|---|---|
| North Dakota | 12.36¢ | 19¢ | $45.11 |
| Texas | 16.06¢ | 24¢ | $58.62 |
| Florida | 15.3¢ | 23¢ | $55.84 |
| Ohio | 18.7¢ | 28¢ | $68.25 |
| New York | 29.38¢ | 44¢ | $107.24 |
| California | 33.25¢ | 50¢ | $121.36 |
| Hawaii | 46.28¢ | 69¢ | $168.92 |
Your bill shows your own price per kWh, including delivery charges. Pick your state in the calculator or type your rate in.
Does a space heater use a lot of electricity?
Yes, compared with almost anything else you plug in. One 8-hour day on high uses 12 kWh, about as much as a typical refrigerator uses in 8 days. Electricity per 8 hours:
| Appliance | kWh | Cost |
|---|---|---|
| Space heater on high (1,500 W) | 12.0 kWh | $2.16 |
| Space heater on low (750 W) | 6.00 kWh | $1.08 |
| Personal heater (200 W) | 1.60 kWh | 29¢ |
| Queen heated blanket on high (about 100 W) | 0.80 kWh | 14¢ |
| Refrigerator, all day (about 65 W average) | 1.57 kWh | 28¢ |
Refrigerator: median of the ENERGY STAR certified 19–23 cu. ft. bottom-freezer models, for a full 24 hours; see our refrigerator power consumption page. Heated blanket figure from our heated blanket guide.
That's why warming yourself instead of the room is so much cheaper. A heated blanket or a small personal heater under your desk uses a fraction of the power of a full-size heater.
Are some space heaters more energy efficient?
Not really. Every electric space heater, whether ceramic, oil-filled, infrared or a fan heater, turns essentially all the electricity it uses into heat. A 1,500-watt heater of any type puts out about 5,118 BTU an hour. What differs is how the heat reaches you:
- Ceramic and fan heaters blow warm air and heat a small room quickly.
- Oil-filled radiators warm up slowly, then release heat quietly and keep radiating for a while after they switch off.
- Infrared heaters warm people and objects in front of them rather than the air, which feels warmer sooner if you sit close.
"Energy-saving" and "eco" modes save money by running at lower power or cycling off sooner, not by making heat more efficiently. A thermostat, a timer and a low setting are the features that actually cut your bill.
Low-wattage space heaters
If you want to warm one person rather than a whole room, a heater with a low setting or a small personal heater costs far less to run.
Best basic heater with a low setting
Lasko 754200 Ceramic Space Heater
A 9-inch ceramic heater with a 900 W low setting, 1,500 W high, an adjustable thermostat, and overheat protection.
The Lasko 754200 is one of the most-rated space heaters on Amazon, with nearly 35,000 ratings averaging 4.4 stars. Lasko lists it at900 watts on low and 1,500 on high, with an adjustable thermostat. On low, it costs about 16¢ an hour at the US average price.
Best quiet heater for bedrooms
De'Longhi ComfortTemp Oil-Filled Radiator (EW7707CM)
A silent oil-filled radiator with three power settings up to 1,500 W, an adjustable thermostat, and a ComfortTemp mode.
An oil-filled radiator has no fan, so it's silent, and it keeps giving off heat after its element cycles off. De'Longhi's EW7707CM has three power settings up to 1,500 watts, an adjustable thermostat, and a ComfortTemp mode that De'Longhi says is up to 20% more efficient than running the thermostat at its maximum. It has nearly 13,000 Amazon ratings averaging 4.4 stars.
Best personal heater
Lasko MyHeat Mini Personal Heater
A 6-inch, 400-watt ceramic heater for a desk or under it, with one heat setting and a cool-touch case.
At 400 watts, the MyHeat Mini uses about a quarter of a full-size heater's power, roughly 7¢ an hour. It's meant to warm your hands or feet at a desk, not a room. Lasko's original 200-watt MyHeat uses half as much again, but on Amazon it's mostly sold in packs of three.
Space heater safety
The US Consumer Product Safety Commission estimates that portable heaters were involved in an average of 1,700 fires a year, causing about 70 deaths and 160 injuries annually from 2017 to 2019. Its advice:
- Keep heaters at least three feet from anything that can burn, such as curtains, furniture and bedding.
- Plug an electric heater directly into a wall outlet, never an extension cord or power strip.
- Don't leave a heater running unattended in a small space around babies or anyone who can't move away from it.
A 1,500-watt heater draws 12.5 amps on high, most of a standard 15-amp circuit. Running a second heater, a microwave or a hair dryer on the same circuit can trip the breaker. Look for a heater with a tip-over switch and overheat protection, and turn it off when you leave the room or go to sleep.
How this calculator works
- Electricity = watts × hours × share of time heating ÷ 1,000. A month is 365 ÷ 12 days; a winter is November through March.
- Cost = kWh × your price per kWh. The default is the EIA's US average residential price for the 12 months ending July 2026; the state options are EIA averages for January to July 2026.
- Amps = watts ÷ 120 volts; BTU per hour= watts × 3.412.
Heating a garage or workshop? See our guide to the best garage heaters. Sizing an air conditioner instead? Try the BTU calculator.
Sources
All figures checked October 29, 2026.
- US Energy Information Administration, Electric Power Monthly, Table 5.3: average residential price, the 12 months ending July 2026 (17.99¢/kWh). www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_5_03
- EIA Electric Power Monthly, Table 5.6.B: average residential price by state, January to July 2026. www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_5_6_b
- US Consumer Product Safety Commission, "CPSC Warns Consumers to be Cautious When Using Space Heaters, Furnaces and Fireplaces This Winter" (2023). www.cpsc.gov/Newsroom/News-Releases/2023/CPSC-Warns-Consumers-to-be-Cautious-When-Using-Space-Heaters-Furnaces-and-Fireplaces-This-Winter
- Lasko 754200 specifications (900 W to 1,500 W). lasko.com/products/lasko-9-ceramic-space-heater-overheat-protection-2-heat-settings-thermostat
- Lasko MyHeat Mini (model 200) specifications (400 W). lasko.com/products/lasko-myheat-mini-6-personal-ceramic-space-heater-400w-1-heat-setting
- De'Longhi EW7707CM specifications (1,500 W, three power settings). www.delonghi.com/en-us/p/radiator-space-heater-comfort-temp-full-room-radiant-heater/EW7707CM-6A.html