What does a wi-fi router and modem cost to run?

Router plus modem, running continuously. At the US average rate of 18.34¢ per kilowatt-hour that is $19 a year.

Electronics and computing · Rated 12 W · 100% duty cycle

Running cost, US average rate

$19a year

105 kWh a year · $1.61 a month · 12 W average draw

Rated 12 W, drawing that for 100% of the 24 hours a day it is in service, 365 days a year.

12 W while running never cycles — the plate is right for once

Run the numbers on your own use

Change any of these and the figures update. The defaults are the typical case described above; your rate is the input that moves the answer most.

Residential average for June 2026, from the EIA. Your own tariff may differ; you can read it off your bill.

12 W
100%
24 h/day
365 days/yr
A year
$19
A month
$1.61
Electricity
105 kWh
Average draw
12 W

In the US average at 18.34¢ per kWh. Nameplate arithmetic would say 105 kWh too high.

Why this is lower than the number you will see elsewhere

Almost every published answer to this question multiplies the rating on the label by the hours the appliance is switched on. For a wi-fi router and modem that gives 105 kWh a year, or $19.

There is no off state in normal use.

Nameplate × hours — the usual answer105 kWh$19
What it actually draws105 kWh$19

The arithmetic, step by step

Nothing here is hidden, so you can check it or change it. Working in the order the formula runs:

  1. 12 W — what it draws while it is actually drawing. This is the rating on the plate.
  2. × 100% — the share of its in-service time it is really pulling that. There is no off state in normal use.
    That gives 12 W averaged across the hours it is on.
  3. × 24 hours a day × 365 days — Router plus modem, running continuously.
    12 × 24 × 365 ÷ 1,000 = 105 kWh a year.
  4. × 18.34¢ — the US average residential rate for June 2026.
    105 kWh × 18.34¢ = $19 a year.

Change any assumption in the calculator above and every figure on this page moves with it. The two that matter most are your rate, which varies 4× across the country, and the hours — the duty cycle is a property of the appliance, but the hours are a property of you.

How sensitive is that number?

A single figure invites more confidence than it deserves. Here is the same appliance under assumptions either side of the default, so you can see how much of the answer is the appliance and how much is the guess about how you use it.

Everything else held at the default. The spread here is the honest error bar on the headline figure.

If…ElectricityA yearvs default
You use it half as much (12.00 h/day)105 kWh$19+0%
You use it 50% more (36.00 h/day)105 kWh$19+0%
It is a smaller unit (5 W)44 kWh$8.03-58%
It is a larger unit (25 W)219 kWh$40+108%
You are in Nevada (13.11¢)105 kWh$14-29%
You are in Hawaii (52.72¢)105 kWh$55+187%

What it costs per hour, day and month

At 18.34¢ per kWh, the US residential average for June 2026.

PeriodElectricityCost
Per hour in use0 kWh0.2¢
Per day in use0.3 kWh$0.05
Per month8.8 kWh$1.61
Per year105 kWh$19
Over ten years1,051 kWh$193

The thing worth knowing

Small draw, but 8,760 hours a year. This is the shape of most of the ‘other' slice on a bill: nothing individually worth switching off, and a meaningful total once you count how many of them there are.

What it costs in your state

The appliance is the same everywhere; the rate is not. Running this wi-fi router and modem costs $55 a year in Hawaii and $14 in Nevada — a difference of 4×.

Cost of running one wi-fi router and modem for a year, by state. Residential average price, EIA June 2026.

StateRatePer yearPer month
Hawaii52.72¢$55$4.62
California34.74¢$37$3.04
Massachusetts29.61¢$31$2.59
Maine29.59¢$31$2.59
New York29.49¢$31$2.58
Rhode Island29.23¢$31$2.56
Alaska28.21¢$30$2.47
New Hampshire27.01¢$28$2.37
New Jersey24.95¢$26$2.19
Vermont24.44¢$26$2.14
District of Columbia24.39¢$26$2.14
Connecticut24.32¢$26$2.13
Michigan22.99¢$24$2.01
Maryland21.84¢$23$1.91
Pennsylvania21.73¢$23$1.90
Illinois19.89¢$21$1.74
Wisconsin19.56¢$21$1.71
Delaware19.29¢$20$1.69
Ohio19.19¢$20$1.68
Minnesota17.52¢$18$1.53
Indiana17.51¢$18$1.53
Virginia17.22¢$18$1.51
Colorado17.13¢$18$1.50
Alabama16.4¢$17$1.44
Georgia16.36¢$17$1.43
Oregon16.32¢$17$1.43
Missouri16.22¢$17$1.42
Texas15.94¢$17$1.40
Iowa15.93¢$17$1.40
Kansas15.71¢$17$1.38
South Carolina15.55¢$16$1.36
West Virginia15.45¢$16$1.35
South Dakota15.36¢$16$1.35
Wyoming15.24¢$16$1.34
Arizona15.18¢$16$1.33
Montana15.14¢$16$1.33
Florida15.1¢$16$1.32
New Mexico15.06¢$16$1.32
Washington14.91¢$16$1.31
Mississippi14.88¢$16$1.30
North Carolina14.74¢$15$1.29
Idaho14.37¢$15$1.26
Oklahoma14.33¢$15$1.26
Kentucky14.26¢$15$1.25
Arkansas14.12¢$15$1.24
North Dakota14.12¢$15$1.24
Tennessee14.07¢$15$1.23
Louisiana13.49¢$14$1.18
Utah13.37¢$14$1.17
Nebraska13.25¢$14$1.16
Nevada13.11¢$14$1.15

Questions

How much electricity does a wi-fi router and modem use?
About 105 kWh a year on the assumptions above — router plus modem, running continuously. That works out to an average draw of 12 W over the hours it is in service, against a rated 12 W.
Is it expensive to run a wi-fi router and modem?
At the US average residential rate of 18.34¢ per kWh it costs about $19 a year, or $1.61 a month. The same appliance costs about $14 a year in Nevada and $55 in Hawaii, because the rate matters more than the appliance.
Why is your figure lower than other sites?
Because 12 W is what the appliance draws while it is actually drawing, not the average over the time it is switched on. There is no off state in normal use. Multiplying the rating by the hours gives 105 kWh a year, which is 1× the real figure.
What is the cheapest way to run a wi-fi router and modem?
Not much to do here, and switching it off nightly saves pennies. This entry exists to be counted, not cut.

Source: U.S. Energy Information Administration, Electric Power Monthly, Table 5.6.A, June 2026. U.S. Government work, public domain.

How every figure on this page is computed · Where the data comes from