How Much Does a Tankless Water Heater Cost to Run?

A tankless water heater costs approximately $701/year to run at $0.16/kWh. That is $58.40/month or $3.840/hour.

💰 Tankless Water Heater Running Cost Calculator

$0.16/kWh
0.5 hrs
365
Per Hour
$3.840
Per Day
$1.92
Per Month
$58.40
Per Year
$701
5-Year Cost
$3,504
kWh/Year
4,380

Based on 24000W rated power. Actual varies by model and usage.

Tankless Water Heater Cost at Different Rates

RateMonthlyAnnual
$0.08$29.17$350
$0.10$36.50$438
$0.12$43.83$526
$0.16$58.42$701
$0.20$73.00$876
$0.25$91.25$1,095
$0.30$109.50$1,314
$0.35$127.75$1,533

Tankless Water Heater Energy Usage Explained

A tankless water heater consumes 24000W. At 0.5 hours/day for 365 days/year, that is 4,380 kWh annually — about 41.7% of average US household usage (10,500 kWh).

How to Calculate Running Cost

Cost = (Watts ÷ 1000) × Hours × Rate

For your tankless water heater: (24000W ÷ 1000) × 0.5 hrs × $0.16/kWh = $1.92/day.

Tips to Reduce Costs

Use time-of-use electricity plans for off-peak rates ($0.05–$0.10/kWh overnight). Upgrade to Energy Star certified models. Use smart plugs or timers. Check rates in your state with our Electricity Cost Calculator.

Disclaimer: Estimates based on rated wattage. Actual consumption varies by model, age, and usage patterns.

Frequently Asked Questions