How Much Does a 1500-Watt Heater Cost to Run?
A 1500-watt space heater costs about $0.28 per hour at the national average rate of 18.44¢/kWh — or about $66/month running 8 hours a day.
Based on the US national average electricity rate of 18.44¢/kWh (EIA Electric Power Monthly, May 2026) and full rated wattage throughout. Formula: 1,500W ÷ 1,000 × hours × $/kWh. Use the calculator below to enter your exact rate.
Calculate Your 1500-Watt Heater Cost
1500-Watt Heater Cost by State
Based on 8 hours/day, 30 days/month — 360 kWh — at rated wattage throughout. State electricity rates: EIA Electric Power Monthly, May 2026. That is a single month, not a 2026 annual average.
| State | Rate (¢/kWh) | Per Hour | Per Day (8 hrs) | Per Month |
|---|---|---|---|---|
| National Average | 18.44¢/kWh | $0.28 | $2.21 | $66.38 |
| California | 33.25¢/kWh | $0.50 | $3.99 | $119.70 |
| Texas | 16.44¢/kWh | $0.25 | $1.97 | $59.18 |
| Florida | 15.17¢/kWh | $0.23 | $1.82 | $54.61 |
| New York | 29.93¢/kWh | $0.45 | $3.59 | $107.75 |
| Colorado | 16.16¢/kWh | $0.24 | $1.94 | $58.18 |
| Illinois | 23.85¢/kWh | $0.36 | $2.86 | $85.86 |
| Hawaii | 52.00¢/kWh | $0.78 | $6.24 | $187.20 |
Frequently Asked Questions
How much does it cost to run a 1500-watt heater for 24 hours?
Twenty-four hours at full power is 36 kWh. At the national average rate of 18.44¢/kWh that is about $6.64. At California's 33.25¢/kWh it is about $11.97, and in Hawaii at 52¢/kWh about $18.72.
Is a 1500-watt heater expensive to run?
Compared with central gas heating, yes — about three times more expensive per unit of heat. Electric resistance heat works out at roughly $54 per million BTU delivered at 18.44¢/kWh, against roughly $16 for a 92% AFUE gas furnace at $1.44/therm. For a single room that would otherwise mean heating the whole house, a space heater can still save money by letting you turn the central thermostat down.
Do all space heaters use 1500 watts?
Most standard-size plug-in space heaters are rated at 1500 watts on high and 750 watts on low. Some mini heaters run at 400W–900W, and some larger models go up to 2000W. Check the label on your unit.
How much does a 1500-watt heater cost per month?
Running 8 hours daily is 360 kWh, about $66/month at the national average rate. Running it continuously would be 1,080 kWh, or roughly $199/month nationally — and far more in high-rate states like California or Hawaii. Both figures assume full rated wattage; a thermostat holding a set temperature will bring them down.