🔥How much does it cost to run a space heater?
A space heater draws about 750 watts on low to 1,500 watts on high. Running 8 hours a day and the US-average 17¢/kWh, that’s about $31–$61 a month ($372–$745 a year) — roughly $0.13–$0.26 an hour while it’s on.
These are estimates, not a meter reading. The wattage and energy figures are typical US ranges and the 17¢/kWh is the national-average rate — the math is exact once you plug in your own wattage and rate. Your real cost depends on the specific unit, your settings and your utility.
Energy and cost, broken down
| Timeframe | Energy (kWh) | Cost @ 17¢/kWh |
|---|---|---|
| Per hour running | 0.75–1.5 | $0.13–$0.26 |
| Per day (8 h) | 6.0–12.0 | $1.02–$2.04 |
| Per month | 180–360 | $31–$61 |
| Per year | 2190–4380 | $372–$745 |
At the US-average 17¢/kWh. On a cheap rate (~11¢) these drop about a third; in California, New England or Hawaii (~33¢+) they roughly double. Ranges reflect the typical span of unit sizes and settings.
Why it costs what it does
Every electric space heater is essentially 100% efficient — all the watts become heat — so the wattage is the whole story and "energy-saving" heaters of the same wattage cost the same to run. Almost all plug-in heaters top out at 1,500 watts (the limit of a standard outlet), with a 750-watt low setting. What changes your bill is runtime: heating one occupied room with a 1,500-watt heater is cheap; leaving it on all day, or using several, adds up fast. Running one 1,500-watt heater 24/7 is about $183 a month.
How to run it for less
- Heat the person, not the house: use the heater in the one room you're in and turn the central thermostat down — that's where a space heater actually saves money.
- Use the thermostat and low (750 W) setting — once the room is warm, a heater cycling on low costs half of one running flat-out on high.
- Never run a space heater unattended or overnight for cost or safety — a timer or a model with a thermostat avoids heating an empty room.
- For a room you heat for hours every day, compare against your central heat: gas heat is usually cheaper per unit of warmth than any electric heater.
Keep going
Frequently asked
How much does it cost to run a 1500 watt heater for 24 hours?▾
About $6.10 a day at the US-average 17¢/kWh (1.5 kW × 24 h × $0.17), which is roughly $183 over a 30-day month. That's why a space heater is a cheap way to warm one occupied room for a few hours but an expensive way to heat a home around the clock. On the low 750-watt setting it's half that.
Do "energy-efficient" space heaters cost less to run?▾
No — two heaters of the same wattage produce the same heat and cost the same to run, because electric resistance heating is already ~100% efficient. Ceramic, infrared and oil-filled heaters differ in how they spread heat and how safe they feel, not in energy per watt. The only real savings come from a good thermostat and heating a smaller space, not from the heater's marketing.
How do I work out what a space heater costs to run for my electricity rate?▾
Take the wattage ÷ 1,000 to get kilowatts, multiply by the hours you run it, then by your electricity rate. Find your rate on your bill (total ÷ kWh used) — the US average is about 17¢/kWh, but it ranges from ~11¢ in the cheapest states to 30–42¢ in California, New England and Hawaii. So the same space heater costs roughly 35% less on a cheap rate and nearly double on an expensive one than the figures here.
What is the average price of electricity in the US?▾
About 17¢ per kWh for residential customers as a national average (2026). The cheapest states — parts of the Midwest and Pacific Northwest — sit near 11¢, while California, most of New England and Hawaii run 30¢ to over 40¢. Your exact rate is on your utility bill; divide the dollar total by the kWh used, or read the per-kWh charge directly.