Updated June 29, 2026

Space Heater Cost Per Hour Calculator

Calculate the hourly, daily, and monthly cost of running a space heater using its wattage and your electricity price.

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Calculate your actual running cost

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Find watts on the appliance label. Your bill shows the price per kWh.

Estimated monthly cost$54.60182.0 kWh per month
Per hour$0.45
Per day$1.80
Per year$655.20

Running this space heater for 4 hours a day, 7 days a week uses about 182.0 kWh each month.

Quick answer

How much does a space heater cost to run?

A 1,500 W space heater used for 4 hours a day, 7 days a week, consumes about 182.0 kWh per month. At $0.30 per kWh, that is approximately $54.60 per month. Replace these example figures with the wattage and electricity rate from your appliance and bill.

What changes the real running cost?

Most plug-in space heaters use resistance heat, so their cost per hour is closely tied to the wattage setting selected on the heater.

If the thermostat cycles the heater on and off, reduce the hours to estimate active heating time rather than time plugged in.

Assumptions used in this example

This page starts with 1,500 watts, 4 hours of use per day, and 7 days per week. Those defaults are only a practical starting point. Replace them with the number on your product label, energy label, smart plug, or electricity bill.

Formulawatts / 1,000 x hours x price per kWhMonthly estimates use weekly kWh x 52 / 12.

Example space heater costs

These examples use 1,500 W for 4 hours a day and 7 days per week.

Electricity ratePer hourPer monthPer year
$0.15 / kWh$0.22$27.30$327.60
$0.25 / kWh$0.38$45.50$546.00
$0.35 / kWh$0.52$63.70$764.40

Ways to reduce the cost

Start with changes that reduce active runtime without compromising safety or the job the appliance needs to do.

  • Use the lowest comfortable heat setting.
  • Close doors to the room being heated.
  • Never use damaged cords or cover a heater while running.

Estimate only. Actual consumption varies by model, setting, condition, temperature, duty cycle, and tariff. Use a plug-in meter or energy-label figure when accuracy matters.

FAQ

Space heater running cost questions

How do I calculate space heater running cost?

Divide the watts by 1,000 to get kilowatts, multiply by the hours used, then multiply by your electricity price per kWh. This page pre-fills 1,500 W, 4 hours per day, and 7 days per week as a starting example.

How much does a space heater cost per hour?

At 1,500 W and $0.30 per kWh, the example cost is about $0.45 per hour while it is actively using that power. Change the rate field to match your own bill.

Why might my real space heater cost be different?

If the thermostat cycles the heater on and off, reduce the hours to estimate active heating time rather than time plugged in.

Should I use rated watts or measured watts?

Rated watts are useful for a quick estimate, but measured wall power or an energy-label kWh figure is usually more accurate because many appliances cycle on and off or change power during use.

Does the calculator include standing charges, taxes, or demand charges?

No. The calculator estimates usage cost from kWh only. If your bill includes standing charges, taxes, delivery fees, or demand charges, add those separately.

Can I share my result?

Yes. Use the share or copy button after entering your wattage, hours, days, rate, and currency. The page stores those inputs in the URL so you can revisit the same estimate.