How much does it cost to run a under-desk space heater?
A typical under-desk space heater draws about 500 watts. Used 8 hours a day, that works out to roughly $0.68 per day, $10.20 per month, and $122.40 per year on an average electricity rate of 17¢ per kWh. Compact under-desk heaters consume moderate power but may lead to lower overall heating costs through zone heating.
Under-Desk Space Heater running cost calculator
- Per day
- $0.68
- Per month
- $10.20
- Per year
- $122.40
- CO₂ / year
- 288 kg
Based on 720 kWh per year. Adjust the price per kWh to match your latest electricity bill for an exact figure.
The number that matters most is your own electricity rate. Rates range from under 11¢ per kWh in some regions to over 30¢ in others, so the same under-desk space heater can cost two or three times as much depending on where you live. Enter your exact rate in the calculator above to get a figure tailored to your bill.
Heating appliances like the under-desk space heater are usually seasonal, so your real annual cost depends heavily on your climate and how many months you run it. The figures here assume average year-round use — if you only switch it on during the coldest part of the year, scale the monthly cost by the number of months you actually use it.
At 500 watts, the under-desk space heater is a moderate load: not the largest item on your bill, but enough that long daily use is noticeable over a year. It is a good candidate for an efficiency upgrade if your current unit is old.
Over a full year this under-desk space heater uses about 720 kWh of electricity and is responsible for roughly 288 kg of CO₂ emissions on an average grid. Since it is used only part of the year, your real footprint scales with the season — the annual figure assumes a typical usage pattern.
To put the draw in everyday terms, one hour of running this under-desk space heater uses about as much electricity as charging a smartphone 42 times. It is a rough comparison, but it makes an abstract wattage figure easier to picture.
If this under-desk space heater is one you use daily, even small efficiency gains compound. Cutting its usage or wattage by 20% would save around $24.48 every year — money that an efficient replacement can recover over its lifetime.
Frequently asked questions
- How much does it cost to run a under-desk space heater per hour?
- At 500 watts and a 17¢/kWh rate, a under-desk space heater costs about $0.09 per hour to run.
- How much electricity does a under-desk space heater use per month?
- Running 8 hours a day, a under-desk space heater uses roughly 60.0 kWh per month, costing about $10.20.
- How many kWh does a under-desk space heater use per year?
- Used 8 hours a day for 180 days a year, a under-desk space heater consumes about 720 kWh annually — that is the figure your electricity rate is multiplied by to get the $122.40 yearly cost.
- Is a under-desk space heater expensive to run?
- Not particularly — at around $122.40 per year, a under-desk space heater is a relatively minor part of most electricity bills.
- How much CO₂ does a under-desk space heater produce?
- On an average grid, a under-desk space heater used this much is responsible for roughly 288 kg of CO₂ per year. The exact figure depends on how clean your local electricity supply is.
- How can I reduce my under-desk space heater running costs?
- Use it during off-peak hours if your utility offers time-of-use pricing, reduce daily run time, and consider an ENERGY STAR rated under-desk space heater, which uses less power for the same job.