Space Heater electricity cost calculator
In this example, a space heater at 1500W and 100% duty cycle costs $0.272 per scheduled hour. At 8.00 hours per day, that is $66.33 per 30.44 use days, using the August 2026 US average of 18.16¢/kWh. Adjust the calculator for your appliance and electricity bill.
Space Heater electricity cost calculator
Use watts and running time, or enter energy from a label, meter or completed load. Your inputs stay on this device.
Enter a number within each field’s limits to calculate your cost.
Your estimated energy cost
4,380 kWh across 365 use days per year
Power mode includes your selected duty cycle. The monthly figure assumes 30.44 use days; the annual total uses your selected use days. These are estimates at the entered rate.
Energy charges only. Fixed utility fees, purchase, installation and maintenance are excluded. See the calculation method and sources.
Running cost at different usage times
These examples hold 1500W, 100% duty cycle and 18.16¢/kWh constant. They illustrate the arithmetic, not recommended schedules. Follow the manufacturer’s operating instructions.
| Hours per use day | kWh per day | Cost per day | 30.44 use days |
|---|---|---|---|
| 0.5 | 0.750 kWh | $0.14 | $4.15 |
| 1 | 1.500 kWh | $0.27 | $8.29 |
| 4 | 6.000 kWh | $1.09 | $33.17 |
| 8 | 12.000 kWh | $2.18 | $66.33 |
How to estimate your space heater electricity use
For a resistance space heater, the setting and the time spent actively heating drive electricity use. A 1,500W setting draws 1.5 kW while the heating element is on; a thermostat can reduce the share of time it stays on.
The 24-hour example represents 24 hours drawing the entered power. It is not a recommendation to leave a portable heater running unattended; follow its manufacturer instructions.
- Use the wattage for your selected setting. At the same actual draw and runtime, oil-filled, ceramic and other resistance heaters use the same electrical energy.
- At an illustrative $0.20/kWh, 1,500W at continuous full power costs $0.30 for one hour or $2.40 for eight hours. A 50% duty cycle halves those energy figures over the same selected hours.
- For a 90-day season at eight full-power hours/day, the same example costs $216. The 365-day equivalent is $876 and should not be mistaken for a winter forecast.
- Comparing a room heater with central heating requires the rooms heated, runtime, central-system efficiency and fuel prices. Wattage alone cannot establish which option costs less.
Calculation and data sources
Daily kWh = watts ÷ 1,000 × hours × duty cycle ÷ 100. Multiply kWh by your rate in dollars per kWh to get cost. The wattage, hours and duty cycle above are editable example assumptions, not EIA measurements of this appliance.
The US and state average prices come from the EIA for August 2026. A state average is a starting point; your bill is the better source for your tariff.
Electricity running cost by state
Sorted by average electricity price. These reference figures use 8.00 hours per day at 100% duty cycle, for 30.44 days per month and 365 days per year. Seasonal use will cost less than this year-round scenario. Click a state to load its rate.
| State | Rate /kWh | Per month | Per year | Relative |
|---|---|---|---|---|
| Nevada | 12.72¢ | $46.46 | $557 | |
| Louisiana | 12.87¢ | $47.01 | $564 | |
| Utah | 13.31¢ | $48.62 | $583 | |
| North Dakota | 13.31¢ | $48.62 | $583 | |
| Idaho | 13.37¢ | $48.84 | $586 | |
| Tennessee | 13.42¢ | $49.02 | $588 | |
| Nebraska | 13.54¢ | $49.46 | $593 | |
| Kentucky | 13.80¢ | $50.41 | $604 | |
| Arkansas | 14.37¢ | $52.49 | $629 | |
| Wyoming | 14.43¢ | $52.71 | $632 | |
| Mississippi | 14.43¢ | $52.71 | $632 | |
| Washington | 14.63¢ | $53.44 | $641 | |
| Oklahoma | 14.82¢ | $54.13 | $649 | |
| North Carolina | 14.95¢ | $54.61 | $655 | |
| Florida | 14.99¢ | $54.76 | $657 | |
| Arizona | 15.05¢ | $54.97 | $659 | |
| South Dakota | 15.15¢ | $55.34 | $664 | |
| Kansas | 15.47¢ | $56.51 | $678 | |
| Montana | 15.57¢ | $56.87 | $682 | |
| South Carolina | 15.76¢ | $57.57 | $690 | |
| Georgia | 15.90¢ | $58.08 | $696 | |
| Texas | 15.91¢ | $58.12 | $697 | |
| Oregon | 15.92¢ | $58.15 | $697 | |
| Missouri | 16.02¢ | $58.52 | $702 | |
| West Virginia | 16.31¢ | $59.58 | $714 | |
| Alabama | 16.33¢ | $59.65 | $715 | |
| New Mexico | 16.51¢ | $60.31 | $723 | |
| Indiana | 17.02¢ | $62.17 | $745 | |
| Iowa | 17.06¢ | $62.32 | $747 | |
| Colorado | 17.17¢ | $62.72 | $752 | |
| Minnesota | 17.20¢ | $62.83 | $753 | |
| Virginia | 17.64¢ | $64.44 | $773 | |
| Delaware | 18.70¢ | $68.31 | $819 | |
| Illinois | 19.32¢ | $70.57 | $846 | |
| Ohio | 19.38¢ | $70.79 | $849 | |
| Wisconsin | 19.41¢ | $70.90 | $850 | |
| Maryland | 21.40¢ | $78.17 | $937 | |
| Pennsylvania | 21.77¢ | $79.52 | $954 | |
| Michigan | 22.99¢ | $83.98 | $1,007 | |
| Vermont | 23.84¢ | $87.08 | $1,044 | |
| Connecticut | 24.51¢ | $89.53 | $1,074 | |
| New Jersey | 24.61¢ | $89.90 | $1,078 | |
| District of Columbia | 25.98¢ | $94.90 | $1,138 | |
| New Hampshire | 27.64¢ | $101 | $1,211 | |
| Rhode Island | 28.18¢ | $103 | $1,234 | |
| New York | 28.65¢ | $105 | $1,255 | |
| Alaska | 29.41¢ | $107 | $1,288 | |
| California | 29.75¢ | $109 | $1,303 | |
| Massachusetts | 30.48¢ | $111 | $1,335 | |
| Maine | 32.11¢ | $117 | $1,406 | |
| Hawaii | 47.18¢ | $172 | $2,066 |
Common questions
How much electricity does a space heater use?
In this example, 1500 watts at a 100% duty cycle uses 1.500 kWh per scheduled hour. At 8.00 hours per day, that is 12.000 kWh per use day. Your model and operating conditions can differ.
How much does it cost to run a space heater for an hour?
The default example costs $0.272 per scheduled hour at the US average of 18.16¢/kWh for August 2026. This includes the selected duty cycle. Enter your watts, duty cycle and electricity price for your own estimate.
Does the annual cost assume I use it every day?
The reference tables use 365 days at the stated daily hours; monthly figures use 30.44 days. These are comparison scenarios, not forecasts. For a heater used on 90 days, enter 90 use days per year in the calculator.
Why does electricity running cost vary by state?
For August 2026, the EIA state averages range from 12.72¢/kWh in Nevada to 47.18¢/kWh in Hawaii. Equal electricity use costs more at a higher rate. Your utility tariff can differ from the state average.
How much does a 1,500 watt heater cost for eight hours?
At full power it uses 1.5 kW x 8 hours = 12 kWh. Multiply 12 by your price in dollars per kWh; at an illustrative $0.20/kWh, the cost is $2.40. Thermostat cycling can reduce actual energy use.
What does running a space heater for 24 hours cost?
At a continuous 1,500W, 24 hours uses 36 kWh. At an illustrative $0.20/kWh that is $7.20. A lower setting or cycling changes the calculation; this is an energy estimate, not advice about safe operating duration.
Does a lower-wattage heater always save money?
It costs less per hour while drawing less power, but may need to run longer to provide the same heat. Compare energy used over a comparable heating task, not just the wattage printed on the box.