Quick summary: Your router costs under 3p a night to run: £19 to £32 a year for a BT Smart Hub 2. What switching it off overnight saves, and why BT advises against it.

How Much Electricity Does a Wi-Fi Router Use? And Should You Turn It Off at Night?

The short answerCap rates current 1 July to 30 September 2026

A typical UK broadband hub draws roughly 7 to 16 watts. By BT's own power document, a Smart Hub 2 uses 8.48 to 14.10 watts, which works out at about £19 to £32 a year at the current price cap average of 26.11p per kWh, our arithmetic, shown below. That is under 3p a night. Turning it off overnight saves around £6 to £11 a year, and your provider would rather you did not: BT warns regular switch-offs "can make the line appear unstable", Plusnet warns the DLM system may "reduce your speed", and on a broadband-based landline an off router is a dead phone.

Somewhere between the smart meter display and the cost of everything, the router under the telly has come under suspicion. Here is the full audit: official manufacturer wattages, real running costs at the live price cap, the honest size of the overnight saving, and the provider-sourced reasons to leave it on anyway. And because this site exists to save you money properly: the same energy instinct, pointed at your broadband tariff instead of its plug, is worth roughly ten times more.

The short version

Official figures exist and almost nobody quotes them. BT: 14.10 W in operation, 8.48 W in network standby for the Smart Hub 2. EE: 11.1 W for its Wi-Fi 7 hub. Sky, Virgin Media and Vodafone publish none we could find, and we looked in their own ESG reports and spec pages.
Running cost is £16 to £48 a year across the major hubs at 26.11p per kWh, most sitting in the £20s. Under 3p a night.
Overnight switch-off saves £6 to £11 a year on a typical hub, our arithmetic, before its costs.
The costs are real: possible speed cuts on copper lines (BT's and Plusnet's words, not ours), missed updates, and no landline while the router is off.
The ten-times bigger saving is the tariff. Ofcom: out-of-contract customers pay £7 to £9 a month more. That is £84 to £108 a year, against £6 to £11 for the plug.

How much electricity does a router use?

Direct answer: roughly 7 to 16 watts for the hubs UK providers supply, on a mix of official documents and independent testing.

Two providers publish proper power documents. BT's official consumption sheet for the Smart Hub 2 lists 14.10 W in operation, 8.48 W in network standby and 0.04 W off, with the hub dropping to standby after 20 minutes. EE publishes equivalents: 11.1 W in operation for the Wi-Fi 7 Smart Hub 7 Plus, 20.83 W for the Smart Hub Pro, and a 23 W maximum rating for the Smart Hub Plus, a maximum being a differently defined, higher figure than typical draw.

Sky, Virgin Media and Vodafone publish no official consumer wattage that we could find, and the search was not casual: we opened Sky Group's environment pages and its governance document list, Virgin Media O2's Sustainability Performance Update 2024 and its hub specification pages, and Vodafone's own device guide, whose Power Hub specification page lists ports, Wi-Fi bands and security but no power entry at all, confirmed on two separate reads. For those three, the best available figures are independent: ISPreview's 2024 testing round-up, which measured or compiled 10 W typical for Sky's Broadband Hub, 13.49 to 15.51 W for Virgin Media's Hub 5, 8.5 to 14.33 W for Vodafone's Ultra Hub and 7.29 to 10.6 W for TalkTalk's Wi-Fi Hub 2. Usefully, ISPreview's BT figures match BT's official document exactly, which is a good sign for the rest of its table. Zen, the one ISP that answers this question for its customers directly, puts the general range at "between 5 and 20 watts of power".

What that costs per year, at the live price cap

Direct answer: between about £16 and £48 a year across the major hubs, with most in the £20s. Here is the working.

Ofgem's price cap for 1 July to 30 September 2026 puts the average electricity unit rate for a Direct Debit customer at 26.11p per kWh. The formula is watts x 24 hours x 365 days, divided by 1,000 for kWh, multiplied by the unit rate. Every cost below is our own arithmetic from those inputs, always-on for a full year, so treat them as ceilings for each wattage.

Annual running cost at 26.11p per kWh (Ofgem cap average, 1 July to 30 September 2026). Costs are our own calculation; wattages are graded by source.
Hub	Wattage and source	kWh per year	Cost per year
BT Smart Hub 2	8.48 W standby to 14.10 W operation (BT official document)	74.3 to 123.5	£19.40 to £32.25
EE Smart Hub 7 Plus	11.1 W operation (EE official document)	97.2	£25.39
EE Smart Hub Pro	20.83 W operation (EE official document)	182.5	£47.64
Sky Broadband Hub (SR203)	10 W typical (reported: ISPreview testing, 2024)	87.6	£22.87
Virgin Media Hub 5	13.49 W idle to 15.51 W load (reported: ISPreview, 2024)	118.2 to 135.9	£30.85 to £35.47
Vodafone Ultra Hub	8.5 W idle to 14.33 W load (reported: ISPreview, 2024)	74.5 to 125.5	£19.44 to £32.78
TalkTalk Wi-Fi Hub 2	7.29 W idle to 10.6 W load (reported: ISPreview, 2024)	63.9 to 92.9	£16.67 to £24.24

Per day, the whole table sits between roughly 4.6p and 13p. Per night, the dearest hub here costs under 5p and the typical one under 3p. Hold that scale in mind for the next section. One date for your diary: Ofgem publishes the October to December cap by 26 August 2026, so these costs will shift slightly within weeks of publication; forecasts already circulate, but the wattages will not change and neither will the formula, so we will simply re-run the sums the day Ofgem confirms.

Always-on for a year: what each hub costs

Upper-end figures from the table above, at 26.11p per kWh. Our own arithmetic.

EE Smart Hub Pro

£47.64

Virgin Media Hub 5

£35.47

BT Smart Hub 2

£32.25

EE Smart Hub 7 Plus

£25.39

Sky Broadband Hub

£22.87

TalkTalk Wi-Fi Hub 2

£24.24

BT and EE figures are calculated from official manufacturer power documents; Sky, Virgin Media and TalkTalk from testing reported by ISPreview in March 2024. Real bills land lower where hubs idle in standby for much of the day.

Should you turn your router off at night?

Direct answer: you can, it will save £6 to £11 a year, and your providers would rather you did not, for three reasons they state themselves.

First the saving, honestly calculated. Eight hours off per night, every night, spares a Smart Hub 2 running at 14.10 W about 41.2 kWh a year, which is £10.75 at the current cap; at its 8.48 W standby draw the same routine saves £6.47. Call it £6 to £11 for a typical hub, under 3p a night. Now the other side of the ledger, in the providers' own words.

What switching off saves

Around £6.47 to £10.75 a year for a BT Smart Hub 2 switched off eight hours a night, our arithmetic at 26.11p per kWh.
Slightly more for hungrier hubs, slightly less for efficient ones.

What it risks, per the providers

Speed cuts on copper lines. BT: "Switching the hub off regularly can make the line appear unstable. This may cause your speed to be reduced to keep the connection reliable." Plusnet: turning it off frequently "can cause DLM to think there's a problem and reduce your speed".
Missed updates. Zen: routers receive "important firmware updates, usually overnight".
A dead landline. If your phone runs over broadband, no powered router means no calls, including emergency calls, all night.

The speed mechanism deserves one plain paragraph, because it sounds like an urban myth and is not. Copper-based lines (FTTC and ADSL) are watched by an automatic stability system called Dynamic Line Management. Plusnet's help pages define it and draw the conclusion in two sentences: "DLM is an automated system that manages the performance of your broadband service", and "DLM is the main reason that we advise you to leave your router switched on, as turning it off frequently can cause DLM to think there's a problem and reduce your speed." TalkTalk describes the same system watching new lines: monitoring "for around 10 days using our Dynamic Line Management system", during which it asks you to "keep your router switched on at all times". EE says the same about its first ten days of line tests. And BT's business help spells out the consequence beyond the settling-in period: "If you switch off your hub or router, it can appear as though your broadband is disconnected from our network. This might make the line look like it can't cope with high speed, so the line speed might be automatically reduced to make the line more stable." A nightly off-switch looks, to that system, like a nightly fault. Full fibre lines do not retrain this way, but the updates point and the landline point still apply to every technology; our guides to broadband that slows at night and digital phones in a power cut cover the neighbouring territory.

The landline point is the one growing teeth. Millions of home phones now run over broadband ahead of the analogue switch-off on 31 January 2027, and Ofcom's guidance is blunt that broadband-based calls "will not function" without powered equipment. An overnight-off router turns a digital landline into an ornament until morning, which matters most in exactly the households most likely to be economising.

Our verdict, plainly: leave it on, treat the £6 to £11 as the price of a stable line, a patched router and a working phone, and if the energy instinct is itching, point it at the next section, where the same effort pays ten times more. If your hub is old enough to be inefficient, it may also simply be old: how long a router lasts covers when to ask for a replacement, and whether you can keep your router when you switch answers the follow-up.

The £84 to £108 hiding on the same bill

Direct answer: if you want a bill-cutting habit this month, the router is the wrong appliance. The broadband tariff itself is the one with the money in it.

Two figures put the plug-switching economy in its place. The Energy Saving Trust puts the entire avoid-standby habit, every gadget in the house, at "around £45 a year in GB and £55 in NI", a figure its page attaches to no particular price cap. Meanwhile Ofcom's February 2026 research found that "customers who are in contract spend between £7 and £9 a month less than out-of-contract customers": £84 to £108 a year, on our arithmetic, from a single phone call or switch, with 28% of broadband customers currently on the wrong side of it.

So the genuinely energy-efficient move is thirty seconds at the comparison, not 365 trips to the plug socket. Check what your postcode offers, then read our guides to deals for existing customers and saving money on broadband for the rest of the routine.

Find the saving that is bigger than the plug

Free and independent. Thirty seconds, ranked by total contract cost.

Adrian's take

I admire the instinct behind this question enormously, and I want to redirect it. The reader who asks what the router costs to run is the reader who checks things, and checking things is the whole game. But the router is a decoy: three pence a night, wearing warning labels from two providers. The £9 a month is in the tariff, the £45 a year is in the telly corner's standby pile, and the router is the one gadget in the house that earns its keep around the clock, patching itself in the small hours and keeping the phone alive. Switch your deal, switch the telly off properly, and let the little fellow hum.

Frequently asked questions

How much electricity does a Wi-Fi router use in the UK?

Roughly 7 to 16 watts for the hubs most UK providers supply. BT's official power document for the Smart Hub 2 states 14.10 watts in operation and 8.48 watts in network standby. EE's documents state 11.1 watts in operation for the Smart Hub 7 Plus and 20.83 watts for the Smart Hub Pro. Industry testing reported by ISPreview in 2024 measured Sky's Broadband Hub at around 10 watts and Virgin Media's Hub 5 at 13.49 to 15.51 watts.

Which providers publish official router power figures?

BT and EE do, in power consumption documents linked from their own sites, which is where this page's 14.10, 8.48, 11.1 and 20.83 watt figures come from. Sky, Virgin Media and Vodafone publish none that we could find: we opened Sky Group's environment pages and governance document list, Virgin Media O2's 2024 sustainability update and hub spec pages, and Vodafone's own device guide, whose specification page for its hub lists ports, Wi-Fi and security but no power entry. For those three, the only figures available are independent measurements.

How much does it cost to run a router 24 hours a day?

At the July to September 2026 price cap average of 26.11p per kWh, a 10 watt hub running constantly costs about £22.87 a year and a 14.10 watt hub about £32.25, our own arithmetic using watts multiplied by 24 hours and 365 days. Per night it is under 3p. The exact figure depends on your hub, your tariff and how often the hub idles in standby.

Should I turn my Wi-Fi router off at night?

Providers advise against it. BT's help pages say to keep the hub switched on at all times, warning that switching it off regularly can make the line appear unstable and may cause your speed to be reduced. Plusnet is even plainer: turning it off frequently can cause DLM to think there is a problem and reduce your speed. Routers also receive updates at quiet times, and if your landline runs over broadband a powered-off router cannot make or receive calls. The saving is around £6 to £11 a year for a typical hub.

Does turning off the router at night save money?

A little. Eight hours off per night saves a 14.10 watt hub about 41 kWh a year, roughly £10.75 at the current cap, and a hub idling at 8.48 watts about £6.47, our own arithmetic. Set against that, BT and Plusnet warn repeated switch-offs can trigger speed reductions on some lines, and Ofcom's research shows out-of-contract broadband customers pay £7 to £9 a month over the odds, which dwarfs any overnight saving.

Will turning my router off damage my broadband speed?

It can on copper-based lines. BT's business help explains that if you switch off your hub, it can appear as though your broadband is disconnected, which might make the line look like it cannot cope with high speed, so the line speed might be automatically reduced to make the line more stable. Plusnet's help pages name the mechanism, Dynamic Line Management, and give the same warning. Full fibre lines do not retrain in the same way, though updates and digital voice still argue for leaving any router on.

What is Dynamic Line Management (DLM)?

In Plusnet's definition, DLM is an automated system that manages the performance of your broadband service, and it is the main reason providers advise leaving the router switched on: turning it off frequently can cause DLM to think there is a problem and reduce your speed. TalkTalk describes monitoring and tweaking your speed for around 10 days using its Dynamic Line Management system when a line first goes live. It applies to copper-based lines, trading speed for stability.

Do routers update overnight?

Broadly yes. Zen states that routers receive important firmware updates, usually overnight, enhancing their security and performance. Sky says it updates hub software automatically with nothing for the customer to do. A router that is unplugged every night has fewer quiet windows in which to take those updates.

Does a router use much power in standby?

Standby here means network standby, idling while connected, and it is most of a router's life. BT's figures for the Smart Hub 2 are 8.48 watts in network standby against 14.10 in operation, with the hub entering standby after 20 minutes. Fully off is different: 0.04 watts. The gap between 8.48 and 14.10 watts is why annual costs are best given as a range.

How much does a BT Hub cost to run per year?

Between about £19.40 and £32.25 a year at the July to September 2026 cap of 26.11p per kWh, our own arithmetic from BT's official figures of 8.48 watts in network standby and 14.10 watts in operation for the Smart Hub 2. That is between 5.3p and 8.8p a day.

Is my landline affected if I turn the router off at night?

If your phone runs over broadband, yes: no powered router, no calls, in or out, including emergency calls. Ofcom's guidance notes that calls made over broadband will not function without power because the equipment at the premises needs mains power. With millions of landlines moving onto broadband before the analogue switch-off on 31 January 2027, this is becoming the strongest reason to leave the router on overnight.

Should I unplug my router when I go on holiday?

For a long absence the saving is real and the nightly objections matter less, though on copper-based lines the connection can take time to settle back to full speed afterwards, and any broadband-based phone, alarm or smart device at home stops working while it is off. Weigh what in the house depends on the connection before pulling the plug.

Do newer Wi-Fi 7 routers use less electricity?

EE's own published figures point that way at the mid-range: its Wi-Fi 7 Smart Hub 7 Plus lists 11.1 watts in operation against 20.83 watts for the Smart Hub Pro, though its Smart Hub Plus lists a 23 watt maximum, a differently defined figure. Efficiency varies by model rather than generation alone, so check the power information document for the specific hub.

References

BT. (n.d.). BT Smart Hub 2: Power consumption info. https://www.bt.com/content/dam/bt/help/sh2-user-guides/bt-smart-hub-2-power-consumption.pdf
BT. (n.d.). What affects Wi-Fi signal in your home? https://www.bt.com/help/broadband/fix-a-problem/broadband-and-wi-fi/five-steps-to-improve-slow-bt-broadband-speeds
BT Business. (n.d.). Fixing slow broadband and Wi-Fi speeds. https://business.bt.com/help/article/broadband-and-internet/broadband-speed/fixing-slow-broadband-and-wi-fi-speeds/
EE. (n.d.). EE Smart Hub Plus (SH31B and SH32B): Power information. https://ee.co.uk/content/dam/help/terms-and-conditions/general/declaration-of-conformity/f5394-smart-hub-plus-sh31b-sh32b-power-information.pdf
EE. (n.d.). EE Smart Hub 7 Plus (SH35A): Power information. https://ee.co.uk/content/dam/help/terms-and-conditions/general/declaration-of-conformity/ERV46BE247B-H2-SA%20Smart%20Hub%207%20Plus%20SH35A%20Power%20Information.pdf
EE. (n.d.). Smart Hub Pro user guide, v9. https://ee.co.uk/content/dam/help/user-guides/ee-smart-hub-pro-userguide-v9.pdf
EE. (n.d.). About broadband speed. https://ee.co.uk/help/broadband/fix-problem/about-broadband-speed
Energy Saving Trust. (2026, May 20, last updated). Quick tips to save energy. https://energysavingtrust.org.uk/hub/quick-tips-to-save-energy/
Jackson, M. (2024, March 30). The 2024 electricity costs of big UK ISP home broadband routers. ISPreview UK. https://www.ispreview.co.uk/index.php/2024/03/the-2024-electricity-costs-of-big-uk-isp-home-broadband-routers.html
Ofcom. (2018, October 10). Protecting access to emergency organisations when there is a power cut at the customer's premises. https://www.ofcom.org.uk/phones-and-broadband/telecoms-infrastructure/access-emergency-organisations-power-cut
Ofcom. (2026, February 26). New Ofcom research reveals how to cut phone and internet bills. https://www.ofcom.org.uk/phones-and-broadband/bills-and-charges/new-ofcom-research-reveals-how-to-cut-phone-and-internet-bills
Ofgem. (2026, May 27). Changes to energy price cap between 1 July and 30 September 2026. https://www.ofgem.gov.uk/news/changes-energy-price-cap-between-1-july-and-30-september-2026
Plusnet. (n.d.). Broadband terminology guide. https://www.plus.net/help/archive/broadband/broadband-terminology-guide/
Sky. (n.d.). Sky hub and booster software. https://www.sky.com/help/articles/automatic-software-updates-for-sky-routers
TalkTalk. (2026, May 19, last modified). Your first 10 days of broadband. https://help-centre.talktalk.co.uk/Setting_up_my_service/New_order/Your_first_10_days_of_broadband
Zen Internet. (2024, February 26). How much power does my WiFi router use, and when should I switch it off? https://www.zen.co.uk/blog/posts/zen-blog/2024/02/26/how-much-power-does-my-wifi-router-use-and-when-should-i-switch-it-off/

Written by Adrian James, Broadband Editor at BroadbandSwitch.uk (LinkedIn). Reviewed by Dr Alex J. Martin-Smith (LinkedIn). Published 9 August 2026, wattages and cap rates last verified 8 August 2026 and the cap rate re-confirmed unchanged on 9 August 2026. Energy costs use the 1 July to 30 September 2026 cap average for Direct Debit customers; your tariff and region will vary. This guide is information, not advice.