When the temperature drops, most people reach for one of two things: a space heater or a heated blanket. Both keep you warm, but the difference in running cost is much bigger than most people expect. In this guide we do the math with current electricity prices, so you can see exactly what each one costs per hour, per night and per month.
The Short Answer
A heated blanket is roughly 7 to 15 times cheaper to run than a typical space heater. A heated throw uses about 100 watts, while most plug-in space heaters use 1,500 watts on their high setting. At an average U.S. electricity price of about 18 cents per kWh, that is around 2 cents an hour for a heated throw versus about 27 cents an hour for a space heater on high.
How to Calculate the Running Cost of Any Heater
You can work out the cost of running any electric appliance with one simple formula:
Watts ÷ 1,000 × hours used × price per kWh = cost
You will find the wattage on the product label or listing, and your price per kWh on your electricity bill. For the examples below we use 18.2 cents per kWh, the 2026 average U.S. residential price forecast by the U.S. Energy Information Administration. Your own rate may be higher or lower depending on your state and utility.
Cost Comparison Table
These figures assume the device runs at full power the whole time. In real life, heaters with a thermostat and blankets with lower heat settings cycle on and off, so actual costs are usually lower.
| Device | Power | Per Hour | 8 Hours (One Night) | 30 Nights |
|---|---|---|---|---|
| Space heater (high) | 1,500 W | $0.27 | $2.18 | $65.52 |
| Space heater (low) | 900 W | $0.16 | $1.31 | $39.31 |
| Oil-filled radiator (high) | 1,500 W | $0.27 | $2.18 | $65.52 |
| Mini desk heater | 500 W | $0.09 | $0.73 | $21.84 |
| Queen heated blanket (dual control, both sides on) | about 220 W | $0.04 | $0.32 | $9.61 |
| Heated throw | about 100 W | $0.02 | $0.15 | $4.37 |
Why Heated Blankets Cost So Much Less
A space heater warms the air in a whole room. Much of that heat escapes through windows, walls and doors, so the heater has to keep running to replace it. A heated blanket puts a small amount of heat directly against your body and the blanket traps it there. You are heating one person, not a room full of air.
When a Space Heater Makes More Sense
- You need to warm a room for several people, such as a living room or home office with guests.
- You are moving around, cooking or working at a desk where a blanket is not practical.
- The room is very cold and you want the air itself to feel comfortable, not just your body.
- You need to take the chill off a bathroom before a shower (use a heater approved for bathrooms).
When a Heated Blanket Makes More Sense
- You are sitting still on the couch watching TV or reading.
- You want to warm up your bed before you get in.
- You live alone or only one or two people need to be warm.
- You want to keep your thermostat lower and cut your heating bill.
The Cheapest Way to Stay Warm: Use Both Smartly
Many households get the best results by combining the two. Lower the central thermostat by a few degrees, use a space heater only in the room you are actually using and only for as long as you need it, and switch to a heated blanket once you sit down or get into bed. Running a 1,500 W heater for one hour instead of four, and a heated throw for the rest of the evening, can save several dollars a day in the coldest months.
More Ways to Cut Winter Heating Costs
- Use the thermostat or ECO mode on your space heater instead of leaving it on high.
- Close doors to rooms you are heating so the warm air stays in.
- Block drafts under doors and around windows.
- Use a timer so heaters and blankets switch off automatically.
- Choose the smallest device that does the job: a 500 W desk heater for your feet, a throw for the couch, a queen blanket only when you need the whole bed warm.
Safety Reminder
Whichever you choose, plug space heaters directly into a wall outlet, keep them at least 3 feet from anything that can burn, and turn them off when you leave the room or go to sleep. For heated blankets, keep them flat, never fold them while switched on, and replace old or damaged ones. Read our full guide on how to use a heated blanket safely.
Frequently Asked Questions
How much does it cost to run a space heater all night?
A 1,500 W space heater running on high for 8 hours uses 12 kWh. At 18.2 cents per kWh, that is about $2.18 a night, or around $65 a month if you do it every night. Using a thermostat or a low setting can reduce this.
How much does it cost to run a heated blanket?
A 100 W heated throw costs about 2 cents per hour to run, or roughly 15 cents for 8 hours. Even a queen blanket with both sides on usually costs well under 50 cents a night.
Is a heated blanket cheaper than central heating?
For warming one person, yes. Central heating warms the whole house, which takes far more energy. Turning your thermostat down a few degrees and using a heated blanket in the evening is one of the simplest ways to lower a winter energy bill.
Bottom Line
If you just need to keep yourself warm while sitting or sleeping, a heated blanket wins on cost by a wide margin. If you need to warm a room, a space heater is the right tool, but use it only where and when you need it. If you are shopping for either, see our guides to the best space heaters and the best heated blankets.