A space heater is one of the most-searched “how much does it cost to run” questions every winter, and the answer is refreshingly simple because a resistance heater turns almost all its power into heat.
Estimate. Figures use the US average residential rate of 18.56¢/kWh (EIA, March 2026). Your rate and usage will differ — check your bill.
The quick answer
A standard 1,500-watt space heater uses 1.5 kWh per hour. At the US average rate:
| Hours per day | kWh/day | Cost/day | Cost/month |
|---|---|---|---|
| 4 hours | 6 kWh | ~$1.11 | ~$33 |
| 8 hours | 12 kWh | ~$2.23 | ~$67 |
| 12 hours | 18 kWh | ~$3.34 | ~$100 |
| 24 hours | 36 kWh | ~$6.68 | ~$200 |
Running it on the low (750 W) setting roughly halves every figure.
It depends a lot on your state
The same 1,500 W heater at 8 hours a day costs very different amounts depending on where you live:
| State | Rate (¢/kWh) | Cost/month (8 h/day) |
|---|---|---|
| Washington | 14.40¢ | ~$52 |
| US average | 18.56¢ | ~$67 |
| New York | 28.55¢ | ~$103 |
| California | 33.35¢ | ~$120 |
See the full list on the electricity prices by state pages, or price your exact setup in the running-cost calculator.
How to cut the cost
- Heat the room, not the house — turn down the central thermostat and warm only where you are.
- Use the low setting and a timer — 750 W is plenty for a small room.
- Never run two 1,500 W heaters on one circuit — it’s a fire risk, not a saving.
Bottom line
At 8 hours a day, a 1,500 W space heater costs roughly $67 a month at the US average rate — modest for one room, but expensive if you try to heat a whole home with several of them. For the appliance page with low/typical/heavy tables, see space heater running cost, and compare it with a central air conditioner and heat pump.