Space heater running cost calculator

Electric resistance heaters use about 1 kWh for each hour they draw 1,000 watts. The important inputs are the heat setting, how long the element actually runs, and your electricity unit price.

Start with your actual usage

• Check the selected heat setting. A heater with a 2,000W maximum may also have a lower setting.
• If the thermostat switches the element off, adjust the active-time percentage below.
• Compare costs for the same room and comfort level; a lower wattage alone does not establish lower total heating cost.

A worked example

The following uses an illustrative rate of 0.25 currency units per kWh. It is not a current country tariff or a measured average for this appliance.

What this estimate leaves out

Assumes continuous heating at your entered power. Thermostat cycling can reduce actual use. Fixed charges are excluded. Time-of-use rates and tiered pricing need separate calculations. Annual results assume the same daily use for all 365 days, which can overstate seasonal appliance use.

How to calculate it yourself

If you already know the energy used, multiply measured kWh directly by your unit price. See the full methodology.