How much does an electric water heater cost per month in Hawaii?

About $138 a month, assuming 3,500 kWh a year at 47.18¢/kWh.

How many kilowatt-hours does an electric water heater use?

Roughly 3,500 kWh a year under these assumptions.

Is that expensive compared with other states?

Hawaii has the most expensive average residential rate in the country, so this appliance costs more here than the U.S. average of $636 a year.

Home › Electric water heater › Hawaii

Cost to run an electric water heater in Hawaii (August 2026 rates)

At 47.18¢ per kilowatt-hour — Hawaii's average residential price in August 2026 — running an electric water heater costs $1,651 a year. That is 160% more than the national average of $636. Hawaii's residential rate is up 22.5% from August 2025, which moves this appliance from $1,349 to $1,651 a year.

Per day: $4.52
Per month: $138
Per year: $1,651

Assumption: 3,500 kWh a year. A 50-gallon resistance tank for a household of three or four. This is typically the largest or second-largest electric load in a home without electric heat. Use the calculator to swap in the numbers from your own model.

Related calculators: work out whether a heat-pump water heater pays back.

How Hawaii compares

Hawaii pays 47.18¢/kWh, the most expensive residential electricity of the 51 U.S. jurisdictions EIA reports. For this appliance that works out to $1,016 more a year than the typical U.S. household pays for the same use. Running the same electric water heater costs $445 a year in Nevada and $1,651 in Hawaii, so where you live changes this bill by $1,206 a year.

State	Rate	Per month	Per year
Alaska	29.41¢	$85.78	$1,029
California	29.75¢	$86.77	$1,041
Massachusetts	30.48¢	$88.90	$1,067
Maine	32.11¢	$93.65	$1,124
Hawaii	47.18¢	$138	$1,651

States ranked by average residential price, cheapest first. See all 51 states for an electric water heater.

What else costs about the same in Hawaii

Electric car$1,793 a year in HI Hot tub$1,180 a year in HI Central air conditioner$1,110 a year in HI

Cutting the number down

A heat-pump water heater does the same job for roughly a third of the electricity, which is why it usually pays back faster than any other upgrade in the house.
Dropping the setpoint from 140 F to 120 F cuts standby losses and scalding risk at once.
An insulating blanket on an older tank pays for itself in a season; check the manufacturer's guidance first.

Questions

How much does an electric water heater cost per month in Hawaii?: About $138 a month, assuming 3,500 kWh a year at 47.18¢/kWh.
How many kilowatt-hours does an electric water heater use?: Roughly 3,500 kWh a year under these assumptions.
Is that expensive compared with other states?: Hawaii has the most expensive average residential rate in the country, so this appliance costs more here than the U.S. average of $636 a year.