Space heater cost per hour and month
A resistance heater converts electricity directly into heat. The wattage and full-power runtime therefore determine energy use. The examples below assume four full-power hours per day and use the latest national residential average only as a benchmark.
At 1,500 watts, four full-power hours per day equals 6 kWh per day and 180 kWh in a 30-day month.
Thermostat cycling changes actual consumption
If the heating element runs only half the time, effective runtime is about half the clock time. A plug-in energy meter can measure this cycling and provide a more accurate monthly input.
Use space heating strategically
A space heater may reduce whole-home heating needs when it heats one occupied room and the central thermostat is reduced. Running several heaters for long periods can instead create a major winter load.
Frequently asked questions
How much does a 1,500-watt space heater cost per hour?
At the 2026-05 U.S. residential average of 18.44 cents per kWh, one full-power hour costs about $0.28. Use your own electricity price for a local estimate.
How many kWh does a space heater use?
A 1,500-watt heater uses 1.5 kWh per full-power hour. Four full-power hours use 6 kWh. Thermostat cycling may reduce actual element runtime.
Can a space heater lower an electric bill?
It may help when one occupied room is heated while the central thermostat is reduced, but several heaters or long runtimes can cost more. Compare the same heating need and actual runtime.
U.S. Energy Information Administration, Electricity Retail Sales, residential average price. Latest monthly data: 2026-05; comparison baseline: 2025 annual. Verified 2026-08-05. Monthly prices can vary seasonally and are not utility-specific rates.