The clocks haven't even gone back yet and the first cold mornings have already sent people hunting for a way to stay warm without watching the meter spin. That search got a lot more pointed on 1 October, when the Ofgem price cap rose by around 4% for the October to December quarter. Gas went up by roughly 8%, while electricity rose by much less.
So here's the practical question: is an electric blanket really that much cheaper than turning the heating up? Mostly yes, but the answer depends on which blanket you own and how you use it.
What does an electric blanket cost to run?
Electricity is billed in kilowatt hours (kWh). One kWh is a 1,000-watt appliance running for an hour. To work out your own cost, use this:
Watts ÷ 1,000 × hours used × your unit rate (in pence) = cost in pence
Uswitch recently worked through some examples using the July price cap electricity rate of 26.11p per kWh:
- A 40W blanket costs about 8p for a night, or roughly £30.50 over a year.
- A 250W blanket costs about 52p a night.
- A 24kW gas boiler running flat out costs around £1.76 an hour, using a gas rate of 7.33p per kWh.
A quick caveat: those figures use the July rates. Your rate from 1 October will be slightly different, and it depends on your tariff and region, so check your own bill. The formula above lets you do the sum with your real number in about ten seconds.
Check the wattage too. It's printed on the label or in the manual. Most blankets use somewhere between 100 and 300 watts when heating, according to Uswitch's experts, and many cycle on and off once they reach temperature, so the real cost is often lower than the label suggests.
Why a blanket beats heating the whole house
Central heating warms every room, whether or not anyone is in it. A blanket only warms the small space around you. That's the whole trick, and it's why the comparison is so lopsided. Heating a whole home flat out for an hour can cost more than running a typical blanket for several nights.
That said, it isn't a like-for-like swap. A blanket won't dry your washing, stop damp patches forming or keep a cold hallway from feeling miserable. If you have a baby, an elderly relative or anyone with a health condition in the house, don't cut the heating below a level that's safe for them just to save money.
Underblanket, overblanket or heated throw?
Underblankets
These go beneath your sheet and warm the mattress. They're built for pre-heating a bed and, if they have the right safety features, for leaving on low.
Overblankets
These sit on top of you like a duvet layer. They feel nicer for sitting up in bed but tend to use more power.
Heated throws
The sofa option. They're handy if you're working from home and want to warm yourself rather than the room. The cost per hour is similar to a blanket, but the hours add up faster if you sit under one all day. A 100W throw used for six hours a day is 0.6kWh, which is about 16p a day at the July rate. Still modest, but it's not "pennies" if you do it every day for months.
How to use it without wasting money (or taking risks)
Uswitch suggests turning the blanket to full heat for 10 to 15 minutes before bed and then switching it off, or using a low setting for up to two hours before you get in. Pre-heating is the point of a blanket, so there's usually no need to keep it running all night.
Safety matters here as much as cost. Electrical Safety First, the UK charity, recommends:
- Checking regularly for scorch or burn marks and for visible or damaged wires.
- Replacing your blanket every ten years, or sooner if the fabric is worn, the wiring is showing or the controller buzzes or smells.
- Never using a blanket that is folded, rucked or creased, and never holding it in place with pins.
- Storing it loosely folded in a cool, dry place.
- Only leaving it on overnight if it has temperature controls plus safety features like automatic shut-off and overheat protection. Otherwise, unplug it when you get into bed.
- Looking for UKCA or CE marks, but not relying on them alone, because some sellers use the marks fraudulently. Buy from a reputable retailer rather than an unknown third-party seller, and avoid second-hand blankets.
Many local fire services also run blanket-testing events in autumn. If yours does, it's worth taking an older blanket along.
What to look for when buying
You don't need to spend much. Check these first:
- Wattage. Lower wattage means lower running costs, but check it's enough to warm you comfortably.
- Auto shut-off. A timer or automatic switch-off is the single most useful safety and cost feature.
- Overheat protection. Essential if you plan to leave it on while you sleep.
- Washable. Check whether it's machine washable, and whether the controller detaches.
- Size. Match it to your bed so you aren't paying to warm bits of mattress nobody's lying on.
Prices change often and discounts are common as winter approaches, so it's worth comparing before you buy. Our October sales guide covers what's worth buying now versus waiting for, and our energy price cap guide explains what the October rise means for your household. You can also browse Home & Garden deals or see all stores for current voucher codes on heating and bedding retailers.
Other cheap ways to stay warm
A blanket works best as part of a cheap-warmth routine rather than a replacement for everything:
- Layer up first. A thermal base layer and warm socks cost nothing to run.
- Close curtains at dusk. It helps hold heat in, and it's free.
- Draught-proof the obvious gaps. Doors and letterboxes are common culprits and the fixes are cheap.
- Use a hot water bottle. Boil only as much water as you need.
- Heat the room you're in. Lower the thermostat slightly overall and warm the space you're actually using.
- Check your tariff. If your fixed deal is ending, compare before you roll onto a standard variable rate.
FAQs
How much does it cost to run an electric blanket for a night?
Using Uswitch's July-rate figures, around 8p for a 40W blanket and around 52p for a 250W one. Use the formula above with your own unit rate for a better estimate.
Is an electric blanket cheaper than central heating?
Per hour it usually is, because it warms you rather than the whole house. It can't replace heating where damp, vulnerable people or cold rooms are a concern.
Can I leave an electric blanket on all night?
Only if it's designed for it: temperature controls, automatic shut-off and overheat protection. Otherwise, unplug it when you get into bed, as Electrical Safety First advises.
How often should I replace an electric blanket?
Every ten years is the recommendation, or sooner if you see damage or scorching.
What watt blanket should I buy?
Lower-wattage models cost less to run. Pick the lowest wattage that keeps you comfortable, and check the safety features before the price.
Does the price cap rise affect blanket running costs?
Slightly. The cap rose about 4% overall on 1 October, with gas going up by more than electricity, so blankets are still comparatively good value. The exact difference depends on your tariff.
Sources: Uswitch figures via Press News Agency (5 October 2026); Electrical Safety First. Running costs use July 2026 price cap rates as quoted by Uswitch.