How much does it cost to run a laptop per hour in the UK?

Entertainment By Ellen HartwellPublished 28 October 2026

What a laptop actually draws

The number printed on the charger is the most a laptop can take from the socket, which makes it the wrong number to cost your day with. Apple ships the 13 inch MacBook Air with a 30 or 35 watt adapter, Lenovo gives its IdeaPad Slim 5 a 65 watt one, and the Legion 5 gaming laptop comes with a 245 watt brick. Each machine spends most of its working life well below those ceilings.

The low end is lower than most people guess. Apple's environmental report for the M4 MacBook Air measures it at 3.63 watts sitting idle with the screen on and Wi-Fi connected, tested on 230 volt mains. The battery tells the same story from a different angle, because 53.8 watt hours lasting up to 15 hours of web browsing works out at an average of about 3.6 watts. Lenovo's figures for the IdeaPad Slim 5 give 60 watt hours over 17.4 hours of video, which is about 3.4 watts. Even the Legion 5, a gaming machine, gets through the MobileMark office benchmark at roughly 14 watts.

Real homes draw more than a lab does, and that is the number we use. Researchers at Lawrence Berkeley National Laboratory in California metered laptops at the socket in ordinary households and found an average of 32 watts whenever they were on, a figure that includes the hours spent recharging the battery. A UK household survey they cite found 32.3 watts. We take 32 watts as the everyday figure, which is cautious for a new ultrabook and closer to the mark for an older machine that is charging while you work.

Per hour, per day and per month

The month column assumes eight hours a day, five days a week. The bottom two rows only apply while a game is running, so a gaming laptop used for spreadsheets in the day and games in the evening sits somewhere between the second row and the last.

Rates: Ofgem cap 1 October to 31 December 2026 at 26.32p per kWh (source), EIA residential average June 2026 at 18.34 cents per kWh (source). Checked 2026-09-22.

Charging it, and leaving it plugged in

Filling a battery from empty costs less than people expect, because laptop batteries are small. The MacBook Air holds 53.8 watt hours, and Apple measures its adapter at 88.8 per cent efficient on UK mains, so a full charge pulls about 0.06 kilowatt hours from the wall and costs 1.6p. A gaming laptop with an 80 watt hour battery costs about 2.4p to fill, and charging the MacBook from flat every day for a year comes to £5.82.

Leaving the charger in the wall with nothing attached costs even less. Apple measures its empty adapter at 0.08 watts, which is 18.4p over a whole year, and a phone charger behaves the same way, as our guide to leaving a phone charger plugged in shows with its own measured figures. What does cost money is a laptop left awake. At 32 watts around the clock it uses 280 kilowatt hours a year and costs £73.78, while the same laptop asleep at Apple's measured 0.29 watts would cost 67p.

A laptop against a desktop for working from home

This is the comparison most people searching the question are really weighing. The same Berkeley study measured desktop computers at 66.1 watts on average, before the monitor, and a 24 inch office monitor such as the Dell P2425H adds 10.6 watts according to its ENERGY STAR certification. That makes 77 watts at the desk against 32 watts on the laptop.

Over an eight hour day the laptop costs 6.7p and the desktop setup costs 16.2p. Across a year of working weekdays the gap is £24.64. That is real money, though it rarely decides the question alone, because a laptop that drives an external monitor picks up that 10.6 watts too, and the heating in the room you work in costs far more than either machine.

Gaming laptops are a different appliance

A gaming laptop on a desk at home behaves much more like a small gaming PC than like the machine described above. The Legion 5 with a GeForce RTX 5060 allows its graphics chip 115 watts, and once the processor, screen and fans are added a demanding game can push the whole machine towards its 245 watt charger. An hour of that costs between 3.0p and 6.4p, and three hours a night for a month lands between £2.72 and £5.80.

That still comes in under a desktop gaming rig, which we cost at 400 watts in our guide to what a gaming PC uses per month. The laptop wins on running cost because its parts are built to run from a battery, even when they are plugged in.

What actually lowers the cost

• Let it sleep. The step from 32 watts awake to 0.29 watts asleep is worth far more than anything else on this list, and Apple's own default sends the MacBook Air to sleep after ten minutes of inactivity.
• Shut the lid at the end of the day rather than leaving the screen on a lock page, since an idle machine with its display lit still draws several watts.
• Count the extras. A 24 inch external monitor adds 0.28p an hour, which is a third of the laptop itself, so switch it off at the monitor when you finish.
• Stop worrying about the charger in the wall. At 18.4p a year it is one of the cheapest things plugged in anywhere in the house.
• Cap the frame rate or pick a quieter performance mode when you game, because on a gaming laptop those settings decide whether an hour lands nearer the 115 watt figure or the 245 watt one.

What this costs in the United States

At the EIA residential average of 18.34 cents per kilowatt hour, a 32 watt laptop costs 4.7 cents for an eight hour day and about $1.02 for a month of working weekdays. Left awake around the clock for a year it costs $51.41, which is the one habit worth changing on either side of the Atlantic.