Watt Does It Cost
RESIDENTIAL · kWh

How much does it cost to run an electric water heater?

An electric water heater drawing 4,000 watts, used 3 hours a day, uses about 12.00 kWh per day and costs about $2.33 per day, $70.90 per month, and $850.16 per year at the US average residential rate of 19.4¢/kWh. Enter your own wattage, hours, and state below for an exact figure.

Check the label or power brick
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Per day
Per month
30.44-day month
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FORMULA  watts × hours ÷ 1,000 × rate  ·  updates as you type

Estimates only — based on typical wattages and average state rates, not your actual bill.

What drives the cost

A tank water heater's elements draw 3,000-5,500 watts, but they only energize when the tank needs reheating — typically three to five hours of total element time per day for a family. Standby loss (heat escaping the tank) means it costs something even on days you barely use hot water. Water heating is commonly the second-largest electricity use in an all-electric home.

Cost at different daily usage

Same electric water heater at 4,000 watts, run for different amounts of time, at 19.4¢/kWh.

Highlighted row is the typical usage assumed elsewhere on this page.
UsagekWh/dayPer day Per monthPer year
1.5 h/day6.00 kWh$1.16$35.45$425.08
3 h/day12.00 kWh$2.33$70.90$850.16
4.5 h/day18.00 kWh$3.49$106.35$1,275.24
6 h/day24.00 kWh$4.66$141.80$1,700.32

Cost by model power draw

Not all models are equal. At 3 h/day, here is what the range costs.

Wattage ranges are typical for this appliance class; check your unit's label.
ModelPowerkWh/day Per dayPer month
Low-draw model3,000 W9.00 kWh$1.75$53.18
Typical4,000 W12.00 kWh$2.33$70.90
High-draw model5,500 W16.50 kWh$3.20$97.49

Cost by state

An electric water heater at 4,000 W for 3 h/day, priced at each state's average residential rate.

Residential electricity rates for May 2026 from the US Energy Information Administration (Open Data API, electricity/retail-sales, residential sector — the dataset published as Electric Power Monthly Table 5.6.A). Recent months are preliminary EIA estimates and may be revised. Retrieved 2026-08-12.
StateRatePer day Per monthPer year
Alabama16.8¢$2.01$61.26$734.53
Alaska28.2¢$3.39$103.12$1,236.47
Arizona15.2¢$1.83$55.63$667.07
Arkansas14.4¢$1.72$52.45$628.97
California33.2¢$3.99$121.46$1,456.35
Colorado16.2¢$1.94$59.03$707.81
Connecticut27.4¢$3.28$99.98$1,198.81
Delaware19.4¢$2.33$70.79$848.84
District of Columbia25.4¢$3.05$92.78$1,112.52
Florida15.2¢$1.82$55.41$664.45
Georgia15.8¢$1.90$57.86$693.79
Hawaii52.0¢$6.24$189.95$2,277.60
Idaho12.3¢$1.48$45.11$540.93
Illinois23.9¢$2.86$87.12$1,044.63
Indiana18.1¢$2.18$66.30$794.97
Iowa14.1¢$1.70$51.65$619.33
Kansas15.1¢$1.82$55.27$662.69
Kentucky15.0¢$1.80$54.72$656.12
Louisiana14.2¢$1.70$51.69$619.77
Maine28.6¢$3.44$104.58$1,253.99
Maryland21.8¢$2.61$79.52$953.53
Massachusetts28.8¢$3.46$105.27$1,262.32
Michigan22.0¢$2.64$80.40$964.04
Minnesota16.9¢$2.03$61.91$742.41
Mississippi16.2¢$1.94$59.03$707.81
Missouri13.7¢$1.64$49.97$599.18
Montana14.7¢$1.76$53.59$642.55
Nebraska13.6¢$1.63$49.64$595.24
Nevada13.6¢$1.63$49.68$595.68
New Hampshire27.3¢$3.28$99.83$1,197.05
New Jersey23.3¢$2.79$85.00$1,019.23
New Mexico14.1¢$1.69$51.58$618.46
New York29.9¢$3.59$109.33$1,310.93
North Carolina15.1¢$1.81$55.12$660.94
North Dakota13.6¢$1.63$49.71$596.12
Ohio19.5¢$2.34$71.30$854.98
Oklahoma13.4¢$1.61$48.87$586.04
Oregon16.3¢$1.95$59.43$712.63
Pennsylvania21.6¢$2.59$78.72$943.89
Rhode Island29.5¢$3.54$107.61$1,290.35
South Carolina16.2¢$1.94$59.10$708.68
South Dakota15.7¢$1.89$57.46$688.97
Tennessee14.5¢$1.74$52.86$633.79
Texas16.4¢$1.97$60.05$720.07
Utah13.0¢$1.56$47.34$567.65
Vermont24.9¢$2.99$90.92$1,090.18
Virginia17.6¢$2.11$64.33$771.32
Washington14.9¢$1.79$54.61$654.81
West Virginia16.8¢$2.02$61.37$735.84
Wisconsin19.7¢$2.37$72.11$864.61
Wyoming14.8¢$1.78$54.06$648.24

How to cut the cost

Compare with related appliances

Monthly cost at typical usage and 19.4¢/kWh.

Questions

How many hours a day does a water heater actually run?

The elements typically energize for roughly three to five hours total per day in a household of two to four people, spread across many short cycles rather than one continuous run.

Is a tankless water heater cheaper to run?

Tankless units eliminate standby loss and can lower running cost, but they draw far more power while active and often require electrical upgrades. Savings depend heavily on usage pattern and local rates.

How do you calculate what an electric water heater costs to run?

Multiply its wattage by the hours it runs per day, divide by 1,000 to get kilowatt-hours, then multiply by your electricity rate. For an electric water heater: 4,000 W × 3 h ÷ 1,000 = 12.00 kWh per day, which at 19.4¢/kWh is $2.33 per day.

How many watts does an electric water heater use?

Typically 4,000 watts, with most models falling between 3,000 and 5,500 watts. The label on the appliance or its power supply gives the figure for your specific unit.