Getting into a warm bed is a welcome comfort on a chilly night, but how much does an electric blanket cost to run? The answer depends on its wattage, how long you leave it on and what you pay for electricity.
We’ll show you how to estimate the cost for your blanket, with examples to help you see what an evening’s use could add to your bill. If you’re still choosing one, browse our best electric blankets or read our buying guide.
Find the three numbers you need
Look for the blanket’s rated power in watts (W), usually on its label, packaging or manual. Then note how long you normally leave it on and your electricity unit rate in pence per kilowatt-hour (kWh). Ofgem explains that the unit rate is the charge for each unit of energy used; your actual rate depends on your tariff.
A dual-control blanket may have more than one heated zone. Check whether its stated wattage is for the whole blanket or for one controller. Do not just double a single figure without checking the model instructions.
Use a simple calculation
Estimated cost in pence = (watts ÷ 1,000) × hours used × your unit rate in pence per kWh.
For example, a 120W blanket used for one hour at a hypothetical 30p per kWh: 120 ÷ 1,000 × 1 × 30 = 3.6p. Half an hour at the same rated power would be 1.8p.
The 30p rate is only a worked example, not a current tariff quote. Use the rate on your own bill. Electrical Safety First gives 80–120W as a typical electric-blanket range, with dual-controller types generally higher powered. The rating on your own blanket is the better number to use.
Why the actual bill may differ
The calculation assumes the blanket draws its full rated power for the whole period. A thermostat may cycle the heat on and off, and lower settings can change consumption. You can get a closer figure with a suitable plug-in electricity monitor, used according to its instructions, or by comparing your meter readings over a controlled period. Do not infer an exact running cost from a retailer’s “pennies per night” claim.
The daily standing charge is separate from the unit rate. If you already have an electricity supply, it is not an extra charge caused by switching on the blanket. And a blanket only reduces your overall heating bill if it actually lets you use less energy elsewhere; keeping the room heating unchanged adds the blanket’s cost on top.
Compare common patterns of use
Using the same hypothetical 120W blanket and 30p unit rate, half an hour of pre-heating costs up to 1.8p at full rated power. Thirty such evenings would come to about 54p. Leaving it on for eight hours would give a full-power estimate of 28.8p for that night—but do not choose overnight use from the maths alone. Follow the exact manufacturer instructions and safety guidance.
Keep the use safe
Electrical Safety First recommends switching an electric blanket off before sleep or choosing one with automatic shut-off if it is to stay on overnight. Check for wear, keep it flat rather than folded in use, and do not combine it with a hot-water bottle. A lower electricity cost is never a reason to ignore the product instructions.
Frequently asked questions
How do I work out the cost of my own electric blanket?
Find the rated watts on the blanket or in its manual. Divide by 1,000, multiply by the hours it is on, then multiply by your electricity unit rate per kWh. Treat that as an estimate, not a meter reading.
Does a dual-control blanket cost twice as much?
Not necessarily. Its total power rating, which sides are on, the heat settings and the time used all matter. Use the exact model’s rating or measure its actual electricity use.
Does the standing charge belong in the per-use calculation?
Usually not when you are comparing the extra cost of using a blanket in a home that already has electricity. The daily standing charge is billed regardless of whether the blanket is switched on.
Does a timer reduce the cost?
It can reduce electricity use if it switches the blanket off sooner than you otherwise would. The saving depends on the blanket’s power and the time it would have stayed on.
