How much does it cost to run a fan overnight in the UK?
A standard 50 watt pedestal fan left on for eight hours uses 0.4 kilowatt hours and costs 10.4p at the Ofgem cap rate of 26.11p per kWh, which is £3.13 over a month of hot nights. A low energy DC fan such as the MeacoFan on a quiet setting draws as little as 6 watts and costs 1.3p for the same eight hours.
What a fan actually draws
Fans sit in a wider band than most people expect, and the band has widened since direct current motors arrived.
A conventional mains motor pedestal fan is usually rated between 40 and 100 watts. Honeywell's HSF1630 comfort control stand fan is sold as a 45 watt unit, and Dyson rates the Cool AM07 tower fan at 56 watts. At the other end, DC models change the picture completely. Meaco rates the MeacoFan 1056P at 6 to 24 watts across its twelve speeds, which means the quiet setting most people use overnight costs almost nothing to run.
We use 50 watts as the everyday figure for a typical household fan, with 6 watts at the efficient end and 100 watts for a big floor fan on full.
Work it out for your own electric fan
Type in the wattage from the plate on the back, then your own unit rate. The numbers update as you type.
What a night costs
| Fan | Power | Per hour | Eight hour night | Month of hot nights |
|---|---|---|---|---|
| DC fan on a quiet setting | 6 W | 0.2p | 1.3p | 38p |
| DC fan on a higher speed | 24 W | 0.6p | 5.0p | £1.50 |
| Honeywell pedestal fan | 45 W | 1.2p | 9.4p | £2.82 |
| Typical mains fan | 50 W | 1.3p | 10.4p | £3.13 |
| Dyson tower fan | 56 W | 1.5p | 11.7p | £3.51 |
| Large floor fan on full | 100 W | 2.6p | 20.9p | £6.27 |
| Portable air conditioner | 1,100 W | 28.7p | £2.30 | £68.93 |
The last row is there for scale. Everything above it is cheap enough that the decision about whether to run a fan overnight should be made on sleep rather than on money.
| Appliance | Typical draw | Usage we assume | Per hour (UK) | Per usage (UK) | Per month (UK) | Per hour (US) |
|---|---|---|---|---|---|---|
| Electric fan | 50 W | per 8 hours overnight | 1.3p | 10.4p | £3.17 | 0.92 cents |
Rates: Ofgem cap 1 July to 30 September 2026 at 26.11p per kWh (source), EIA residential average June 2026 at 18.34 cents per kWh (source). Checked 2026-09-22.
The arithmetic, in one line
Divide the watts by a thousand, multiply by the hours, multiply by your unit rate.
A 50 watt fan is 0.05 kilowatts. Run it for eight hours and you have 0.4 kilowatt hours. Multiply by 26.11p and you get 10.4p. A British summer with 30 genuinely hot nights costs £3.13, and a hot spell of a full 60 nights costs £6.27.
Even the pessimistic version stays small. Run the same fan all day as well as all night, 24 hours for a fortnight, and you spend £4.39.
Where the real saving is
- Buy a DC fan next time rather than trying to run your existing one less. The gap between 50 watts and 12 watts is the whole cost of the appliance, and DC fans are also markedly quieter at the same airflow.
- Drop the speed by one setting. Fan power rises steeply with speed, so the second highest setting often moves nearly as much air for a third less power.
- Point the fan across the bed rather than at it. Air moving over your skin is what cools you, and a gentle crosswise breeze at a low speed beats a blast at full power.
- Use the timer. Most people are asleep within half an hour, and a two hour timer covers the part of the night that actually matters.
- Open the right window. A fan pushing air out of a window on the cooler side of the house at night moves far more heat than the same fan stirring a sealed room.
- Close curtains during the day. A room that never gets to 28 degrees does not need a fan at 2am, which is the only saving on this page worth more than a few pence.
Cooling fans and fan heaters are not the same appliance
A good share of the searches that land on this page are actually about fan heaters, so it is worth separating them properly. A cooling fan has a motor and nothing else, which is why it costs a penny an hour. A fan heater has a heating element behind the same fan, and at 2 kilowatts it costs 52.2p an hour, £4.18 for an eight hour night and £125 over a month of nights.
If you are choosing between the two on a bill, they are not in the same league. The fan is background noise on your statement and the fan heater is one of the most expensive things you can plug into a socket.
A fan cools people, not rooms
This is the part that changes how you use one. A fan does not lower the temperature of a room by a single degree, and the motor actually adds a small amount of heat to it. What a fan does is move air across your skin so that sweat evaporates faster, which makes you feel three or four degrees cooler than the thermometer says.
Two things follow from that. The first is that a fan running in an empty room is doing nothing at all, so the timer matters more than the speed. The second is that a small fan close to you beats a large fan across the room, because the effect depends on air moving over you rather than on the volume of air being shifted. A 12 watt desk fan a metre away will outperform a 100 watt floor fan in the corner, for an eighth of the cost.
What this costs in the United States
At the EIA residential average of 18.34 cents per kilowatt hour, an eight hour night with a 50 watt fan costs 7.3 cents, and a month of nightly use costs $2.20. Running that fan through a Texas summer, at under 16 cents a kilowatt hour and 90 nights, comes to $5.74. In California at nearly 35 cents the same 90 nights cost $12.51, which is still less than one evening of air conditioning.
Common questions
Do electric fans use a lot of electricity in the UK?
No, they are among the cheapest appliances in the house. Even a large oscillating pedestal fan at 100 watts costs 2.6p an hour, and the low energy DC models cost a fraction of a penny. A fan moves air rather than changing its temperature, which is why it is so cheap compared with anything that cools or heats.
How much does it cost per hour to run an electric fan?
Between 0.2p and 2.6p an hour depending on the motor and the speed. A 6 watt DC fan is 0.16p, a 45 watt Honeywell pedestal fan is 1.2p, a 56 watt Dyson tower fan is 1.5p, and a 100 watt industrial style floor fan is 2.6p.
How much does it cost to run a 2kW electric fan heater?
A great deal more, because a fan heater is a different appliance that happens to share a word. At 2 kilowatts it costs 52.2p an hour, which is 40 times the cost of a typical 50 watt cooling fan and £4.18 for an eight hour night.
Is it cheaper to run a fan or air conditioning overnight?
The fan, by a factor of more than twenty. A 1,100 watt portable air conditioner costs £2.30 for eight hours against 10.4p for a 50 watt fan. Air conditioning removes heat from the room, a fan only moves it past your skin, so the comparison is about comfort as much as cost.