Billowatt

Cost to Run a Tankless Electric Water Heater in Hawaii

Hawaii's average residential electricity rate is 46.6¢/kWh as of April 2026 — the 51st cheapest in the country, 148% above the U.S. average. At typical usage (0.7 hours/day), a tankless electric water heater here costs $178 per month.

Per hour

$8.39

at 13,000–27,000 W

Per day

$5.87

0.7 hours/day

Per month

$178

383 kWh

Per year

$2,143

4,599 kWh

By usage level in Hawaii

Usage Per day Per month Per year
Light (0.5 hrs/day) $2.94 $89.25 $1,072
Typical (0.7 hrs/day) $5.87 $178 $2,143
Heavy (1.4 hrs/day) $11.74 $357 $4,286

Hawaii vs. the rest of the country

Monthly cost at typical usage.

Hawaii $178
West average $75.31
U.S. average $72.01

Frequently asked questions

How much does it cost to run a tankless electric water heater in Hawaii?

At Hawaii's current average residential rate of 46.6¢/kWh (April 2026), a tankless electric water heater with typical usage costs about $5.87 per day, $178 per month, or $2,143 per year.

Is running a tankless electric water heater in Hawaii more expensive than average?

Yes. Hawaii's electricity costs about 148% more than the U.S. average, so the same usage costs $178 per month here versus $72.01 nationally.

What does electricity cost in Hawaii right now?

Hawaii residents pay an average of 46.6¢ per kWh as of April 2026 — the 51st cheapest rate of the 51 U.S. jurisdictions we track.

Tankless Electric Water Heater costs in nearby states

What else costs to run in Hawaii

See the full Hawaii electricity cost guide →