How much does an electric water heater cost to run in Hawaii?
$241 a month
- A day of use
- $7.91
- An hour of running
- $2.64
- A year
- $2,886.42
5,000 W, 3 hours a day of element heating time (tank type), at Hawaii’s average rate of 52.7¢ per kWh (EIA, June 2026). How we calculate this
Change the watts, hours or rate
What it costs at other usage levels
| Use | A day | A month | A year |
|---|---|---|---|
| 1 hour a day | $2.64 | $80.18 | $962.14 |
| 2 hours a day | $5.27 | $160.36 | $1,924.28 |
| 3 hours a day typical | $7.91 | $240.54 | $2,886.42 |
| 4 hours a day | $10.54 | $320.71 | $3,848.56 |
| 8 hours a day | $21.09 | $641.43 | $7,697.12 |
| 24 hours a day | $63.26 | $1,924.28 | $23,091.36 |
Models range from 4,500 W to 5,500 W (Virginia Cooperative Extension). We use 5,000 W, the middle of that range.
Hawaii compared with other states
Hawaii’s residential rate is the 1st most expensive of 51 states and DC, 34.4¢ above the US average of 18.3¢ (+187%). Hawaii’s rate is up 11.8¢ from June 2025 (41.0¢, +28.7%).
Ways to spend less
- Turn the tank thermostat down to the lowest setting that still gives comfortable showers.
- Fix dripping hot taps and fit low-flow shower heads.
- Wash clothes in cold water.
- Cut heating time by an hour a day with shorter showers. Saves about $80.18 a month.
Questions
How much does it cost to run an electric water heater per hour?
About $2.64 an hour in Hawaii. An electric water heater at 5,000 W uses 5.00 kWh per hour, and at Hawaii’s average of 52.7¢ per kWh that comes to $2.64.
How much does an electric water heater add to your electric bill?
Used 3 hours a day of element heating time (tank type), about $240.54 a month in Hawaii, or $2,886.42 a year.
How much does it cost to run an electric water heater 24 hours a day?
Running nonstop, an electric water heater would use 120 kWh a day and cost $63.26 a day, or $1,924.28 over an average month in Hawaii.
How many watts does an electric water heater use?
Models range from 4,500 W to 5,500 W (Virginia Cooperative Extension). We use 5,000 W, the middle of that range. Check the label on yours: cost scales directly with watts, so a 20% lower wattage means a 20% lower bill.
Why does an electric water heater cost more or less to run in Hawaii than elsewhere?
Hawaii’s residential rate is the 1st most expensive of 51 states and DC, 34.4¢ above the US average of 18.3¢ (+187%). Hawaii’s rate is up 11.8¢ from June 2025 (41.0¢, +28.7%). The appliance uses the same energy everywhere; only the price per kWh changes.
Sources
- Virginia Cooperative Extension: Estimating appliance and home electronic energy use (reproduces U.S. Department of Energy sample wattages)
- Penn State EGEE 102: Typical range of power consumption (wattage)
- U.S. Energy Information Administration, Electric Power Monthly, Table 5.6.A: average price of electricity to ultimate customers, residential, June 2026 Figures transcribed from republications of this table on September 26, 2026; pending direct verification from the EIA API.
- Carrier page: June 2026 residential average price, citing EIA Electric Power Monthly Table 5.6.A
Usage assumptions (hours a day, season) are ours and listed on the methodology page. Found an error? Tell us.