Running a 1,500-watt space heater 8 hours a day in Washington costs about $52.64 a month — $0.22 an hour on full power at Washington's average 14.42¢/kWh.
At 14.42¢/kWh — Washington average, Jan–Aug 2026 (EIA). That is 21% below the U.S. average of 18.19¢.
| Period | kWh | Cost |
|---|---|---|
| Per hour of use | 1.5 | $0.22 |
| Per day | 12 | $1.73 |
| Per month | 365 | $52.64 |
| Per season (9 mo) | 3,285 | $474 |
Normal mean temperature (NOAA, population-weighted). Highlighted months average below 60°F.
| Heat source | $ per million Btu | This much heat |
|---|---|---|
| Heat pump (ENERGY STAR avg) | $17.09 | $21.28 |
| Gas furnace, 95% AFUE | $17.91 | $22.30 |
| Gas furnace, 80% AFUE | $21.26 | $26.48 |
| Space heater / baseboard | $42.26 | $52.64 |
In Washington resistance heat costs 2.4× as much as gas heat from a 95% furnace. A space heater only saves money when it lets you turn the whole-house thermostat down several degrees and heat just the room you're in. A heat pump delivers the same heat for about $21.28 a month.
| Heater | Per hour | 8 h/day, month | 24 h/day, month | Season (9 mo, 8 h) |
|---|---|---|---|---|
| 750 W | $0.11 | $26.32 | $78.96 | $237 |
| 900 W | $0.13 | $31.58 | $94.75 | $284 |
| 1,500 W | $0.22 | $52.64 | $157.92 | $474 |
1.5 kW × 8 h = 12 kWh a day; × 30.42 days = 365 kWh a month; × 14.42¢ (Washington average, Jan–Aug 2026, EIA) = $52.64.
Because resistance heat costs 2.4× as much as gas heat in Washington, a space heater saves money only if it lets you turn the whole-house thermostat down and heat just the room you're in. If your home heats with electric baseboards or furnace strips, a space heater costs the same per Btu — the saving comes only from heating fewer rooms.
The average Washington home used 954 kWh a month in 2025 (EIA); this heater adds 38% to that while it runs.
The full method, material data and tips are on the main space heater cost calculator page.