CostToRunIt

Water Heating

Electric Water Heater running cost, by state

A electric water heater drawing 4000W costs about $363 a year at the US average electricity rate — but that average hides a fourfold spread. Pick your state for a real figure.

At the US average rate

Per hour$0.3321.800 kWh
Per day$1.005.40 kWh
Per month$30.31164.4 kWh
Per year$3631,971 kWh

4000W at a 45% duty cycle, 3 hours a day, at 18.44¢/kWh.

About this appliance

Typically the second-largest load in a home after heating and cooling. Tank models reheat continuously to counter standby loss; heat pump water heaters cut consumption by roughly two-thirds.

  • Nameplate wattage is not running cost. This electric water heater draws about 4000W when active, but cycles roughly 45% of the time it is switched on, so effective consumption is near 1800W.
  • At typical use this is a major load - around 1,971 kWh a year. Efficiency upgrades here pay back faster than on any small appliance.
  • If your utility offers time-of-use pricing, shifting this load off-peak can cut its cost substantially without using any less energy.

Annual cost in every state

Sorted cheapest first. Click any state for the full calculation with that state’s rate loaded.

Electric Water Heater: annual running cost by state
StateRate /kWh Per monthPer yearRelative
Idaho 12.35¢ $20.30 $243
Utah 12.96¢ $21.30 $255
Oklahoma 13.38¢ $21.99 $264
Nebraska 13.59¢ $22.34 $268
Nevada 13.60¢ $22.36 $268
North Dakota 13.61¢ $22.37 $268
Missouri 13.68¢ $22.49 $270
New Mexico 14.12¢ $23.21 $278
Iowa 14.14¢ $23.24 $279
Louisiana 14.15¢ $23.26 $279
Arkansas 14.36¢ $23.60 $283
Tennessee 14.47¢ $23.79 $285
Montana 14.67¢ $24.11 $289
Wyoming 14.80¢ $24.33 $292
Washington 14.95¢ $24.57 $295
Kentucky 14.98¢ $24.62 $295
North Carolina 15.09¢ $24.80 $297
Kansas 15.13¢ $24.87 $298
Florida 15.17¢ $24.94 $299
Arizona 15.23¢ $25.03 $300
South Dakota 15.73¢ $25.86 $310
Georgia 15.84¢ $26.04 $312
Colorado 16.16¢ $26.56 $319
Mississippi 16.16¢ $26.56 $319
South Carolina 16.18¢ $26.60 $319
Oregon 16.27¢ $26.74 $321
Texas 16.44¢ $27.02 $324
Alabama 16.77¢ $27.57 $331
West Virginia 16.80¢ $27.62 $331
Minnesota 16.95¢ $27.86 $334
Virginia 17.61¢ $28.95 $347
Indiana 18.15¢ $29.83 $358
Delaware 19.38¢ $31.86 $382
Ohio 19.52¢ $32.09 $385
Wisconsin 19.74¢ $32.45 $389
Pennsylvania 21.55¢ $35.42 $425
Maryland 21.77¢ $35.78 $429
Michigan 22.01¢ $36.18 $434
New Jersey 23.27¢ $38.25 $459
Illinois 23.85¢ $39.20 $470
Vermont 24.89¢ $40.91 $491
District of Columbia 25.40¢ $41.75 $501
New Hampshire 27.33¢ $44.92 $539
Connecticut 27.37¢ $44.99 $539
Alaska 28.23¢ $46.40 $556
Maine 28.63¢ $47.06 $564
Massachusetts 28.82¢ $47.37 $568
Rhode Island 29.46¢ $48.43 $581
New York 29.93¢ $49.20 $590
California 33.25¢ $54.66 $655
Hawaii 52.00¢ $85.48 $1,025

Common questions

How many watts does a electric water heater use?

A typical electric water heater draws about 4000 watts while running, with most models falling between 3000W and 5500W. Check the nameplate label or manual for your specific unit - the range is wide enough that averages can mislead.

How much electricity does a electric water heater use per day?

At around 3 hours of use a day and a 45% duty cycle, that works out to roughly 5.4 kWh per day, or about 162 kWh a month. Your actual figure depends on your usage and model.

Why does the cost differ so much between states?

Residential electricity rates across the US range from about 12.35 cents per kWh in North Dakota to 46.62 cents in Hawaii - nearly a fourfold difference. The same electric water heater, used identically, therefore costs almost four times as much to run in the most expensive state as in the cheapest.

Is it cheaper to run a electric water heater at night?

Only if you are on a time-of-use or variable tariff. On a flat rate, the time of day makes no difference to cost. If you are on time-of-use pricing, off-peak hours are typically materially cheaper, and shifting this load can reduce its cost without reducing usage.

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