How much does an electric blanket cost to run in the UK?
An electric blanket costs about 2.7p an hour to run. On 27 October 2026 the Flexible Octopus electricity rate in London was 26.6p per kWh, from the Octopus Energy API, and a blanket draws around 100W, which is 0.1kWh an hour. Warm the bed for an hour every night for a whole winter and you are looking at under a fiver.
That makes it one of the cheapest ways to stay warm. Here is the sum, how it compares with heating a room, and the safety checks worth doing before you plug one in.
The sum
Cost per hour is watts, divided by 1,000, multiplied by your unit rate. For a 100W blanket at 26.6p:
0.1kWh × 26.6p = about 2.7p an hour.
The 100W figure is the typical one we use on Cheap Watts, and it assumes a higher setting to warm the bed. Your blanket's label will give its actual wattage, so check it.
Your rate will differ from London's, and so will your tariff. Your bill has your exact unit rate in pence per kWh.
| How you use it | Energy | Cost at 26.6p |
|---|---|---|
| One hour to warm the bed | 0.1kWh | about 2.7p |
| One hour a night, 26 winter weeks | about 18kWh | about £4.84 |
| One hour a night, all year | about 36kWh | about £9.68 |
| Eight hours at 100W, every winter night (not recommended, see below) | about 146kWh | about £38.72 |
The all-night figure is a worst case. It assumes the full 100W for the whole night, which most people don't need and most safety advice discourages.
How does it compare with heating a room?
The same appliance guide on the site assumes a 2kW electric heater running for two hours, five days a week. At 26.6p that is about £1.06 each time, and about £138 over 26 winter weeks.
Per hour, a 2kW heater uses 2kWh and a 100W blanket uses 0.1kWh. By my sum the blanket uses 5% of the energy. It works because it heats you and the bed, rather than the air and the walls of a room.
This is the same idea I covered in does turning your thermostat down by 1°C really save money. A blanket on the sofa changes how warm you feel more than the thermostat does, and an electric one makes that gap bigger. If you are still using a plug-in heater for hours at a time, an electric blanket is the first thing I would try instead.
It won't heat the house. It is for the bed, or for you under a throw. If you are cold in every room, the answer is different and probably involves insulation and draught-proofing. But for the cold-bed problem specifically, 2.7p is hard to beat.
How to get the best from it
- Warm the bed, then switch it off. Switch it on 30 to 60 minutes before bed and off when you get in. That keeps the bill at about 2.7p a night.
- Use the lowest setting you are comfortable with. Check your blanket's label for the wattage on each setting.
- Time it on a cheap-rate tariff. If you are on a time-of-use tariff, the cost per hour depends on the slot. The Cheap Watts price checker shows today's cheapest half-hours.
Is it safe? The checks to do first
Cheap is no use if it is not safe. Old and damaged blankets are a fire risk, so I would follow what Greater Manchester Fire and Rescue Service advises:
- Replace your electric blanket when it is more than 10 years old.
- Check it regularly for damage such as scorch marks, mould or exposed wires, and stop using it straight away if it is damaged.
- Unplug it before you get into bed, unless it has a thermostat control designed for safe all-night use.
- Never use a hot water bottle or have drinks while using it, because spills can cause electrical faults.
- Spread it out fully when in use, and store it flat or rolled. Folding or bunching can cause overheating.
- Buy from a reputable retailer, check it has the UKCA or CE mark, and don't buy second-hand.
If you are buying a new one, the all-night question is worth reading the instructions for. Only blankets designed for it should be left on, and only as the instructions say.
The short version
- An electric blanket costs about 2.7p an hour at 26.6p per kWh (London, Flexible Octopus, 27 October 2026).
- An hour a night through 26 winter weeks costs about £4.84.
- A 2kW heater uses 20 times the energy per hour, so for one person in bed the blanket is far cheaper.
- Replace it at 10 years old, check for damage, and unplug it before sleeping unless it is designed to stay on.
This week, find the label on your blanket, note the wattage, and work out your own cost per hour. If it is more than 10 years old, replace it before you use it this winter.