A modern home hums with devices that never switch off: the broadband router, the smart speaker, the doorbell, the various little boxes with a standby light. None of them draws much at any one moment, but running every hour of every day, the constant loads add up to a real, if modest, slice of the electricity bill. Knowing which are worth leaving on, and which are quietly wasteful, keeps that slice in proportion.
What the router costs
A broadband router draws only a handful of watts, but because it typically runs around the clock those watts accumulate into a steady annual figure, the kind of small constant load that the running cost calculator shows is more than the moment-to-moment draw suggests. It is not a large cost, comfortably in the every-little-helps category rather than among the heavy hitters, but it is real, and it is the archetype of the always-on device: trivial per hour, noticeable per year.
Why people leave it on, and when that is right
Routers are usually left on permanently for good reasons. They take a few minutes to reconnect, some home services such as internet-connected security cameras, smart heating or a landline that runs over broadband depend on the connection staying up, and frequent power cycling does the hardware no favours. For a household that uses the connection through the day, or relies on always-connected devices, leaving the router on is the sensible choice and the small running cost is the price of the convenience. There is little point switching it off for the sake of pennies if it disrupts things you rely on.
When switching off is worth it
The case for turning it off is narrow but real. If the house is genuinely empty and nothing depends on the connection, for instance overnight in a home with no smart devices or while away on holiday, switching the router off saves its standing draw and is fine for the hardware over those longer breaks. The judgement is simply whether anything needs it while you are not there. For most connected homes the answer is yes for short absences and no for long ones, so the holiday switch-off is the main opportunity.
The other always-on bits
Beyond the router sit the smart speakers, the voice assistants, the video doorbell, the standby lights on chargers and appliances, and the clocks on the oven and microwave. Individually each is tiny; collectively they form the baseline load your house draws even when you are doing nothing. The honest position, set out more fully in the standby power guide, is that this baseline is worth a tidy-up but not an obsession. Find the genuinely thirsty always-on devices with a plug-in monitor and deal with those; leave the truly trivial ones be.
Keeping it in proportion
The always-on loads are a useful reminder of the principle running through this whole site: chase the big users first. The router and its companions are worth knowing about and tidying where it costs you nothing, but they will never rival the heating, the hot water or the tumble dryer. Switch off the entertainment cluster at night, turn the router off when the house is empty for a stretch if nothing needs it, and then stop worrying about the small constant loads and put your effort where the real money goes.