Standby power: how much it really costs

KiloWise editorial team · Last updated 5 November 2026 · Category: Lighting & Appliances

Your television is off. The little red light beside the power button is on. Your games console is off too, but it is still warm to the touch. Is any of that costing you money? Yes — a small amount, all day, every day. This is standby power, and the question is not whether it exists, but whether it is worth doing anything about.

This guide gives you an honest answer. You will learn what standby power is, how much it typically costs, which devices are worth switching off at the socket and which are not, and how to measure your own home instead of guessing. There is a worked example at the end, priced in both US dollars and UK pounds, so you can see exactly what one device costs and scale it up to your own home.

What standby power actually is

Standby power — also called phantom load or vampire power — is the electricity a device uses while it is switched off but still plugged in. The device is not doing its main job, but part of it stays awake: waiting for a remote-control signal, keeping a clock running, staying connected to your Wi-Fi, or downloading an update in the background.

Almost every modern device draws some standby power. A television waits for the remote. A set-top box stays ready to record. A games console downloads updates overnight. A microwave keeps its clock lit. A printer waits for a print job. A phone charger plugged in with no phone attached draws a tiny amount. None of these is large on its own. The cost comes from the number of them, and from the fact that they draw power for 24 hours a day, 365 days a year.

Note the difference between genuine standby and a device that looks off but is actually working — a box recording a programme or a console downloading a game. The second is doing something you may want, so switching it off is not a saving.

How much does standby power cost?

Standby power accounts for roughly 5–10% of residential electricity use, and can cost up to about $183 a year in the US (EnergySage, Aug 2026). Treat both figures as context, not as your bill. The 5–10% is a share of electricity use across homes, and the $183 figure is an upper figure for a home with many always-on devices — not a typical or promised amount for your home.

To put the upper figure in context: the average US residential electricity bill was $144 a month in 2024 (US EIA, via NerdWallet). At that level, $183 a year works out at about $15.25 a month — a meaningful slice of a bill, but not the largest one. Heating and cooling are the biggest share of a typical home energy bill, at around half of it (ENERGY STAR), so standby is a second-tier saving: worth doing, not worth obsessing over.

Your own cost depends on three things: how many devices you have on standby, how much power each one draws, and what you pay per kilowatt-hour. A home with one television and a charger pays very little; a home with a television, a set-top box, two consoles, a printer and a soundbar, all on standby around the clock, pays noticeably more.

If you want to put a number on your whole home quickly, the standby power estimator does the arithmetic from the watts and hours you enter. This guide explains what the numbers mean and what to switch off first.

Which devices matter most — and which barely matter

The devices worth your attention are the ones that stay partly awake and draw power all day. The ones that barely matter are the ones that draw almost nothing, or that you only leave plugged in for short periods. The table below ranks the usual suspects. The ranking is about the kind of device, not a wattage claim — check the label on your own device, because two televisions of the same size can draw different amounts on standby.

Two devices deserve a special note. A set-top box or DVR can be one of the biggest standby draws in a home, but only switch it off when it is not recording and you do not need it to record overnight. A games console in instant-on mode is similar: it is convenient, but the convenience is the cost. Turning off instant-on in the console's settings usually cuts its standby draw sharply while keeping the console usable — it just takes a little longer to start.

How to measure standby power in your own home

Do not guess. Guessing is how a 1-watt charger becomes a £50-a-year monster in someone's head. There are two honest ways to measure, and both start with the label.

First, read the label on the device or its power supply. Many devices state their standby power in watts, sometimes printed as "standby power" in the manual or on the manufacturer's specification page. If the label gives a wattage, use that. If it gives only volts and amps, multiply them together to get watts — but be aware that the label usually states the maximum draw, not the standby draw, so a label figure can overstate standby power.

Second, use a plug-in electricity monitor — a small device that sits between the wall socket and the plug and shows the watts being drawn in real time. Plug the device in, switch it to standby, and read the watts. Leave it for a day if you can, and note whether the draw changes: some devices drop to almost nothing after a few minutes, while others stay awake. A monitor costs money, so borrow one if you can; a library, a neighbour, or a local energy advice service may lend one. You do not need to measure every device — measure the three or four biggest suspects and you will have most of the answer.

Once you have watts, the maths is simple. A kilowatt-hour is 1,000 watts used for one hour, so:

FORMULA: kWh per year = watts × hours per day × 365 ÷ 1,000

Multiply the result by your electricity rate to get the yearly cost. If you do not know your rate, find it on your bill — it is usually printed as a unit rate in cents or pence per kWh. Our guide to how to read your energy bill shows where to look. If you are in the UK and on a default tariff, the Ofgem price cap for Oct–Dec 2026 is 26.32p/kWh for electricity, but your supplier and region may differ, so check your bill first.

What is safe to switch off — and what is not

Most of what you switch off at the socket is perfectly safe. But some things should stay plugged in, and getting this wrong costs more than the electricity you save. Here is the line.

Safe to switch off at the socket: televisions, games consoles (once they have finished downloading and are not mid-update), printers, soundbars, microwaves, lamps, phone chargers, smart speakers, and desktop computer monitors. A switched-off socket or a power strip with a switch makes this a one-flick habit at night, rather than a crawl behind the television every evening.

Do not switch off: your fridge or freezer — ever. A fridge that warms up spoils food and, when it restarts, works harder to cool down again, which can wipe out any saving and cost you a fridge full of food. The same applies to any medical equipment that must stay powered, to security systems and alarms, and to any device that records on a schedule, such as a DVR that is set to record overnight. If a device is doing a job while you sleep — recording, updating, monitoring — let it do the job and switch it off when the job is done.

Two borderline cases deserve a deliberate decision. Your router: switching it off overnight saves a little, but it takes your Wi-Fi down, which matters if anyone relies on it overnight. The rule is simple — if switching it off stops something you rely on, leave it on; if it only stops a glowing light, switch it off.

One more caution: do not switch a device off mid-update. If a console, television or set-top box is installing an update, let it finish. Interrupting an update can corrupt the software and leave you with a device that needs a repair — a far bigger bill than the standby power ever was.

A habit that costs nothing

Standby power is one of the cheapest savings in the home because the fix is a habit, not a purchase. A power strip with a switch by the television, switched off at night, covers the television, the console, the soundbar and the set-top box in one movement. A strip by the desk covers the printer and the monitor.

Do not expect standby savings to transform your bill. Heating and cooling are around half of a typical home energy bill, so a thermostat change will move your bill far more than a standby habit will. Standby is one of the quick wins in a whole-home energy audit, and it pairs naturally with swapping your most-used bulbs for LEDs — see our guide to the LED lighting swap order. Small, certain and free is still worth doing; it is just not the whole plan.

Related: try the standby power estimator with your own devices, then read our guides to the LED lighting swap order and the whole-home energy audit for the next quick wins.

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