What does a router / modem (24/7) cost to run?

The router or modem is the definition of an always-on appliance. It draws only around 10-15W, but it runs 24 hours a day, every day, because no one turns the internet off. That continuous duty means its small wattage still translates into a steady, year-round trickle on the bill, modest but utterly reliable.

The reason it never switches off is simple: the whole point of home internet is to be there whenever you reach for it. Smart TVs check in overnight, phones sync in the background, and any security cameras or smart-home gear you own need the connection alive around the clock. So the router quietly runs its 10-15W through every hour of the year.

There is essentially nothing to do about it, and that is fine. You cannot sensibly switch your internet off overnight, and the draw is too small to justify the hassle even if you could. Powering it down each night might save a dollar or two across a whole year while breaking every overnight update and download, which is a poor trade.

The router is here as the baseline of household standby load, the floor of what your home draws when everything else is off. When you flick every switch and unplug every appliance, this steady little draw is roughly what is left, the irreducible hum of a connected house.

That makes it a useful yardstick rather than a target. Its handful of watts is the price of admission for being online at all, and it is genuinely not worth chasing. The appliances worth chasing are the ones drawing this kind of constant power without needing to, the ones that could switch off and simply do not.

See standby and phantom load for the real hunt. The router earns its keep every hour of the day, but the TV cluster, the chargers and the boxes idling in instant-on standby often draw as much or more for no good reason. Add the router to the calculator to see the size of your always-on floor, then go after the loads that do not have to be there.